Technical background
At present, the weak soil such as barged-in fill, dredging silt stockyard, the silt of river lakebed, pond or other discarded heap loadings that exist without crust layer is often run in Process of Engineering Construction, as alkaline residue etc.In order to meet requirement for bearing capacity, modal processing mode is the draining of shallow-layer vacuum preloading or cushion.
Artificial plate is first adopted because plant equipment cannot enter during the process of shallow-layer vacuum preloading, first on barged-in fill silt stockyard, lay geo-grid and geotextiles, then manually carefully plastic draining board is inserted in mud as much as possible, manually arrange chimney filter, diaphragm seal etc. again, carry out the vacuum preloading without sand cushion, the time vacuumized needs three months or more, removes after namely chimney filter filter membrane etc. completes the process of shallow-layer vacuum preloading and spreads one deck sandstone sand-gravel cushion.The shallow-layer vacuum preloading processing mode processing time is long, and bearing power increase is limited, in addition due to the inhomogeneities of topsoil each point intensity after vacuum preloading process, also causes the danger that construction machinery is toppled over.Another kind of employing cushion, needs a large amount of sand-gravel cushions in processing procedure.During for light fill roadbed section or more shallow soft soil roadbed section, to satisfy the need rheobasic requirement to meet road surface, relatively more conventional method is cushion.In recent years, due to a large amount of exploitations of mountain stone, cause the in short supply of resource, material cost is high; Cause the natural calamity of landslide, mud-rock flow etc. simultaneously.And the cost of transportation of material is also higher, thus cause the cost of this kind of processing method higher.
In order to solve above Problems existing, be a kind of new method for processing foundation to the process of barged-in fill sludge solidification, the method utilizes mixing plant that curing compound and in-situ soil are cured process.Two kinds are solidified with at present for in-situ soil, a kind of is if application number is for as described in the patent of 200810056749.2, first configure slurries, then slurries are transported in the mixing plant of job site, and then inject in-situ soil by mixing plant, this construction method land occupation resource, and the transport of long distance can cause cost to raise.Secondly this kind of method be suitable for curing compound be cured process in form of slurry and the initial setting time long, for inapplicable this kind of processing method of the air-setting materials such as lime, and must matching while using put during the hydraulic material uses such as cement, overlong time causes curing compound to lose efficacy, cause solidification process not rest, otherwise curing compound need reconfigure.Given this, solidifying Problems existing on the spot at present to solve, a kind of method of in-situ soil being carried out to original place solidification process need be applied for, form method for processing foundation more effectively and rapidly.
Another kind utilizes curing apparatus on the spot that curing compound and in-situ soil are carried out mix, the traditional curing apparatus of domestic contrast is digging machine or road-mixed machine, publication number is the patent of CN102672656A, it discloses a kind of mixing plant, but its limitation due to structure design causes disposable process finite thickness, efficiency of construction is caused to reduce, and because do not arrange special atomization mechanism, so easily cause dust when curing compound is sprayed in top layer solidification.
Given this, also need to provide a kind of mixing plant that can overcome existing mixing plant existing defects.
application content
The application's object is to solve current Problems existing, a kind of method and the mixing plant that in-situ soil are carried out to original place solidification process are proposed, mixing plant is utilized to carry out in-situ solidifying process to top layer weak soil, quick formation has the method for processing foundation of certain surface bearing capacity, be specially adapted to the grounds such as process barged-in fill, dredging silt stockyard, the silt of river lakebed, soft superficial strata, process range can reach 0.5-3m, the method for processing foundation be a kind of economical, construction is flexible, can saved material and the energy.
In order to realize above-mentioned technical purpose, the application is achieved through the following technical solutions:
In-situ soil is carried out to a method for original place solidification process, comprises the following steps:
Step one, carries out draining and leveling process to in-situ soil surface;
Step 2, carries out block division to the in-situ soil processed through step one, according to process thickness, determines the hardener dose that every block block needs;
Step 3, adopts mixing plant to stir pretreatment in-situ soil, is evenly ejected into by curing compound in the in-situ soil carrying out stirring simultaneously;
Step 4, flattens the soil body after step 3 process, precompressed, and after stirring, after soil to be solidified reaches some strength, carry out precompressed to solidified earth, the pressure of precompressed controls between 50-400kPa.
When described step 3 situ soil pores ratio is less than 0.8-1.0, pine is adopted to turn over the mode of multi-shell curing, concrete grammar has two kinds: a kind of for first being undertaken tentatively stirring solidifying and stirring solidified earth being pushed into untreated section by mixing plant and in-situ soil in the region divided, and then divides three layers to stir tentatively stirring solidified earth again and compacting again; The second digs a stirring space at untreated section digging machine, and the degree of depth is treating depth, and then repeatedly stir from shoveling backfill, slowly forward stirs, and till the border of fixed bed, finally fills and leads up with digging machine.
When described step 3 situ soil pores ratio is greater than 1.0-1.5, adopt the mode stirring solidification vertically, mixing plant is direct insertion to be stirred in-situ soil, mixing plant forward runs and deeply stirs and spray curing compound gradually, until reach solidification design bottom, then mixing plant inverted running slowly promotes and stirs and spray curing compound, and stir the speed promoted or decline and control at 10-20s/m, the material spray speed of curing compound controls at 40-70kg/min.
The thickness carrying out stir process to in-situ soil in described step 3 is 0.5-3m.
Following three kinds are had to the mode that solidified earth carries out precompressed in described step 4:
1) walking machine is adopted to carry out precompressed to the soil body after stirring after laying steel plate or plank;
2) sandstone recycled or mount or water tank is adopted to carry out precompressed to the soil body after stirring;
3) fill material met design requirement is adopted to carry out precompressed to the soil body after stirring.
When carrying out block division in described step 2, the lap width after blockette solidification between each block is at least 5cm, after each block solidification processes, adopts mixing plant that the top layer soil body overlapped between each block is again stirred, solidified.
A kind of mixing plant, comprise mixing arm, mixing arm two bottom sides has intilted two inclined-planes, and each inclined-plane is respectively arranged with at least one mixing roller bearing, and mixing roller bearing is driven by driving arrangement and rotates, and mixing roller bearing is frustroconical; Described mixing roller bearing is distributed with blade mechanisms; Described mixing arm inside is provided with the curing compound conveying pipeline of extension type.
Described blade mechanisms is that one-way spiral type is distributed on mixing roller bearing.
Described blade mechanisms comprises the fixed head that is arranged on mixing roller bearing and is arranged at two orthogonal blades one on fixed head and blade two.
The end of described curing compound conveying pipeline is provided with atomization mechanism.
The application adopts technique scheme to have following technique effect:
Described in the application to in-situ soil carry out original place solidification process method be construct in original place, avoid in prior art the problem that barged-in fill and solidified earth can cause cost to raise in transport; This method short construction period, ground is soon base molded, substantially reduces construction period, thus has saved the time and through costly.And the foundation structure intensity that this method is formed is high, the vane-shear strength formed through final precompressed can reach 300kPa.
Mixing plant described in the application can process range wider, the weak soil under different water cut can be processed, when moisture content is low, slurry curing compound can be adopted to process, during moisture content height, can adopting slurries that pulvis curing compound also can be adopted to process, when the design of atomization mechanism is exactly to make pulvis shape curing compound spray, reducing dust pollution.Mixing roller bearing is designed to the frictional resistance that can reduce in frustroconical in whipping process and between the soil body, effectively reduces the proportion of goods damageds of mixing plant.
detailed description of the invention:
As shown in Figure 1, a kind of mixing plant described in the application, comprises mixing arm 1, mixing arm 1 two bottom sides has intilted two inclined-planes, each inclined-plane is respectively arranged with at least one mixing roller bearing 2, and mixing roller bearing 2 is driven by driving arrangement and rotates, and mixing roller bearing 2 is in frustroconical; Described mixing roller bearing 2 is distributed with blade mechanisms 3; Described mixing arm 1 inside is provided with the curing compound conveying pipeline 4 of extension type.
Preferably, the end of described curing compound conveying pipeline 4 is provided with atomization mechanism 5.When mixing plant process surface location adopts curing compound to be pulvis, in order to avoid environment pollution, in good time beginning atomization mechanism 5.When atomization mechanism 5 uses, will not add in atomization mechanism 5 with curing compound generation chemical reaction liquid, the content of described liquid be generally about the 4-8% of solid.
Mixing roller bearing 2 is designed to be the frictional resistance in order to reduce in whipping process and between the soil body in frustroconical.Curing compound conveying pipeline 4 is designed to extension type, can reduce the pollution of curing compound when surface is stirred.
Preferably, blade mechanisms 3 is distributed on mixing roller bearing 2 in one-way spiral type, the soil body that mixing roller bearing 2 rotates after a week in slewing area all can contact and disturbance, can stir without blind spot solid continuously, improve the uniformity of mixture after stirring, and disposable treating depth reaches 3m.
As shown in Figure 2, described blade mechanisms 3 comprises the fixed head that is arranged on mixing roller bearing 2 and is arranged at two orthogonal blades 1 on fixed head and blade 2 32.Blade 2 32 is to destroy foundation soil structure, blade 1 is for stirring, in use procedure, blade 2 32 pairs of in-situ soil are utilized to cut, the in-situ soil of blade 1 and the 2 pairs of destroyeds of mixing roller bearing is utilized to stir afterwards, blade mechanisms 3 helically type is distributed on mixing roller bearing 2, and soil body solid can be realized to stir.
As shown in Figure 5, during use, mixing plant described in the application is installed on the front end of digging machine.
The application is for the soft of pending soil property or curing mode that hard selection is different and precompressed mode, and below for the softer barged-in fill of soil property or silt stockyard, and the processing method of the harder roadbed dam construction of soil property elaborates:
Embodiment 1
As shown in Figure 3, adopt mixing plant to carry out the method for original place solidification process to barged-in fill or silt stockyard, comprise the following steps:
Step one, carries out draining and leveling process to in-situ soil surface; When there is ponding on in-situ soil surface, surface drainage and leveling place first need be carried out;
Step 2, carries out block division to the in-situ soil processed through step one, according to process thickness, determines the hardener dose that every block block needs; When carrying out block division, the lap width after blockette solidification between each block is at least 10cm, after each block solidification processes, adopts mixing plant that the top layer soil body overlapped between each block is again stirred, solidified;
Step 3, adopt the mode stirring solidification vertically, mixing plant is direct insertion to be stirred in-situ soil, mixing roller bearing 2 forward in mixing plant runs, deeply stir and spray curing compound gradually, until reach cured layer design bottom, then mixing roller bearing 2 inverted running and slowly promote and stir and spray curing compound, stirring the speed promoted or decline controls at 10-20s/m, and the material spray speed of curing compound controls at 40-70kg/min;
Step 4, leveling, precompressed, after stirring, after soil to be solidified reaches some strength, carry out precompressed to solidified earth, the pressure of precompressed controls between 50-400kPa; Because the mode that solidification process adopts solidification limit, limit to advance is carried out, for the cured layer formed before, need for follow-up continuation solidification lays the foundation, so, when solidified earth strength ratio is when cured lower, after paving one deck steel plate can be adopted, with walking arrangement, precompressed is carried out to the soil body after stirring; When solidified earth intensity is higher, the sand bag that employing recycles or water tank carry out precompressed to the soil body after stirring.
Embodiment 2
As shown in Figure 4, adopt mixing plant to carry out the method for original place solidification process to roadbed dam construction, comprise the following steps:
Mixing plant carries out original position to the in-situ soil in roadbed dam construction and stirs the method for processing foundation solidifying to form large area plate body, and the method comprises the following steps:
Step one, carries out draining and leveling process to in-situ soil surface; When there is ponding on in-situ soil surface, surface drainage and leveling place first need be carried out;
Step 2, carries out block division to the in-situ soil processed through step one, according to process thickness, determines the hardener dose that every block block needs; When carrying out block division, the lap width after blockette solidification between each block is at least 10cm, after each block solidification processes, adopts mixing plant that the top layer soil body overlapped between each block is again stirred, solidified;
Step 3, when in-situ soil strength ratio is lower, the paddling process of stirring vertically in embodiment one is adopted to construct, pine is adopted to turn over the mode of multi-shell curing when soil property is harder, because if adopt the mode required drive stirring solidification vertically larger, time more serious to the wearing and tearing of blade, therefore adopt pine to turn over the mode of multi-shell curing, specific implementation method has two kinds: a kind of for first being undertaken tentatively stirring solidifying and stirring solidified earth being pushed into untreated section by mixing plant and in-situ soil in the region divided, then three layers are divided to stir tentatively stirring solidified earth again and compacting again, the second digs a stirring space at untreated section digging machine, and the degree of depth is treating depth, and then repeatedly stir from shoveling backfill, slowly forward stirs, and till the border of fixed bed, finally fills and leads up with digging machine.
Step 4, leveling, precompressed, stir complete, after soil to be solidified reaches some strength, carry out precompressed at once with the design filler of 50-400kPa;
During as processed according to pulvis shape curing compound, when mixing plant stretches out the soil body, atomization mechanism 5 can be opened, spraying special material, suppress dust.
Embodiment 3
Mixing plant is adopted to carry out original place solidification process to alkaline residue field, the alkaline residue Slag bearing capacity solidify to form controls at 80kPa, process thickness is 1.4m, and to solidify the method processed identical with adopting mixing plant to carry out original place to barged-in fill or silt stockyard described in embodiment 1 for construction method.
Also a kind of curing compound containing GBFS can be used to be cured process, and the composition of described curing compound comprises: GGBS2%-15%; Cement 0%-15%; Flyash 0%-15%; Yellow ground 0%-15% and other, described percentage is all weight percentage,
Wherein, GGBS need meet: specific area >=300 ㎡/kg, 7 days activity index >=50%; Flyash need meet: length of side 0.045mm square hole screen screen over-size≤50%; Loss on ignition≤20%; Yellow ground need meet: particle diameter≤1.75mm.
The Main Function of each composition:
The effect of GGBS: hydration produces gum material.Increase intergranular cementation.
The effect of cement: generate aquation gum material through hydration reaction, increase intergranular cementation.
The effect of flyash: hydration reaction occurs, generates the water-fast stable crystallines such as hydrated calcium silicate, drated calcium aluminate and hydrated calcium ferrite, hardens gradually thus plays reinforcement effect to alkaline residue.
The effect of yellow ground: the grating changing alkaline residue, improves degree of compaction.
When alkaline residue field, thickness is large, when the stockyard formed is to settlement request height, can combinationally use in conjunction with cured layer and agitation pile or preformed pile, the topsoil formed solidifies on the spot and the original position soil layer that the foundation structure carried comprises the cured layer on top, the bearing stratum of bottom and be clipped between cured layer and bearing stratum is combined in stake, vertically plugs some foundation piles in described original position soil layer.
Mixing plant described in the application can process range wider, the weak soil under different water cut can be processed, when moisture content is lower than 50% percentage by weight, slurry curing compound can be adopted to process, when moisture content is higher than 50% percentage by weight, can adopt slurries that pulvis curing compound also can be adopted to process, the visible denomination of invention of system utilizing pulvis curing compound to carry out processing is the patent application of " a kind of feeder apparatus realizing pulvis automatic ration and control ".
The method that employing mixing plant described in the application carries out original place solidification process when processing the high weak soil of clay content percentage, can the dry sand of admixture 2%-5% percentage by weight as medium, change the grain composition of the original position soil body itself, make stirring evenly.
The application's construction method described above is not limited to the mixing plant used described in the application, can also use the mixing plant existed in prior art.