A kind of shield tunnel simultaneous grouting slurry that is applicable to soft following hard compound stratum
Technical field
The invention discloses a kind of shield tunnel simultaneous grouting slurry, particularly a kind of shield tunnel simultaneous grouting slurry that is applicable to soft following hard compound stratum belongs to the shield tunnel project technical field.
Background technology
Along with developing rapidly of urban track traffic field, driven the application of metro shield worker law technology.Because the excavation of shield engine driving can produce disturbance to the stratum inevitably; Simultaneously owing to have structure void between excavation face and lining segment; Make the face of land along the line, tunnel produce certain sedimentation; For last soft hard compound stratum down, the sedimentation and deformation on the face of land is difficult to control more, if do not adopt an effective measure ground settlement is not controlled especially; In case take place to show sedimentation significantly, will produce very big risk.Therefore, in the shield engine driving, adopt synchronous grouting control ground settlement very important in allowed band.
At present, used simultaneous grouting slurry is divided into single slurries and two kinds in two slurries in the subterranean tunnel shielded construction.Single slurries mainly are made up of cement, flyash, sand, water etc.Two slurries are made up of A liquid and B liquid, and the mortar that A liquid is made up of cement, wilkinite, stability material and water, B liquid are water glass.Because single slurries easy construction, management are easily, thereby existing shield tunnel simultaneous grouting slurry adopts single slurries more and seldom adopts two slurries.
The typical weight proportion of each raw material is a cement in existing single slurries: flyash: sand: water=1: 3.6: 2: 0.2: 2.43; These list slurries are longer time of coagulation, can not fixed timely and effectively section of jurisdiction, fill structure void, after the shield tail is hauled out in the section of jurisdiction; Can not effectively control ground settlement; Ground settlement is at 10~15mm, and cement and bentonite content are higher, and cost is higher.
The typical percentage volume of each raw material is in existing two slurries: cement 21.23%, wilkinite 2.5%, stability material 0.34%, water 67.73%, water glass 8.2%.Though this pair slurries early strength is higher, the flowability better; But in construction process, be easy to generate slurries segregation, plugging phenomenon, directly influence coagulation result and the construction speed of slurries in the stratum, not only delayed the engineering time; Also because of the discharging of discarded slurries, newly mixing etc. has increased construction cost.And this proportioning simultaneous grouting slurry is used for the soft shielded construction of hard compound stratum down, and the ground settlement scope is at 10~15mm, and ground settlement is bigger, admittedly be inappropriate for the soft shielded construction of hard compound stratum down.
Summary of the invention
The object of the present invention is to provide a kind of soft shield tunnel simultaneous grouting slurry of hard compound stratum down that is applicable to; To guarantee that the slurries presetting period adapts to shield driving construction and remote requirement of carrying; Reduce plugging and slurries segregation; Can fill structure void timely and effectively, reduce ground settlement.
In order to realize the foregoing invention purpose, the inventor provides following technical scheme through TE:
A kind of shield tunnel simultaneous grouting slurry that is applicable to soft following hard compound stratum; Form by mortar and water glass; Said mortar is made up of cement, sand, flyash, wilkinite and water; It is characterized in that: the weight ratio of said mortar and water glass is: water glass: mortar=1: 4, the weight ratio of each raw material is in the said mortar: cement: sand: flyash: wilkinite: water=1: 4.8~5.71: 2.93~3.31: 0.20~0.27: 3.13~3.30.Said slurry consistency is 120mm, can suitably adjust according to on-the-spot water-containing rate during actual the use.
Cement: sand: flyash: wilkinite: water=1: 4.8: 2.93: 0.25: 3.24.
Said cement can be ordinary Portland cement or composite Portland cement.
Shield tunnel simultaneous grouting slurry of the present invention is made up of mortar and water glass; With sand, flyash and cement is the slurry consolidation strength materials, and cement also be hydraulic cementing materials simultaneously, in order to adjusting slurries time of coagulation; Wilkinite is in order to increase the cementability of slurries; Slow down the separation of slurry material, water glass is the soluble alkali metal silicate that is formed by alkalimetal oxide and silica bound, and its staple is Na
2SiO
3,, work to regulate setting time as solidifying agent.
Compared with prior art, the present invention has following beneficial effect: the synchronous slurries of shield tunnel of the present invention, its proportioning confirms that through TE is final slurry consistency is good, is difficult for segregation, can effectively prevent the phenomenon of slurries segregation, obstruction Grouting Pipe.Slurry fluidity is good, can fill the peripheral structure void in excavation face and section of jurisdiction timely and effectively, can solidify at short notice, early reaches original soil intensity, makes it play the control ground settlement, constraint section of jurisdiction displacement, the formation first road water-stop curtain.Adopt slurries of the present invention to be used for the soft construction of hard compound stratum down, ground settlement is controlled in 5~7mm.
Embodiment
Below in conjunction with embodiment the present invention is made further detailed description.But should this be interpreted as that the scope of the above-mentioned theme of the present invention only limits to following embodiment, allly all belong to scope of the present invention based on the technology that content of the present invention realized.The simultaneous grouting slurry that the following example is cited; Form by mortar and water glass; Wherein the part by weight of mortar and water glass is: water glass: mortar=1: 4; Said mortar is made up of cement, sand, flyash, wilkinite and water, and slurry consistency is 120mm, can suitably adjust according to on-the-spot water-containing rate during actual the use.
Embodiment 1
In the slurries that present embodiment is enumerated, the consumption of each raw material is (a unit: kg/m in the mortar
3) be: cement 150, sand 720, flyash 440, wilkinite 37, water 470.
The slurries of this proportioning are used for Guangzhou metro section constructing tunnel; This construction segment mileage scope left side line is ZDK22+392.964~ZDK22+856.392; Left side line total length 474.928m, right line is YDK22+202.194~YDK22+856.392, length is 654.473m; Two line length overall 1129.401m, distance between centers of tracks is 5.0~23.4m.This section geology is mainly silty clay stratum, plastic shape residual soil, little waste mantle.In shield driving; Through the force feed effect of grouting pump, slurry filling is gone among the section of jurisdiction ring external series gap of shield tail, reach filling section of jurisdiction ring outer void, fixedly position, section of jurisdiction, minimizing land subsidence, serve as the purpose of encircling the outer first road water-proof wire; And guarantee the stability in early stage and later stage of pipe-plate lining; Reduced the distortion on ground when the shield structure advances effectively, the ground settlement of this section constructing tunnel is controlled in the 5mm, has protected surrounding enviroment effectively.
Embodiment 2
In the slurries that present embodiment is enumerated, the consumption of each raw material is (a unit: kg/m in the mortar
3) be: cement 147, sand 840, flyash 486, wilkinite 40, water 486.
The slurries of this proportioning are used for Guangzhou metro section constructing tunnel, the right line YDK27+088.00~YDK28+169.127 of this construction segment mileage scope, long 1081.127m; Left side line ZDK27+088~ZDK28+169.936, long 1078.090m, two line length overall 2159.217m.When the shield structure tunnels in this interval, do not having the soil cave location of dissolving, using this simultaneous grouting slurry proportioning, ground settlement all is controlled in the 7mm.