Stratum consolidation PSC construction method
Technical field
The present invention relates to stratum consolidation construction field, particularly relate to a kind of stratum consolidation PSC construction method.
Background technology
Domestic tunneling shield construction termination and building stratum consolidation method are mainly with the main reinforcement means such as modified form, displaced type, extrusion pressing type.Prior art is by rotary churning pile, sleeve valve barrel grouting to reach stratum consolidation object, and for rich water sandy pear variety, existing reinforcement means there is no a kind of safe, economic, efficient, ripe reservoir treating construction method.
Domestic prior art relevant to invention at present has one.For application people is China Railway Erju Co., Ltd and China Railway Erju 1st Engineering Co., Ltd., number of patent application is the patent of invention " construction method of soft clay area ground stabilization " of 201110064110.0, the invention discloses a kind of soft clay area foundation stabilization construction method, adopt following steps: construction equipment prepares; Construction plant prepares; The steps such as surveying and locating.Current this construction method only perforate grouting behind shaft or drift lining on the ground, does not improve soil layer, and the bulk strength after construction does not obtain the improvement of essence, and this construction method cannot meet now more and more higher construction requirement.
Summary of the invention
The technical problem to be solved in the present invention is to provide that a kind of construction effect is good, applied widely, environmental pollution is few, construction safety and stratum consolidation PSC construction method with low cost.
In order to solve technical problem proposed by the invention, the invention discloses a kind of stratum consolidation PSC construction method, this stratum consolidation PSC construction method comprises following construction sequence:
A, the setting-out of position, hole: construction before according to designing requirement total powerstation to the position setting-out of each hole, through repetition measurement test line qualified after, position on ground;
B, the first hole construction: use rig to carry out the first hole bore operation, drilling process wants microrunning, grasping stratum in operation process affects situation to rig, and determine the drilling parameter under this formation condition, stratum geological condition is determined in test simultaneously;
C, determine wet end furnish: reinforce wet end furnish according to reinforcing area stratum geological condition determination draining chemical sizwe proportioning and the filling perforation of grouting grouting;
D, layer drainage construction: reuse underground drill rig and carry out bore operation, while bit drills to reinforcing area, using grouting pump to determine, the chemical sizwe of proportioning injects in reinforcing area, until arrive design hole depth;
E, stratum consolidation slip casting: use grouting pump filling perforation to be reinforced in the reinforcing area completing stratum draining that slurry implantation step d obtains;
F, repetition steps d, e can complete whole stratum consolidation PSC construction sequence.
Stratum consolidation PSC construction method disclosed by the invention is different from original form of construction work, and first formation is carried out analysis and made construction more targeted, and behind analysis stratum, configures corresponding slurry workmanship according to stratum geological condition be guaranteed further; Carry out a stratum draining in the process of boring under underground drill rig drill bit and can get rid of stratum moisture content, improve the impermeability of the soil body; Reinforce slurry according to the filling perforation obtained after the geological condition of analysis stratum can change former physical properties of soil and improve the compressive strength of the soil body, finally make weak soil layer (especially chiltern, gravelly clay and layer of sand) become the reinforcing body that impermeability is high, compressive strength is high and stability is high.
As a modification of the present invention: described draining chemical sizwe comprises water glass and phosphoric acid.Water glass and phosphoric acid are conventional industrial materials, can effectively reduce cost of production.
As a modification of the present invention: described grouting filling perforation is reinforced slurry and comprised water glass and cement paste.Water glass and cement paste are conventional constructional materialss, can effectively reduce cost of production.
As a modification of the present invention: the bore operation in described ground layer drainage construction step is carried out to opposite side by the side of working face, completes stratum draining successively.Carried out holing to opposite side by the side of working face, stratum draining can ensure the water in stratum once to get rid of to opposite side from side, this form of construction work can obtain the substantially unified stratum of parameter, can improve construction quality.
As a modification of the present invention: described consolidation grouting process is carried out after ground layer drainage construction all completes, described consolidation grouting process is carried out to central area by working face periphery.Stratum consolidation slip casting is reinforce slurry due to filling perforation to have swelling in the process of solidifying by peripheral the carrying out to central area of working face, carried out can ensureing can not reinforce the expansion in slurry process of setting due to filling perforation in the process of construction to central area by periphery and destroy the stratum of having constructed around working face, affecting the outer stratum of construction area and stablize.
As a modification of the present invention: described consolidation grouting process upwards promotes by bottom hole, hoisting velocity need according to flow rate of grouting and grouting amount and the adjustment of slip casting penetration radius.The control of hoisting velocity can ensure slip casting effect, avoids slurries make slurries deficiency in hole form cavity very little or stablize because slurries too much destroy stratum here.
As a modification of the present invention: complete when after chemical sizwe is injected the step of hole by the consolidation grouting of described step e in completing steps d, drill bit of drilling machine promotes.Inject filling perforation reinforcing slurry in the process that underground drill rig drilling rod promotes after completing chemical sizwe injection hole and effectively can shorten the engineering time, stratum draining and stratum consolidation slip casting can complete when underground drill rig one-stop operation.
As a modification of the present invention: described underground drill rig bore operation is carried out to central area by working face periphery, and need to detect stratum geological condition in the process of bore operation, the proportioning of slurry is reinforced in base area layer parameter adjustment chemical sizwe and filling perforation.Detect stratum geological condition during bore operation and adjust according to stratum geological condition the proportioning that chemical sizwe and filling perforation reinforce slurry at any time and effectively can ensure construction quality, construction effect is better.
As a modification of the present invention: described stratum consolidation slip casting process underground drill rig drilling rod hoisting velocity need according to flow rate of grouting and grouting amount and the adjustment of slip casting penetration radius.
As a modification of the present invention: described grouting pump is Double-liquid mud-injection pump.Double-liquid mud-injection pump can complete the slip casting of two kinds of slurries.
Generally speaking the present invention has following beneficial effect:
1, general utility functions
Local layer reinforcement means uses equipment size less, and position, equipment moving hole is flexible; The slurry consolidation time can adjust according to actual conditions; Slurry infiltration is good; Slurries can when circulating water consolidation, slurries are not soluble, and stagnant water effect is good; Reinforcement means is applicable to all kinds of stratum, applied widely;
2, environment-friendly function
The slurries that this stratum consolidation method adopts are to underground water nontoxic pollution-free, and slurries do not run off, and substantially do not produce mud, and without the need to mud outward transport, environment pollution is little;
3, safety work function
Implement is simple, and plant equipment is moved conveniently at work plane, flexible operation, and construction safety is controlled; Consolidation effect is desirable, meets the construction requirements such as stratum consolidation, building strengthening, the reinforcing of tool changing point, the reinforcing of shield-tunneling construction termination;
4, speed of application is fast
Adopt this technology to construct, construction technology divides protrusive and retrusive construction, without the need to drawing hole in addition, saving and drawing the hole time in addition, avoiding collapse hole to occur.Preparation of construction is simple, can carry out operation in 24 hours;
5, engineering cost
This engineering construction equipment is simple, and equipment turnover field expense is less; Equipment operating simple and flexible, constructor is less; Construction material waste rate is lower, saves waste of material cost.
Detailed description of the invention
Need to carry out safety technics to constructor before stratum consolidation construction to tell somebody what one's real intentions are, on-the-spot outfit technician guiding construction, is equipped with professional captain and operates ruggedized equipment.Need in work progress to be equipped with site operation person, guarantee that the technology competitions such as the slip casting degree of depth, grouting amount, grout coordinate ratio and slurry consolidation time meet construction technical requirement.Constructor need focus on the relevant knowledges such as safety management, quality control, environmental protection in addition.
Preparation of construction comprises following several step:
1. enclosing construction
Formally march into the arena before construction, first carry out enclosing construction, and carry out roadblock and security warning.Inside enclosing, put sandbag simultaneously, prevent other road surfaces of mud contamination of being scattered;
2. pipeline detection
Advanced row pipes investigation, if this region is without pipeline, constructs; If there is pipeline, then excavate trial trench, definitely the orientation of underground pipelines, and carry out safeguard measure;
3. construction site layout
Before construction, place is arranged, determine the best putting position of plant equipment and material;
4. position, hole setting-out
Before construction according to designing requirement total powerstation to the position setting-out of each hole, through repetition measurement test line qualified after, position on ground with steel nail, ensure that stake holes center shift variance is less than 50mm.
According to designing requirement after preparation before completing construction, by rig mating holes position, vertical angle creeps into, and require that the biased difference in hole is ± 3cm, incident angle deviation is not more than 1 °.Behind mating holes position, rig must not be shifted, also must not arbitrarily landing.
Underground drill rig carries out the first hole construction behind location, wants microrunning during the first hole construction, and grasping stratum affects situation to rig, and to determine the drilling parameter under this formation condition, stratum geological condition is determined in test simultaneously.Close observation spilling water water outlet situation, when there is a large amount of spilling water water outlet, should stop immediately to bore, construct after analyzing reason again.Often creep into one section, check one section, rectify a deviation in time, position at the bottom of hole should be less than 30cm.
The proportioning of slurry is reinforced according to the stratum geological condition determination draining chemical sizwe obtained and grouting filling perforation, prepare water glass solution I, water glass solution II, phosphoric acid solution, the cement paste of constitutional chemistry slurry according to proportioning after determining proportioning, water glass solution I, water glass solution II, phosphoric acid solution are contained in solution tank for subsequent use, and cement paste scene at any time mixing uses.
After determining wet end furnish, during note chemical grout, be connected with the solution tank of water glass solution I by a wherein pulp-absorbing pipe of Double-liquid mud-injection pump, another root pulp-absorbing pipe is connected with the solution tank of phosphoric acid solution; When slurry is reinforced in note filling perforation, the cement grout mixing bucket that a pulp-absorbing pipe and the filling perforation of Double-liquid mud-injection pump are reinforced is connected, and another root pulp-absorbing pipe is connected with the solution tank of water glass solution II; All have two grouting pipes when noting different slurry, two grouting pipes are connected with the biliquid drilling rod of underground drill rig by two fluid grouting water tap.
The estimation equation of grouting amount of the present invention is undertaken by following formula:
Q=Anα
In formula: Q----grouting amount (m
3);
A----range of grouting volume (m
3);
N----porosity;
α----slurries filling rate.
Here is the embodiment of ground layer drainage construction and stratum consolidation slip casting, and by two kinds of different embodiments, the invention will be further described.
embodiment 1
Stratum drainage construction is carried out after determining proportioning, reuse underground drill rig and carry out bore operation, the hole diameter of boring formation under drill bit is not less than 40mm, uses the chemical sizwe transfer pump of Double-liquid mud-injection pump to determine that the chemical sizwe of proportioning injects in hole under drill bit while boring; And the bore operation in ground layer drainage construction step has carried out stratum draining by the side of working face successively to opposite side.
Stratum consolidation slip casting is carried out after completing stratum draining, need when stratum consolidation slip casting again underground drill rig to be moved to the hole place completing stratum draining, drill bit is pierced in hole again, uses when drill bit arrives bottom hole the filling perforation of Double-liquid mud-injection pump reinforcing slurry transfer pump filling perforation to be reinforced slurry injection and completed in the hole of stratum draining; Stratum consolidation slip casting process is carried out to central area by working face periphery.Stratum consolidation slip casting process slip casting termination upwards promotes by bottom hole, in slip casting process, drilling rod is carried on marginal not slurry limit, strict control lifting amplitude, often step is 0.3 ~ 0.4m, at the uniform velocity pumpback, notes grouting parameter change, hoisting velocity according to flow rate of grouting and grouting amount and the adjustment of slip casting penetration radius, need proceed shadoof after grouting amount or grouting pressure reach design load.
The process need of slip casting strictly controls grouting pressure, pays close attention to grouting amount simultaneously, when rising instantaneously when pressure or overflow starch from hole wall, section sand layer, should stop slip casting immediately, take the adjustment measure such as grouting parameter or displacement slip casting again after ascertaining the reason.
Embodiment 1 completes entirely layer drainage construction process laggard perform hole hole consolidation grouting, and effectively can get rid of the moisture contained by stratum in whole process, reinforcing body compressive strength is higher, impervious effective.
embodiment 2
Stratum drainage construction is carried out after determining proportioning, reuse underground drill rig and carry out bore operation, the hole diameter of boring formation under drill bit is not less than 40mm, uses the chemical sizwe transfer pump of Double-liquid mud-injection pump to determine that the chemical sizwe of proportioning injects in hole under drill bit while boring; The filling perforation reinforcing slurry starting Double-liquid mud-injection pump when drill bit upwards promotes starts slip casting, strict control lifting amplitude, often step is 0.3 ~ 0.4m, at the uniform velocity pumpback, note grouting parameter change, hoisting velocity according to flow rate of grouting and grouting amount and the adjustment of slip casting penetration radius, need proceed shadoof after grouting amount or grouting pressure reach design load.
The process need of slip casting strictly controls grouting pressure, pays close attention to grouting amount simultaneously, when rising instantaneously when pressure or overflow starch from hole wall, section sand layer, should stop slip casting immediately, take the adjustment measure such as grouting parameter or displacement slip casting again after ascertaining the reason.
In whole process, underground drill rig bore operation is carried out to central area by working face periphery, and needs to detect stratum geological condition in the process of bore operation, and the proportioning of slurry is reinforced in base area layer parameter adjustment chemical sizwe and filling perforation.
Carry out hole consolidation grouting when embodiment 2 promotes drilling rod after carrying out ground layer drainage construction process and completing, whole process can once complete, and effectively improves efficiency of construction.
Embodiments of the invention 1 and embodiment 2 all first carry out soil body draining with water glass solution I and phosphoric acid solution, improve the impermeability of the soil body, soil solidifying is carried out again with water glass solution II and cement paste, change former physical properties of soil and improve the compressive strength of the soil body and impervious effect, finally make weak soil layer (especially chiltern, gravelly clay and layer of sand) become impervious high, compressive strength is high and stability the is high soil body, thus meet design requirement and reach soil stabilization.
The foregoing is only better embodiment of the present invention, the present invention is not limited to above-mentioned embodiment, local minor modifications may be there is in implementation process, if do not depart from the spirit and scope of the present invention to various change of the present invention or modification, and belonging within claim of the present invention and equivalent technologies scope, then the present invention is also intended to comprise these change and modification.