CN114607392B - Sand and gravel stratum classification method based on shield engineering characteristics - Google Patents
Sand and gravel stratum classification method based on shield engineering characteristics Download PDFInfo
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Classifications
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D9/00—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries
- E21D9/003—Arrangement of measuring or indicating devices for use during driving of tunnels, e.g. for guiding machines
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D9/00—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries
- E21D9/06—Making by using a driving shield, i.e. advanced by pushing means bearing against the already placed lining
- E21D9/0642—Making by using a driving shield, i.e. advanced by pushing means bearing against the already placed lining the shield having means for additional processing at the front end
- E21D9/0678—Adding additives, e.g. chemical compositions, to the slurry or the cuttings
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D9/00—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries
- E21D9/06—Making by using a driving shield, i.e. advanced by pushing means bearing against the already placed lining
- E21D9/08—Making by using a driving shield, i.e. advanced by pushing means bearing against the already placed lining with additional boring or cutting means other than the conventional cutting edge of the shield
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D9/00—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries
- E21D9/12—Devices for removing or hauling away excavated material or spoil; Working or loading platforms
- E21D9/124—Helical conveying means therefor
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F18/00—Pattern recognition
- G06F18/20—Analysing
- G06F18/24—Classification techniques
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Abstract
The invention discloses a sandy gravel stratum classification method based on shield engineering characteristics, which comprises the following steps: determining main influence factors of the shield tunneling of the sandy cobble stratum; determining characteristic indexes of all influence factors; classifying the sandy gravel stratum under each influence factor according to the index characteristic value, and matching tunneling technical measures according to classification; and acquiring the shield engineering characteristics of the sandy gravel stratum in the shield tunnel, and providing a corresponding technical scheme according to the determined classification and technical measures. The invention provides qualitative classification description and quantitative classification indexes, overcomes the defect that classification is carried out only by depending on geological factors, engineering experience or a small amount of single indexes in the existing sandy cobble classification, perfects a shield construction technical system under the sandy cobble stratum condition, improves the pertinence and scientificity of shield equipment selection and shield tunneling technical scheme selection, and has guiding significance for the design and construction of a sandy cobble stratum shield tunnel.
Description
Technical Field
The invention relates to the technical field of shield construction, in particular to a sandy cobble stratum in construction, and specifically relates to a sandy cobble stratum classification method based on shield engineering characteristics.
Background
The shield construction is widely applied to the construction of various large-city projects by virtue of the advantages of safety, reliability, rapidness, economy, environmental protection and the like, and becomes a municipal rail transit construction method commonly used at home and abroad. The shield construction is greatly influenced by stratum conditions, and the standardization of the shield construction are restricted by variable environmental conditions and hydrogeological conditions. The sandy cobble stratum is used as a representative geological environment, the special geological problem of the stratum is complex, and the determination of the proper shield construction classification standard or control range according to the sandy cobble geological characteristics is extremely difficult, so that a uniform classification method cannot be established for shield tunneling of the stratum. The prior art for dividing the information of the shield tunnel stratum mainly comprises the steps of classifying by adopting geological prospecting methods such as field drilling and in-situ testing, classifying according to shield related standard specifications, classifying according to engineering experience and classifying according to the single characteristic of a sandy gravel stratum.
The method adopts geological survey methods such as field drilling, in-situ testing and the like for classification, can only roughly obtain the stratum type of a tunnel construction area, and carries out qualitative geological classification of geography, and the classification method has no great guiding significance in complex sandy gravel shield construction.
The classification according to the relevant shield standard specification can provide the basic basis of shield construction, but the classification still cannot be widely applied to sandy gravel strata. For example, in the specification of railway tunnel design, sandy gravel soil is only classified into soil simply, engineering geological characteristics of the soil-rock mixture are not considered, and only qualitative analysis is given, such as water content division, and only water-rich sandy gravel stratum and water-free sandy gravel stratum are qualitatively classified at present.
The method is characterized by classifying according to engineering experience, establishing on the basis of a large amount of engineering experience, classifying the shield characteristics of the sandy gravel stratum according to the regional characteristics, being greatly limited by geographical regions, lacking specific methods and indexes and having hysteresis for designers.
The sand and pebble stratum is classified according to the single characteristics of the sand and pebble stratum, and the prior Chinese patent application CN2021113244555 discloses a muck improvement method based on cobble stratum shield engineering characteristic classification, which divides the sand and pebble characteristic particle size. The prior Chinese patent application CN202110167595X discloses a sandy cobble stratum shield tunnel geological evaluation method, which divides the degree of sandy cobble abrasion. The methods all focus on a certain aspect or a certain index, are not systematic and comprehensive, cannot consider the complex geological characteristics of the sandy gravel stratum, cannot be effectively applied, and cannot ensure the smooth tunneling of the shield.
In conclusion, the existing sand-gravel stratum classification methods have the defects of incompleteness, no system and incapability of effectively guiding shield construction. No unified and mature technical system exists for representing the shield characteristics of the sandy gravel stratum by adopting which indexes and how to obtain the index characteristic values to define the influence degree of the indexes on the shield construction.
Therefore, a new sand and gravel stratum classification and construction method based on shield engineering characteristics, which is beneficial to normalized and standardized construction, needs to be provided.
Disclosure of Invention
In view of the defects of the prior art, the main object of the present invention is to provide a sand and gravel stratum classification method based on shield engineering characteristics, so as to solve one or more problems in the prior art.
The invention is realized by the following steps:
a sand and gravel stratum classification method based on shield engineering characteristics comprises the following steps:
the method comprises the following steps: based on the sandy cobble stratum shield construction engineering characteristics, potential technical factors of stratum conditions influencing shield tunneling are analyzed, and four main technical factors influencing sandy cobble stratum shield tunneling are obtained: the factors of particle size of broken before a cutter head, fine particle content of improved muck by adding a modifying agent, water pressure of gushing of a screw conveyor and abrasion degree of severe abrasion of the cutter are required;
step two: determining characteristic indexes of each technical factor;
step three: classifying the sandy gravel stratum according to different shield tunneling technical schemes to be caused by various characteristic indexes, and matching tunneling technical measures according to stratum classification;
step four: and (4) acquiring the shield engineering characteristics of the sandy gravel stratum of the shield tunnel, and providing a corresponding construction scheme according to the classification standard and the tunneling technical measures determined in the step three.
Preferably, in step two:
characteristic indicators of particle size include: maximum particle size of pebblesd max Maximum passing capacity of screw conveyerd p ；
The determination method comprises the following steps: maximum particle size of pebblesd max Obtaining through a survey report; maximum throughput capacity of screw conveyord p Calculated by the form of the screw conveyer and the size of the conveying opening and depends on the inner diameter of the conveying cylinder of the screw conveyerD 1 Outer diameter of screw conveyor shaftD 2 、D 3 Single sided loop bandwidth therebetweend x And net pitchl x Of shaft and belt screw conveyorsd x 、l x The following equation (1) and equation (2) respectively determine:
In the formula (I), the compound is shown in the specification,D 2 、D 3 respectively are the shaft outer diameter of a shaft type screw conveyer and the shaft outer diameter of a belt type screw conveyer,pthe pitch of the helical blades is set as follows,tis the thickness of the helical bladed x /l x ≥1Maximum throughput of screw conveyord p =d x (ii) a When in used x /l x ＜1Maximum throughput of screw conveyord p =l x 。
Preferably, in step two:
the characteristic indicators of the fine particle content include: mass ratio of fine particles with particle size less than 75um in stratumd 75 ；
The determination method comprises the following steps: sampling in a shield interval, carrying out a particle size analysis test, and calculating the percentage of the mass of fine particles with the particle size of less than 75um in the sample to the total mass of the sample by the formula (3):
In the formula:
-mass of fines (g) with a particle size of less than 75 um;m d -total mass (g) of samples taken while carrying out the sieve analysis test.
Preferably, in step two:
the characteristic indexes of the water pressure include: height of underground water levelh w Limit water level heighth 0 ；
The determination method comprises the following steps: the horizontal line at the elevation of the soil bin bottom of the shield tunneling machine is establishedxThe shaft is provided with a plurality of axial holes,xthe intersection point of the shaft and the excavation surface in the soil bin is an original point, a position water head at the original point is set to be 0 through a coordinate system taking an original point plumb line as a y axis, and the height of the underground water level is set to be 0h w Setting the height of water level at the position 1m above the rear gate of the screw conveyor as a limith 0 。
Preferably, in step two:
the characteristic indicators of the degree of abrasion include: average content of quartzQ S ；
The determination method comprises the following steps: according to shield interval geological exploration data, obtaining interval stratum quartz average content, and according to data point fitting, obtaining quartz average contentQ S And abrasion valueA C The linear regression relationship of (1):
Preferably, in step three:
according to maximum particle size of pebblesd max Maximum capacity of screw conveyerd p The relationship of (a) divides the sandy gravel stratum into two types:
the first type:d max ≥d p the method comprises the following steps of (1) adopting a wedge beating-conveying-discharging tunneling mode according to the principle of 'breaking to the greatest extent, breaking large blocks and conveying and discharging integrally';
the second type:d max ＜d p and the sand-gravel stratum can be transported and discharged without being crushed: the principle of 'wedge plough-loosening-stripping excavation and integral conveying and discharging' is followed, and a 'wedge plough-conveying and discharging' tunneling mode is adopted.
Preferably, in step three:
according to the mass ratio of fine particles with the particle diameter of less than 75umd 75 The sandy gravel stratum is divided into two types:
the first type:d 75 ≥30%a low permeability sandy-pebble formation of high viscous particle content;
the foaming agent and water are used as main improvement materials, so that the flowability of the muck is increased, the adhesion is reduced, and the muck is prevented from being bonded on a cutter head and the wall of a soil bin to form a mud cake;
the second type:d 75 ＜30%a highly permeable sandy gravel formation of low viscous particle content;
the bentonite or clay mineral mud and the foaming agent are used as main improvement materials to supplement the content of fine particles, improve the fluidity and improve the water stopping property.
Preferably, in step three:
in a highly permeable sandy gravel stratum, according to the height of underground water levelh w Limit water level heighth 0 The characteristic underground water occurrence condition is that the sandy cobble stratum is secondarily subdivided into two types:
the first type:h w ≥h 0 high hydraulic pressure sand gravel formation;
the high water-absorbing resin and the foaming agent are used as main improvement materials, the high water-absorbing resin can reduce the gaps among particles, so that a soil body is changed into a gel state, the cohesiveness and the water-stopping property of dregs are improved, and the shield spiral conveyor in a high-water-pressure stratum is prevented from gushing;
the second type:h w ＜h 0 low water pressure sand gravel formation;
the bentonite slurry and the foaming agent are used as main improvement materials, the plastic fluidity and the cohesiveness of the slag soil are increased, the frictional resistance is reduced, and the cutter head torque is reduced.
Preferably, in the third step:
according to the average quartz contentQ S Sand and gravel strata are divided into two categories:
the first type is:Q S ≥80%(ii) a A highly abrasive sandy gravel formation;
the cutter is configured in a multi-layer echelonment manner, so that the abrasion resistance of the cutter head and the cutter is improved; the opening rate of the cutter head and the grain diameter of the spiral conveyor which can convey and discharge are increased, the complete discharge is realized, and the 'discharge stagnation' phenomenon of pebble grains in the front of the cutter head, the soil bin and the spiral conveyor is reduced; the erosion-resistant abrasion-reducing wear control method and the high-penetration low-rotation tunneling mode are adopted, so that the impact damage of the cutter is reduced, and the conventional abrasion coefficient of the cutter is reduced; the foaming agent and the bentonite slurry are used as main improvement materials to wrap and lubricate the sand and pebble particles, so that the internal friction angle is reduced, and the cutter abrasion is reduced;
the second type:Q S ＜80%(ii) a A weakly abrasive sandy gravel formation;
the shield tunneling machine has the advantages that the shield tunneling machine improves the shield tunneling propulsion speed and the cutter head rotating speed, properly reduces the cutter layering and the cutter arrangement quantity, reduces the cutter head torque and improves the tunneling efficiency.
Preferably, the fourth step includes:
(1) distributing stratum codes to four main technical factors, wherein the 1 st digit represents the content of fine particles, the 2 nd digit represents the water pressure, the 3 rd digit represents the abrasion degree, the 4 th digit represents the particle size, and each digit is divided into 1 and 2 grades according to the degree from weak to strong;
(2) acquiring the shield engineering characteristics of the sandy cobble stratum of the shield tunnel, establishing the corresponding relation between the shield engineering characteristics and stratum codes, and acquiring the stratum codes consisting of 4-bit character codes;
(3) and (4) providing a corresponding technical scheme according to the stratum classification standard and the tunneling technical measure determined in the third step and by combining stratum coding.
Compared with the prior art, the invention has the beneficial effects that: by adopting the sandy gravel stratum classification method, a sandy gravel stratum shield construction evaluation system can be perfected, qualitative classification description and quantitative grading indexes are provided, and the defect that classification is carried out only by depending on geological exploration, engineering experience or a small amount of single indexes in the prior art is overcome. The proposed classification method has guiding significance for the construction and design of the sandy gravel stratum shield tunnel. Specifically, at least the following practical effects are obtained:
(1) the method determines four main influence factors of the sand and pebble stratum characteristics on shield tunneling, including particle size, fine particle content, water pressure and abrasion degree, provides a determination method for each characteristic index, determines a characteristic value range of each index, defines the stratum type of a shield interval according to the characteristic value range, and further matches with an appropriate construction scheme. The method has the advantages that the shield construction measures of the sandy gravel tunnel are more targeted, a series of construction problems encountered in the sandy gravel stratum are effectively guided and solved, the standardized construction under the sandy gravel geological condition is further promoted, and a scientific basis is provided for the long-distance efficient tunneling of the sandy gravel stratum.
(2) The evaluation index selection of the method is scientific and accurate, the evaluation method is simple and practical, the method is suitable for shield constructors to perform on-site real-time evaluation according to geological exploration data, qualitative and quantitative basis can be provided for the particle size, the fine particle content, the water pressure and the abrasion degree, the defect that classification is performed only by depending on geological exploration, engineering experience or a small amount of single index in the existing evaluation technology is overcome, the scientificity and the accuracy of the classification method are improved, and the progress of the sandy gravel stratum shield technology can be promoted.
(3) The geological characteristics of the sandy gravel stratum are pertinently associated with the high-efficiency tunneling requirement of the shield engineering, a set of unified and comprehensive sandy gravel stratum classification method system comprising geological influence factors, an index determination method and index quantitative classification is established, and the blank of a shield characteristic-based sandy gravel stratum classification and grading evaluation system is filled.
(4) The distributed stratum codes of the main influence factors of the sandy cobble stratum shield tunneling are determined, the corresponding relation between the shield characteristics and the stratum codes is established, the stratum codes consisting of 4-bit character codes are obtained, and the influence factors which play a leading role in the sandy cobble stratum shield are conveniently determined from a plurality of indexes of the stratum.
(5) The region to be excavated is quantized into a plurality of levels, and all levels of schemes can be freely combined and superposed on the premise of no conflict. The given classification index is not only used for decomposing the complex properties of the sandy gravel stratum, but also used for merging similar engineering characteristics, and is taken as a ruler as a basis for evaluating the sandy gravel shield characteristics, so that the method is a simple method for engineering evaluation, is convenient for technicians to give a proper construction method, an optimized structural design and reasonable cost control, and has guiding significance for the construction and design of a sandy gravel stratum shield tunnel.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It should be apparent that the drawings in the following description are merely exemplary and that other implementation drawings may be derived from the provided drawings by those of ordinary skill in the art without inventive effort.
The structures, ratios, sizes, and the like shown in the present specification are only used for matching with the contents disclosed in the specification, so that those skilled in the art will understand and read the present invention, and do not limit the conditions for implementing the present invention, so that the present invention has no technical essence, and any modifications of the structures, changes of the ratio relationships, or adjustments of the sizes, should still fall within the scope covered by the technical contents disclosed in the present invention without affecting the efficacy and the achievable purpose of the present invention.
FIG. 1 is a flow chart of a sand and gravel stratum classification method based on shield engineering characteristics according to an embodiment;
FIG. 2 is a schematic diagram of indexes of influence of sand and pebble shield tunneling;
FIG. 3 is a schematic view of the characteristic particle size of a shaft screw conveyor, wherein (a) is a longitudinal section and (b) is a cross section;
FIG. 4 is a schematic view of a characteristic particle size of a belt screw conveyor, wherein (a) is a longitudinal section and (b) is a cross section;
FIG. 5 is a sectional view of the sand and gravel stratum conveying and discharging particle size of a shield body with the outer diameter of more than 6 m;
FIG. 6 is a schematic diagram of the groundwater level height and the limit water level height;
FIG. 7 shows the average quartz contentQ S Graph of the relationship with abrasion value.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the present invention is described in further detail below with reference to the embodiments and the accompanying drawings. The exemplary embodiments and descriptions of the present invention are provided to explain the present invention, but not to limit the present invention.
In the description of the present invention, the terms "comprises/comprising," "consisting of … …," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a product, apparatus, process, or method that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such product, apparatus, process, or method if desired. Without further limitation, an element defined by the phrases "comprising/… …", "consisting of … …" does not exclude the presence of additional like elements in a product, device, process or method that comprises the element.
It is to be understood that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "secured," and the like are intended to be open-ended, i.e., to mean either a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
It will be further understood that the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," "center," and the like are used herein to indicate an orientation or positional relationship based on that shown in the drawings for ease of description and simplicity of description, but do not indicate or imply that the device, component, or structure so referred to must have a particular orientation, be constructed or operated in a particular orientation, and should not be construed as limiting the invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.
The following describes the implementation of the present invention in detail with reference to preferred embodiments.
As shown in fig. 1, the present invention generally provides a sand and gravel stratum classification method based on shield engineering characteristics, and it is expected that by providing qualitative classification descriptions and quantitative classification indexes, the shortcomings of existing sand and gravel classification that only depends on geological factors, engineering experience or a small number of single indexes can be overcome. The judgment basis of the segmentation of the geological condition group of the shield tunnel engineering is increased, the shield construction technical system under the sandy cobble stratum condition is perfected, the pertinence and the scientificity of the shield equipment selection and the shield tunneling technical scheme selection are improved, and the method has guiding significance for the design and the construction of the sandy cobble stratum shield tunnel.
In some embodiments, the classification method comprises the steps of:
the method comprises the following steps: based on the sand and pebble stratum shield construction related engineering characteristics, analyzing the potential technical influence factors of stratum conditions on shield tunneling to obtain four main technical factors influencing the sand and pebble stratum shield tunneling: determining whether particle size factors of crushing in front of a cutter head are needed, whether fine particle content factors of modifying agent for improving muck are needed, whether water pressure high and low factors of spewing of a screw conveyor can be formed, and whether abrasion degree factors of severe abrasion can be generated on a cutter;
step two: determining characteristic indexes of each technical factor and an index determination method;
step three: classifying the sand-gravel stratum according to different shield tunneling technical schemes to be caused by various characteristic indexes and characteristic values thereof, specifically classifying the sand-gravel stratum into sand-gravel capable of being transported and discharged (without crushing) and sand-gravel incapable of being transported and discharged (needing crushing) according to the particle size of the sand-gravel capable of being transported and discharged; the sand-gravel sand can be divided into sand-gravel sand and sand-gravel sand; the sand-gravel separation method can be divided into high-water-pressure sand-gravel and low-water-pressure sand-gravel according to the water pressure; according to the abrasion degree, the sand-gravel sand can be divided into high abrasion sand-gravel and low abrasion sand-gravel;
step four: and (5) acquiring the sand-pebble stratum shield characteristics of the shield tunnel, and providing a corresponding technical scheme according to the classification standard determined in the step three.
In the first step, as shown in fig. 2, according to the prior art and the safety accident reports of multiple subway tunnel constructions in each major metro city built in China, the main indexes affecting the efficient tunneling of the sandy pebble stratum shield are summarized and sorted, the ratio of each index can reflect the potential risk factors of the sandy pebble stratum shield construction, including mineral components, particle size, fine particle content, groundwater pressure and the like, and the ratio of the four indexes exceeds 80%, wherein:
(1) the particle size influences the model selection of the shield machine, the opening rate of a cutter head, the rock breaking mode and the like, and large-particle-size cobble stones can cause cutter head system faults such as cutter damage, cutter head deformation, clamping of a spiral conveyor and the like.
(2) The fine particle content influences the gradation and permeability of the stratum, further influences the deformation of the stratum and influences the muck improving method. The mud cake phenomenon is easily caused under the condition of high fine particle content.
(3) The underground water condition influences the sand and pebble shield tunneling method, the muck improvement performance and the like. The stratum with strong water and permeability brings the risks of tunnel face collapse, gushing and the like.
(4) The abrasive mineral content is a decisive index for causing the abrasion of the shield cutter head and the cutter, and the high-content quartz rock powder can cause great abrasion to the shield cutter head, the cutter and the pipeline of the screw conveyer. Frequent machine halt and tool change greatly affect the tunneling efficiency.
Therefore, according to the collected potential risk factors of the sandy gravel stratum shield construction, four main influence factors influencing the sandy gravel stratum shield construction are determined as follows: particle size, fine content, water pressure level, and degree of erosion.
Characteristic indicators of particle size include: maximum particle size of pebblesd max Maximum passing capacity of screw conveyerd p ；
The determination method comprises the following steps: maximum particle diameter of pebblesd max Obtaining through a survey report; maximum throughput capacity of screw conveyord p Calculated by the form of the screw conveyer and the size of the conveying opening and depends on the inner diameter of the conveying cylinder of the screw conveyerD 1 To the outer diameter of the shaft of the screw conveyerD 2 、D 3 Single sided loop bandwidth therebetweend x And net pitchl x Of shaft and belt screw conveyorsd x 、l x The following equation (1) and equation (2) respectively determine:
In the formula (I), the compound is shown in the specification,D 2 、D 3 respectively are the shaft outer diameter of a shaft type screw conveyer and the shaft outer diameter of a belt type screw conveyer,pin order to obtain the pitch of the helical blades,tis the thickness of the helical blade whend x /l x ≥1Maximum throughput of screw conveyord p =d x (ii) a When the temperature is higher than the set temperatured x /l x ＜1Maximum throughput of screw conveyord p =l x 。
The characteristic indicators of the fine particle content include: mass ratio of fine particles with particle size less than 75um in stratumd 75 ；
The determination method comprises the following steps: sampling is carried out in the shield region, and particle size analysis tests are carried out according to a screening method given in the geotechnical test method standard GB/T50123 and 2019. And calculating the mass percentage (%) of fine particles having a particle diameter of less than 75um in the sample to the total mass of the sample by the following formula:
In the formula:
-mass of fines (g) with a particle size of less than 75 um;m d -total mass (g) of samples taken while carrying out the sieve analysis test.
The characteristic indexes of the water pressure include: height of ground water levelh w Limit water level heighth 0 ；
The determination method comprises the following steps: the construction of a horizontal line at the elevation of the bottom of the soil bin of the shield tunneling machine is taken asxThe shaft is provided with a plurality of axial grooves,xthe intersection point of the shaft and the excavation surface in the soil bin is an original point, a position water head at the original point is set to be 0 through a coordinate system taking an original point plumb line as a y axis, and the height of the underground water level is set to be 0h w (FIG. 6), the limit water level height is set at the position 1m above the rear gate of the screw conveyorh 0 According toh w Andh 0 the position relationship of the water pressure sensor can judge the underground water pressure condition of the stratum.
In the second step: the characteristic indicators of the degree of abrasion include: average content of quartzQ S ；
The determination method comprises the following steps: according to shield interval geological exploration data, obtaining interval stratum quartz average content, and according to data point fitting, obtaining quartz average contentQ S And abrasion valueA C The linear regression relationship of (1):
The third step is as follows: according to the maximum particle diameter of pebblesd max Maximum capacity of screw conveyerd p The relationship (a) of (b) is to divide the sandy gravel stratum into two types, as shown in table 1, fig. 5 is a stratum transportation and discharge particle size partition diagram when a shield machine (shaft type maximum throughput capacity 415mm, belt type maximum throughput capacity 700 mm) with an outer diameter of more than 6m is used for tunneling.
TABLE 1 Sand gravel formation particle size classification
| Categories | Description of the nature | Quantitative index | Control measures |
| First kind | Sand and pebble stratum not able to be broken | d max ≥d p | Crushed conveying line |
| Second class | Sand and gravel stratum capable of being transported and discharged without being broken | d max ＜d p | Direct warehousing and conveying line |
The first type: non-dischargeable (need to be broken) sandy gravel stratum:d max ≥d p 。
the rock breaking cutter capable of breaking the large boulder is configured, a tunneling mode of 'breaking wedging and conveying and discharging' is adopted according to the principle of 'breaking to the greatest extent, breaking large blocks and conveying and discharging' and the large-particle-size boulder is broken into particles smaller than the maximum passing capacity of the screw conveyor through the rock breaking cutter. The opening rate of the cutter head is at least over 35 percent, and is preferably in a panel type or a radial plate type; the design of the cutter is mainly based on 'impact resistance and loss reduction'; the low penetration and high rotation speed are adopted, and the cutter head torque is larger than 5000kN ∙ m. In addition, the diameter of the cylinder can be increased, the screw pitch can be enlarged, the shaft diameter can be reduced or a shaftless belt type screw conveyor can be adopted for optimization design to increase the diameterd p Is determined. The design of the screw conveyor is optimized to improve the conveying and discharging passing rate and reduce the crushing amount, and measures such as increasing the opening of the cutter head and intercepting the grating can be adopted for limiting.
The second type: the sand and gravel stratum can be transported and discharged (without being broken):d max ＜d p 。
pebbles and gravels in the stratum can be directly put into a bin for conveying and discharging without being crushed, and a wedge plough and conveying and discharging tunneling mode is adopted according to the principle of wedge plough-loosening-stripping excavation and integral conveying and discharging. The size of the opening of the cutter is as large as possible, so that rapid bin entry is realized, and excessive follow-up rotation in front of the cutter is avoided, so that the torque is increased, and excessive cutter abrasion or impact damage is caused; the shield driving adopts a driving mode suitable for adopting low speed and high torque.
In the third step: according to the mass ratio of fine particles with the particle diameter of less than 75umd 75 The sand and gravel formations were divided into two categories, as shown in table 2.
TABLE 2 Sand gravel formation fines content classification
| Categories | Description of the nature | Quantitative index | Control measures |
| First kind | High-viscosity particle content low-permeability sandy gravel stratum | d 75 ≥30% | Improvement of foaming agent and water |
| Second class | High permeability sandy gravel formation with low viscous particle content | d 75 ＜30% | Improvement of' mud material + foaming agent |
The first type:d 75 ≥30%a low permeability sandy-pebble formation of high viscous particle content;
the stratum has high fine particle content, poor permeability, poor fluidity and high adhesion, and is easy to form mud cakes during shield construction. The improvement of the dregs needs to take a surface active material (foam) and water as main improvement materials, increase the fluidity of the dregs, reduce the adhesion and prevent the dregs from being bonded on a cutter head and the wall of a soil bin to form mud cakes.
The second type:d 75 ＜30%a highly permeable sandy gravel formation of low viscous particle content;
the fine particle content of the stratum is low, the viscosity is low, the water permeability is strong, the workability is poor, and the slag soil improvement needs to be injected with modifier additives such as mineral slurry materials (bentonite and clay) such as bentonite and clay and foaming material agents to supplement the fine particle content and adjust the gradation to form a mud film, thereby improving the fluidity and the water stopping performance. Under the condition, the stratum can be further divided into high water pressure stratum and low water pressure stratum according to the magnitude of the underground water pressure.
In the third step: in a highly permeable sandy gravel stratum, according to the height of underground water levelh w Limit water level heighth 0 The subsurface water occurrence characterized subdivides the sandy gravel formation into two categories, as shown in table 3, including:
TABLE 3 Sand and pebble formation water pressure size classification
The first type:h w ≥h 0 high hydraulic pressure sand gravel formation;
as shown in fig. 6, the water pressure is determined according to the groundwater level height and the limit water level height. The limit water level is at +1m height at the screw conveyor outlet. If the groundwater level is above the threshold level, then in formations with low fines content (high permeability), gushing is likely to occur. At the moment, the super absorbent resin and the foaming agent are used as main improved materials, the water absorption capacity of the super absorbent resin can reduce the inter-granular gaps, so that the soil body is changed into a gel state, the cohesiveness and the water stopping performance of the muck are improved, and the shield spiral conveyor in the high-water-pressure stratum is prevented from gushing.
The second type:h w ＜h 0 low water pressure sand gravel formation;
if the underground water level is lower than the limit water level, the phenomenon of surging can not happen normally, and the bentonite slurry and the foaming agent are adopted as main improvement materials for improving the slag soil, so that the plastic fluidity and the cohesiveness of the slag soil are increased, the frictional resistance is reduced, and the torque of a cutter head is reduced.
In the third step: according to the average quartz contentQ S The degree of abrasion was divided into two categories, as shown in table 4.
TABLE 4 sand and gravel formation abrasiveness Classification
The first type:Q S ≥80%(ii) a A highly abrasive sandy gravel formation;
as shown in fig. 7, the degree of formation erosion is determined based on the average quartz content of the formation. For the highly abrasive sandy gravel stratum, in order to reduce the abrasion of a shield cutter and prolong the service life of the cutter, the abrasion resistance of a cutter disc and the cutter needs to be improved in practical engineering, a super-high abrasion-resistant high-strength wedge plough cutter is used, and the cutter is configured in a multi-layer echelonment mode; the opening rate of the cutter head and the grain diameter of the spiral conveyor which can convey and discharge are increased, the complete discharge is realized, and the 'discharge stagnation' phenomenon of pebble grains in the front of the cutter head, the soil bin and the spiral conveyor is reduced; the erosion and abrasion prevention abrasion control method and the high penetration and low rotation mode tunneling are adopted, so that the impact damage of the cutter is reduced, and the conventional abrasion coefficient of the cutter is reduced. The foaming agent and the bentonite slurry are used as main improved materials to wrap and lubricate the sand and pebble particles, so that the internal friction angle is reduced, and the cutter abrasion is reduced.
The second type:Q S ＜80%(ii) a A weakly abrasive sandy gravel formation;
the shield tunneling machine has the advantages that the shield tunneling machine improves the shield propelling speed and the cutter head rotating speed, namely, the shield tunnels at a higher propelling speed and a higher cutter head rotating speed, properly reduces the cutter layering and cutter arrangement quantity, reduces the cutter head torque and improves the tunneling efficiency.
In the invention, the influence of the above characteristics of the sand and pebbles on shield tunneling is comprehensively considered, and the four-dimensional coding of the sand and pebble stratum under the influence of four factors is established by representing the particle size, the fine particle content, the water pressure height and the abrasion degree. The stratum code is composed of 4-bit character codes, the 1 st digit represents the fine grain content, the 2 nd digit represents the water pressure, the 3 rd digit represents the abrasion degree, and the 4 th digit represents the particle size, wherein each digit is divided into two grades of 1 and 2 according to the degree from weak to strong. For example, for a high permeability-high water pressure-strong abrasion-migrateable formation, the formation is encoded as 2221. The method considers the sand and pebble shield engineering characteristics under the combination of multiple factors and can guide the engineering construction.
And establishing a corresponding relation between the shield engineering characteristics and the stratum codes, and conveniently determining the influence factors which play a leading role in the sand and gravel stratum shield from a plurality of indexes of the stratum. The accuracy of the stratum classification and the corresponding construction scheme is verified through stratum coding and shield engineering embodiments under several typical combination indexes shown in table 5.
Table 5 stratum coding and shield construction engineering examples under combined indexes
In example 1, the shield engineering is characterized by high permeability-low water pressure-strong abrasion-non-dischargeable stratum, the stratum code is 2122, and according to the classified particle size classification, fine particle content classification, water pressure high and low classification and abrasion degree classification, the construction scheme is determined as follows: adopting a tunneling mode of 'large block crushing and integral conveying and discharging'; a combined cutter head, wherein the opening rate of the cutter head is 45%; the cutter adopts the combination of a center cutter, a pilot cutter, a scraper and a hobbing cutter and adopts a tooth shape staggered continuous arrangement mode. The cutter material adopts E5 hard alloy with better bending resistance and tensile strength; a belt type spiral conveyor with the outer diameter of 900mm and without a central shaft is adopted, the maximum discharge particle size reaches 640mm multiplied by 1000mm, and the rated torque is 5380kN ∙ m; the method adopts a 'muddy water + foam' residue soil improvement measure to overcome the adverse conditions of the anhydrous large-particle-size cobble stratum.
In example 2, the shield construction is characterized by high permeability-low water pressure-strong abrasion-drainage layer, the stratum code is 2121, and the construction scheme is determined according to the classified particle size classification, the fine particle content classification, the water pressure high-low classification and the abrasion degree classification: mainly adopts a wedge plough and conveying and discharging tunneling mode; a composite cutter head is adopted, and the opening rate is 40%; arranging a hob (with the height of 187.7 mm), a cutter (with the height of 130 mm), a scraper and the like; the cutter head is made of E5 materials, so that the wear resistance of the cutter is improved; rated torque 6000kN ∙ m; the spiral conveyer is in a belt type, and the maximum passing capacity is 670mm (the maximum particle size of pebbles is 450 mm); the residue soil improvement adopts 'bentonite + foam + water', and the engineering effect is good.
In example 3, the shield construction is characterized by high permeability-high water pressure-weak abrasion-dischargeable stratum, the stratum code is 2211, and according to the classified particle size classification, the fine particle content classification, the water pressure high-low classification and the abrasion degree classification, the construction scheme is determined as follows: a spoke type cutter head is adopted, the opening rate of the cutter head is 63%, and hard alloy wear-resistant grids are welded on an outer shaft of the cutter head; a first knife, a shell knife, a scraper and the like are arranged, and no tearing knife is arranged; cutterhead torque 4950kN ∙ m; the screw conveyer is of an axial type, and the maximum passing capacity is 300mm (the maximum particle size of pebbles is 110 mm); the bentonite slurry is adopted for improving the slag soil, and the engineering effect is excellent.
In example 4, the shield construction is characterized by high permeability-high water pressure-strong abrasion-transportable layer, the stratum is coded as 2221, classified according to the classified particle size, fine content, water pressure, and abrasionGrading the degree, and determining a construction scheme as follows: a composite cutter head is adopted, the opening rate of the cutter head is 34%, an anti-abrasion protective layer is welded on the surface of the cutter head, grid-shaped anti-abrasion hard alloy is welded on the periphery of a ring beam in a surfacing mode, the tunneling speed is 15-30 mm/min, and the torque of the cutter head is not more than 2000kN ∙ m; configuring 8 central tearing cutters, hobbing cutters and scrapers; a hard alloy cutter is adopted, and hobs are arranged on the edge of the hard alloy cutter, so that the rock breaking capacity and strength of the cutter head are enhanced; the screw conveyer adopts a belt type and can convey the pebbles with the maximum grain diameter of 520mm multiplied by 290mm (the maximum grain diameter of 60 mm); the residue soil improvement is to add viscosity increaser CMC and dispersant sodium carbonate (Na) into the bentonite slurry 2 CO 3 ) The effect is good.
In example 5, the shield construction is characterized by low permeability-high water pressure-strong abrasion-drainage layer, the stratum code is 1221, and the construction scheme is determined according to the classified particle size classification, the fine particle content classification, the water pressure high-low classification and the abrasion degree classification: a composite cutter head is adopted, and the opening rate is 35%; the cutter is arranged in a gradient manner, the hob is 184mm higher than the panel, the cutter is 140mm higher than the panel, and the edge scraper is 145mm higher than the panel, so that the effect of reducing the cutter abrasion is achieved. The slag soil improvement material is 'bentonite slurry + cement', and the workability and the water resistance of the slag soil are improved.
In example 6, the shield construction is characterized by low permeability-high water pressure-strong abrasion-non-drainage layer, the stratum code is 1222, and the construction scheme is determined according to the classified particle size classification, the fine particle content classification, the water pressure high and low classification and the abrasion degree classification: adopting an earth pressure balance shield, four spoke plate type combined cutterheads with four width and four panels, wherein the opening ratio of the cutterheads is 35%; tool configuration: the hob adopts a widened cutting edge, and a wear-resistant layer is welded on the hub part of the hob; the cutter and the edge scraper are designed by alloy so as to improve the wear resistance; the lower rotating speed (1.1-1.3 r/min) of the cutter head is adjusted, and the rated torque is 6848 kN; the slag soil improvement material adopts foam and bentonite slurry, so that the stratum water permeability is reduced, and better fluidity and water stopping property are obtained.
In example 7, the shield construction is characterized by high permeability-high water pressure-strong abrasion-non-drainage layer, the stratum code is 2222, and the construction scheme is determined according to the classified particle size classification, the fine particle content classification, the water pressure high-low classification and the abrasion degree classification: a mixed cutter head is adopted, the opening rate is 35%, the whole surface of the cutter head is fully paved with wear-resisting plates, and the rated torque is 6190kN ∙ m; the cutter is provided with a heavy tearing knife for crushing boulders with large particle size, a wedge coulter, a scraper and a knife holder device with the interchanging of the scraper and the tearing knife. A cutter distribution mode of multi-point balance configuration of various cutters is adopted; the screw conveyer is of a shaft type, and the maximum passing particle size is 300mm (the maximum particle size of pebbles reaches more than 800 mm); the muck improvement material adopts sodium bentonite, foam and high molecular polymer, applies muck improvement technology with high damping characteristic (slurry consistency is more than 120 s), and has good engineering effect.
The invention discloses a sand and gravel stratum classification method based on shield engineering characteristics, which is used for guiding construction, perfecting a shield construction evaluation system of a sand and gravel stratum complex geological environment, providing qualitative classification description and quantitative grading indexes, enabling the sand and gravel tunnel shield construction measures to be more targeted, effectively guiding and solving the series construction problems encountered by the sand and gravel stratum, further promoting standardized and standardized construction under sand and gravel geological conditions, making up the defect that the classification is carried out only by depending on geological exploration, engineering experience or a small amount of single indexes in the prior evaluation technology, and providing scientific basis for long-distance efficient tunneling of the sand and gravel stratum. The sand and gravel stratum classification method provided by the invention has guiding significance for the construction and design of a sand and gravel stratum shield tunnel.
It will be readily appreciated by those skilled in the art that the above-described preferred embodiments may be freely combined, superimposed, without conflict.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (10)
1. A sand and gravel stratum classification method based on shield engineering characteristics is characterized by comprising the following steps:
the method comprises the following steps: based on the sand and gravel stratum shield construction engineering characteristics, potential technical factors of stratum conditions influencing shield tunneling are analyzed, and four main technical factors influencing sand and gravel stratum shield tunneling are obtained: the factors of particle size of broken before a cutter head, fine particle content of improved muck by adding a modifying agent, water pressure of gushing of a screw conveyor and abrasion degree of severe abrasion of the cutter are required;
step two: determining characteristic indexes of each technical factor; wherein, the characteristic indexes of the particle size comprise: maximum particle size of pebblesd max Maximum passing capacity of screw conveyerd p The characteristic indicators of the fine particle content include: mass ratio of fine particles with particle size less than 75um in stratumd 75 The characteristic indexes of the water pressure level comprise: height of ground water levelh w Limit water level heighth 0 The characteristic indicators of the degree of abrasion include: average content of quartzQ S ；
Step three: classifying the sandy gravel stratum according to different shield tunneling technical schemes to be caused by various characteristic indexes, and matching tunneling technical measures according to stratum classification; wherein
According to maximum particle size of pebblesd max Maximum capacity of screw conveyerd p The relationship of (a) to (b) divides the sandy gravel formation into two categories: the first type:d max ≥d p the sand and gravel stratum which needs to be crushed cannot be transported and discharged; the second type:d max ＜d p the sand-gravel stratum can be transported and discharged without being crushed;
according to the mass ratio of fine particles with the particle diameter of less than 75umd 75 The sand and gravel stratum is divided into two types: the first type:d 75 ≥30%a low permeability sandy-pebble formation of high viscous particle content; the second type:d 75 ＜30%a highly permeable sandy gravel formation of low viscous particulate content;
in a highly permeable sandy cobble stratum, according to the height of underground water levelh w Limit water level heighth 0 The characteristic occurrence condition of underground water is that the sandy cobble stratum is secondarily subdivided into two types: the first type:h w ≥h 0 high hydraulic pressure sand gravel formation; the second type:h w ＜h 0 low water pressure sand gravel formation;
according to the average quartz contentQ S Sand and gravel strata are divided into two categories: the first type:Q S ≥80%(ii) a A highly abrasive sandy gravel formation; the second type:Q S ＜80%(ii) a A weakly abrasive sandy gravel formation;
step four: and (4) acquiring the shield engineering characteristics of the sandy gravel stratum of the shield tunnel, and providing a corresponding construction scheme according to the classification standard and the tunneling technical measures determined in the step three.
2. The classification method according to claim 1, wherein in step two:
the method for measuring the characteristic index of the particle size comprises the following steps: maximum particle size of pebblesd max Obtaining through a survey report; maximum throughput capacity of screw conveyord p Calculated by the form of the screw conveyer and the size of the conveying opening and depends on the inner diameter of the conveying cylinder of the screw conveyerD 1 To the outer diameter of the shaft of the screw conveyerD 2 、D 3 Single sided loop bandwidth therebetweend x And net pitchl x Of shaft and belt screw conveyorsd x 、l x The following equation (1) and equation (2) respectively determine:
In the formula (I), the compound is shown in the specification,D 2 、D 3 respectively are the shaft outer diameter of a shaft type screw conveyer and the shaft outer diameter of a belt type screw conveyer,pthe pitch of the helical blades is set as follows,tis the thickness of the helical bladed x /l x ≥1Maximum throughput of screw conveyord p =d x (ii) a When in used x /l x ＜1Maximum throughput of screw conveyord p = l x 。
3. The classification method according to claim 1, wherein in step two:
the method for measuring the characteristic index of the fine particle content comprises the following steps: sampling in a shield interval, carrying out a particle size analysis test, and calculating the percentage of the mass of fine particles with the particle size of less than 75um in the sample to the total mass of the sample by the formula (3):
In the formula:
-mass of fines (g) with a particle size of less than 75 um;m d -total mass (g) of samples taken while carrying out the sieve analysis test.
4. The classification method according to claim 1, wherein in step two:
the method for measuring the characteristic indexes of the water pressure height comprises the following steps: the horizontal line at the elevation of the soil bin bottom of the shield tunneling machine is establishedxThe shaft is provided with a plurality of axial grooves,xthe intersection point of the shaft and the excavation surface at the soil bin is an original point, a position water head at the original point is set to be 0 through a coordinate system with the original point plumb line as a y-axis, and the height of the underground water level is set to be 0h w Setting the height of water level at the position 1m above the rear gate of the screw conveyor as a limith 0 。
5. The classification method according to claim 1, wherein in step two:
the method for measuring the characteristic index of the abrasion degree comprises the following steps: according to shield interval geological exploration data, obtaining interval stratum quartz average content, and according to data point fitting, obtaining quartz average contentQ S And abrasion valueA C The linear regression relationship of (1):
6. The classification method according to claim 1, characterized by the following steps:
for a first type of sand and gravel stratum which cannot be drained and needs to be broken, a wedge impact-drainage tunneling mode is adopted according to the principle of breaking completely, breaking large blocks and integrally draining;
for the second type of sand-gravel stratum which can be transported and discharged without crushing, a wedge plough-loosening-stripping excavation and integral transportation and discharge principle is followed, and a wedge plough-transportation and discharge tunneling mode is adopted.
7. The classification method according to claim 1, characterized by the following steps:
for the first low-permeability sandy gravel stratum with high viscous particle content, the foaming agent and water are used as main improved materials, so that the flowability of the muck is increased, the adhesion is reduced, and the muck is prevented from being bonded on a cutter head and the wall of a soil bin to form mud cakes;
for the second type of high-permeability sandy gravel stratum with low-viscosity particle content, bentonite or clay mineral mud and a foaming agent are used as main improvement materials to supplement the content of fine particles, improve the fluidity and improve the water stopping property.
8. The classification method according to claim 7, characterized by the following steps:
for the first kind of high-water-pressure sand gravel stratum, high-water-absorption resin and foaming agent are used as main improved materials, the high-water-absorption resin can reduce the inter-particle gaps, the soil body is changed into a gel state, the cohesiveness and the water stopping performance of the muck are improved, and the shield spiral conveyor of the high-water-pressure stratum is prevented from gushing;
for the second low-water-pressure sand-gravel stratum, bentonite slurry and a foaming agent are adopted as main improved materials, so that the plastic fluidity and the cohesiveness of the slag soil are increased, the frictional resistance is reduced, and the torque of a cutter head is reduced.
9. The classification method according to claim 1, characterized by the following steps:
for the first type of strongly abrasive sandy gravel stratum, an ultrahigh wear-resistant high-strength wedge plough cutter is used, and the cutter is configured in a multi-layer echelonment manner, so that the wear resistance of the cutter head and the cutter is improved; the opening rate of the cutter head and the grain diameter of the spiral conveyor which can convey and discharge are increased, the complete discharge is realized, and the 'discharge stagnation' phenomenon of pebble grains in the front of the cutter head, the soil bin and the spiral conveyor is reduced; the erosion-resistant and abrasion-reducing wear control method and the high-penetration low-rotation-speed mode are adopted for tunneling, so that the impact damage of the cutter is reduced, and the conventional wear coefficient of the cutter is reduced; the foaming agent and the bentonite slurry are used as main improved materials to wrap and lubricate the sand and pebble particles, so that the internal friction angle is reduced, and the cutter abrasion is reduced;
for the second type of weak abrasive sandy gravel stratum, the shield propelling speed and the cutter head rotating speed are improved, the number of cutter layering and cutter arrangement is properly reduced, the cutter head torque is reduced, and the tunneling efficiency is improved.
10. The classification method according to claim 1, wherein step four comprises:
(1) distributing stratum codes to four main technical factors, wherein the 1 st digit represents the content of fine particles, the 2 nd digit represents the water pressure, the 3 rd digit represents the abrasion degree, the 4 th digit represents the particle size, and each digit is divided into two grades of 1 and 2 according to the degree from weak to strong;
(2) acquiring the shield engineering characteristics of the sandy cobble stratum of the shield tunnel, establishing the corresponding relation between the shield engineering characteristics and stratum codes, and acquiring the stratum codes consisting of 4-bit character codes;
(3) and (4) providing a corresponding technical scheme according to the stratum classification standard and the tunneling technical measure determined in the third step and by combining stratum coding.
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| CN103102886A (en) * | 2013-01-11 | 2013-05-15 | 北京城建集团有限责任公司 | Muck modifier guaranteeing smooth tunneling of shield tunneling machine |
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| CN113775347A (en) * | 2021-11-10 | 2021-12-10 | 北京城建集团有限责任公司 | Muck improvement method based on cobble rock stratum shield engineering characteristic classification |
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| CN109933577B (en) * | 2019-03-08 | 2020-12-18 | 山东大学 | Tunnel tunneling prediction method and system based on TBM rock-machine parameter dynamic interaction mechanism |
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|---|---|---|---|---|
| CN103102886A (en) * | 2013-01-11 | 2013-05-15 | 北京城建集团有限责任公司 | Muck modifier guaranteeing smooth tunneling of shield tunneling machine |
| CN105201520A (en) * | 2015-09-09 | 2015-12-30 | 北京市市政四建设工程有限责任公司 | Muck improvement technology for earth pressure balance shield construction in sandy cobble stratum |
| CN207598243U (en) * | 2017-12-21 | 2018-07-10 | 中铁二十一局集团轨道交通工程有限公司 | A kind of shield driving anti-spouting device |
| CN109339799A (en) * | 2018-10-26 | 2019-02-15 | 中铁二十二局集团轨道工程有限公司 | A kind of rich water sand-pebble layer Shallow Section shield-tunneling construction technique |
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| CN110566211A (en) * | 2019-09-04 | 2019-12-13 | 中交一公局第三工程有限公司 | Earth pressure shield muck flow plasticity improvement method suitable for sandy gravel stratum |
| CN112949043A (en) * | 2021-02-07 | 2021-06-11 | 中交第三航务工程局有限公司南京分公司 | Sand-gravel stratum shield tunnel geological evaluation method |
| CN113775347A (en) * | 2021-11-10 | 2021-12-10 | 北京城建集团有限责任公司 | Muck improvement method based on cobble rock stratum shield engineering characteristic classification |
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