Summary of the invention
In order to solve above technical problem; the invention provides and carrying out the job practices that agitation pile is reinforced around the built shield tunnel; agitation pile around the tunnel is divided into different types; the water/binder ratio of the agitation pile by controlling variant type and the sinking and the hoisting velocity of stirring-head; thereby be reduced in when carrying out mixing pile construction the influence that shield tunnel is on every side caused; and to around shield tunnel form protection, reduce the protuberance amount of shield tunnel.
Of the present inventionly around built shield tunnel, carrying out the job practices that agitation pile is reinforced, the agitation pile of reinforcing around the built shield tunnel is divided into the isolation agitation pile of both sides, tunnel, the reinforcing agitation pile of tunnel upper and the reinforcing agitation pile of isolating the agitation pile outside, and this method mainly may further comprise the steps:
Carry out stake position setting-out in each position that need beat agitation pile;
Excavate groove in each position, position, make at least one mud pit on construction ground;
With the agitation pile pile-forming machine perching, and the stake machine carried out rectify perpendicular;
On the drilling rod of stake machine, do the long control mark of stake;
Sink and promote the mixing pile machine drilling rod, carry out slip casting simultaneously;
It is characterized in that: both sides, described tunnel are provided with at least two rows and isolate agitation pile, and adopt the jumping play to isolate the piling of agitation pile; Adopt the jumping play that the reinforcing agitation pile of tunnel upper is driven piles; Utilize the method for piling continuously that the reinforcing agitation pile in the isolation pile outside is driven piles.
The further improvement of this method is: described jumping play of driving piles used to the isolation agitation pile of both sides, tunnel adopts the mode of plaing a jumping two.
The further improvement of this method is: described jumping play of driving piles used to the reinforcing agitation pile of tunnel upper adopts the mode of plaing a jumping two.
The further improvement of this method is: during slip casting, the water/binder ratio of the cement grout of described isolation agitation pile is 1.5~1.8 in stake machine piling process.
The further improvement of this method is: during slip casting, the water/binder ratio that described tunnel upper stirs the cement grout of reinforcing stake is 1.2~1.4 in stake machine piling process.
The further improvement of this method is: in stake machine piling process during slip casting, the water/binder ratio of cement grout that described tunnel isolates the reinforcing agitation pile in the agitation pile outside is 1.4~1.6.
The further improvement of this method is: to the tunnel lateral septal when agitation pile is driven piles, the stirring-head of stake machine is whitewashed in the sinking process, and the stirring-head subsidence velocity is less than 0.4m/min; Do not whitewash during lifting, and the stirring-head hoisting velocity is less than 0.6m/min.
The further improvement of this method is: when the reinforcing stake of tunnel upper is driven piles, whitewash in the stirring-head sinking process of stake machine, do not whitewash during lifting; And the stirring-head subsidence velocity is less than 0.4m/min, and the stirring-head hoisting velocity is less than 0.6m/min.
The further improvement of this method is: when the reinforcing agitation pile of the tunnel being isolated the agitation pile outside is driven piles, whitewash in the stirring-head sinking process of stake machine, do not whitewash during lifting; And the stirring-head subsidence velocity is less than 0.4m/min, and the stirring-head hoisting velocity is less than 0.6m/min.
By above-described technical scheme; of the present inventionly around built shield tunnel, carrying out the job practices that agitation pile is reinforced; the isolation agitation pile that agitation pile around the tunnel is divided into the outside, tunnel; the reinforcing agitation pile of tunnel upper and three kinds of dissimilar agitation piles of reinforcing agitation pile of isolating the agitation pile outside; the water/binder ratio of the agitation pile by controlling variant type and the sinking and the hoisting velocity of stirring-head; thereby be reduced in when carrying out mixing pile construction the influence that shield tunnel is on every side caused; and to around shield tunnel form protection; reduce the protuberance amount of shield tunnel, and can make isolate agitation pile apart from the minimum distance of shield tunnel in 1 meter scope.
The specific embodiment
In conjunction with a specific embodiment the specific embodiment of the present invention is described in detail.Constructed by the built shield tunnel one, in order not influence this normal operation of built shield tunnel, protect this built shield tunnel, need carry out mixing pile construction around the built shield tunnel at this, around shield tunnel, form stabilization zone, with reference to figure 1, the stabilization zone 30 in the stabilization zone 20 of shield tunnel 10 both sides, stabilization zone 20 outsides and the stabilization zone (not shown) of shield tunnel 10 tops; And when carrying out mixing pile construction, in order to reduce the shield tunnel protuberance that mixing pile construction causes, reach the structural requirement of shield tunnel, guarantee the normal operation of shield tunnel, agitation pile in the stabilization zone around the built shield tunnel is divided three classes: nearly shield tunnel and be parallel to the isolation agitation pile that shield tunnel is provided with, and in this specific embodiment, isolation pile is 700mm apart from shield tunnel, in order to guarantee enough good isolation effect, isolation agitation pile that three rows are parallel to shield tunnel is set (certainly, also can be according to concrete construction needs, the isolation agitation pile of required row's number is set), the degree of depth of this isolation agitation pile will run through whole tunnel, and extend to the certain degree of depth in below, tunnel, the degree of depth of this extension is relevant with concrete soil layer, according to different soil layers, the degree of depth difference of this extension, and should the full hall reinforcing of isolation agitation pile form stabilization zone 20; The reinforcing agitation pile of shield tunnel top, the distance at the top of the distance from bottom shield tunnel of this reinforcing agitation pile is generally more than 1m, the height of this reinforcing agitation pile will be determined according to the requirement of different soil layer constructions and engineering, and should reinforce the full hall of agitation pile and reinforce the stabilization zone (not shown) that forms 10 tops, tunnel; And the reinforcing agitation pile in the isolation pile outside, the length of this reinforcing agitation pile generally is identical with the length of isolation agitation pile, and should the full hall reinforcing of reinforcing agitation pile form stabilization zone 30.
When carrying out mixing pile construction, the sequence of construction of three types agitation pile can be according to the demand of concrete engineering, select corresponding sequence of construction, we adopt the isolation agitation pile of first construction tunnel both sides in this specific embodiment, and then the reinforcing agitation pile in the reinforcing agitation pile of construction tunnel top and the isolation pile outside, adopting specification in this specific embodiment is the agitation pile of Ф 850, and the stake footpath is 850mm, and wherein the mixing pile construction step mainly comprises:
A) stake position setting-out:
Control point direct-axis line direction is extended to outside the construction area both sides five meters local and bury underground along axis direction with steel nail; Emit the stake position by site technology person according to design drawing and measurement control point, a stake bit plane deviation is not more than 5cm.
B) excavation groove and make mud pit:
Clean and tidy for the safety displacement that guarantees a machine and job site uses digging machine to excavate groove in advance on agitation pile stake position, in order to deposit the mud that cements out in the piling process, the about 1.2m of ditch groove width, dark 0.7~1m; Also need make a big mud pit in addition at the construction field (site), place in it, treat the dried slightly back outward transport of soil body mud in order to the soil body mud that will on each position, cement out in three mixing pile construction processes.
C) excavation guide groove:
According to bracing of foundation pit inner edge control line, adopt digging machine excavation guide groove, and remove underground obstacle, the surplus soil of excavation groove should in time be handled.
D) placement positioning shaped steel:
The vertical trench direction is placed two location shaped steel, and specification is 200mm * 200mm, is about 2.5m, places two location shaped steel specification 300mm * 300mm in the parallel groove direction again, is about 8~20m.
E) stake in place machine and carry out the rectify perpendicular of a machine:
Perform at the beam worker of carrying out above each step, with pile-forming machine perching; Pile-forming machine perching ground is not only smooth, solid, lays some 2m * 7m roadbed steel plate casees simultaneously under creeper tread; When pile-forming machine perching, leg oil pressure stent support can be guaranteed vertically construction firmly of a machine like this before and after it on the road headblock in addition.
Behind pile-forming machine perching, the stake machine is carried out rectify perpendicular: on the pile frame of stake machine, be welded with the iron ring that a radius is 5cm, hang a plummet, utilize transit to proofread and correct the drilling rod verticality, make plummet just in time by the iron ring center from the eminence of iron ring 10m.Must suitably regulate drilling rod before each piling construction, make plummet probably be positioned at the center of iron ring, promptly the drilling rod error of perpendicularity is controlled in 0.5%, can guarantee that like this each agitation pile is in vertical direction substantially.
F) the long control mark of stake:
Because the long variation of this engineering agitation pile stake is more, therefore before carrying out the agitation pile piling construction, the stake that all should determine this agitation pile is long, on stake machine drill bar, carry out respective markers according to the stake of this agitation pile is long, can control a machine like this and carry out agitation pile when piling, making that stake is long must not be less than designing pile length; When playing new stake,, wipe old mark, according to the long mark newly of on drilling rod, carrying out accordingly of new stake if during changing of stake long hair.
G) begin piling:
Behind the long mark of the good stake of drilling rod subscript, start a stake machine and drive piles, should put up before the construction and mix the slurry platform, all workmans are carried out the work of telling somebody what one's real intentions are of detailed construction technology; Begin piling, drilling rod sinks and promotes slip casting, stirring, lifting.To dissimilar agitation piles, volume used when it is driven piles is distinguished to some extent according to the difference of its type.
When the isolation agitation pile in the shield tunnel outside was driven piles, the volume that its whitewashing is adopted was 20% Portland cement, and the water/binder ratio scope of cement grout is 1.5~1.8, available in this embodiment 1.6 water/binder ratio; Whitewash in the stirring-head sinking process, and its subsidence velocity can adopt 0.25m/min in this embodiment less than 0.4m/min, do not whitewash during lifting, and its hoisting velocity can adopt 0.4m/min in this embodiment less than 0.6m/min.
When the reinforcing agitation pile above the shield tunnel was driven piles, the volume that its whitewashing is adopted was 20% Portland cement, and the water/binder ratio scope of cement grout is 1.2~1.4, available in this embodiment 1.3 water/binder ratio; Whitewash in the stirring-head sinking process, the stirring-head subsidence velocity can adopt 0.25m/min in this embodiment less than 0.4m/min, does not whitewash during lifting, and the stirring-head hoisting velocity can adopt 0.4m/min in this embodiment less than 0.6m/min.
For the reinforcing agitation pile that shield tunnel is isolated the agitation pile outside, its construction technology is identical substantially with the reinforcing agitation pile of shield tunnel top; But, two kinds of water/binder ratio differences of reinforcing the cement grout that agitation pile adopted, the water/binder ratio of the reinforcing agitation pile cement grout of shield tunnel top is prepared according to 1.2~1.4 scope, shield tunnel is isolated the water/binder ratio of the reinforcing agitation pile cement grout in the agitation pile outside and is prepared available in this embodiment 1.5 water/binder ratio according to 1.4~1.6 scope.
And when carrying out mixing pile construction, according to the mixing pile construction technological requirement, drilling rod all need inject cement grout when sinking and promote.In addition, drilling rod subsidence velocity and hoisting velocity will be carried out in strict accordance with the construction parameter table, require even, continuous injection to mix the cement grout that makes, and drilling rod promotes when finishing, and the design cement grout has all been annotated, and this moment, mixing pile construction finished.
For dissimilar agitation piles, its sequence of construction and bridging method difference: with reference to figure 2 is the isolation agitation pile in the shield tunnel outside and the sequence of construction and the bridging method figure of the reinforcing agitation pile above the shield tunnel.When the agitation pile of this two class is constructed, adopt the jumping play to construct, adopt in this embodiment and make a call to one and jump two mode (can certainly adopt different jumping play), each agitation pile is numbered according to different requirement of engineering, when the first round constructs to being numbered 3n+1 (n=0,1,2, agitation pile 3...) is driven piles, and takes turns when construction to being numbered 3n+2 (n=0 second, 1,2, agitation pile 3...) is driven piles, and overlaps with the agitation pile that is numbered 3n+1, carry out the third round construction then, to being numbered 3n+3 (n=0,1,2,3...) agitation pile carry out piling construction, it overlaps with the agitation pile that is numbered 3n+2; In this specific embodiment, at first construct and isolate agitation pile from the nearest row of shield tunnel, behind the isolation agitation pile of finishing first row, and then carry out second row and isolate the construction of agitation pile, and second row's isolation agitation pile will overlap with first row's isolation, construct then the 3rd row's isolation agitation pile, and the 3rd row's isolation agitation pile will overlap (simultaneously with reference to figure 1) with second row's isolation agitation pile; The sequence of construction of the reinforcing agitation pile of shield tunnel top and method are identical with this sequence of construction and method of isolating agitation pile; The above is a kind of sequence of construction method of comparison standard, certainly in concrete work progress, can determine to jump according to concrete construction environment and beat sequence of construction.
With reference to figure 3 is the sequence of construction and the bridging method schematic diagram of the reinforcing agitation pile in the isolation pile outside.Reinforcing agitation pile to the isolation pile outside, order by continuous construction is constructed, and each is reinforced between the agitation pile and overlaps (simultaneously with reference to figure 1) mutually, and on having constructed after the construction of an agitation pile, the engineering time of itself and next agitation pile can be determined according to the requirement of concrete engineering at interval, what adopt in this project is continuous construction, on having constructed one reinforce agitation pile after, can carry out next mixing pile construction with that; Reinforcing agitation pile between each row overlaps (simultaneously with reference to figure 1) mutually in addition.
With reference to figure 4 in the specific embodiment of the invention when finishing all mixing pile constructions, the testing result schematic diagram of the protuberance amount of shield tunnel and deflection at a time, its abscissa is represented the position coordinates of each test point, the m of its unit, ordinate is represented the protuberance amount of each test point, its unit is mm, is adopting job practices of the present invention to carry out in the work progress, has arranged several protuberance observation points and monitor in real time on the shield tunnel axis; In this concrete enforcement, finish to a last agitation pile since first mixing pile construction, last 3 months, from Fig. 4, can learn, point sometime after the construction of finishing all agitation piles, the total protuberance amount of actual shield tunnel is no more than 5mm, and deflection is no more than 1mm.Table 1 has provided since first mixing pile construction and has finished to a last agitation pile, lasted 3 months and after finishing two months of constructing in, the protuberance amount of shield tunnel every month, the data of being given from form can learn that the protuberance amount of the every month of shield tunnel also all is no more than 5mm, and the deflection of every month also all is no more than 1mm.And, according to protuberance variable quantity and builder's diary at construction period shield tunnel each monitoring location every day, can find the nearest local shield tunnel protuberance maximum in agitation pile position that distance has just been constructed, can swell the back and sink finishing near the agitation pile position of construction shield tunnel, adopt job practices construction of the present invention, vertical protuberance can take place or sink in shield tunnel, monitored data after finishing according to whole stabilization zone mixing pile construction, contrast finds that the shield tunnel protuberance amount that each odd-numbered day mixing pile construction causes is no more than 0.5mm, and deflection is no more than 0.36mm; This shows, according to each monitoring point monitoring result of every day, and after all mixing pile constructions finish, protuberance amount that shield tunnel is final and deflection all satisfy the structural requirement of built shield tunnel, guarantee the normal operation of shield tunnel, produce good effect.
Table 1
Survey period |
Y0 |
Y1 |
Y2 |
Y3 |
Y4 |
Y5 |
Y6 |
Y7 |
Y8 |
Y9 |
Y10 |
Y11 |
Y12 |
Y13 |
Y14 |
Y15 |
September |
0 00 |
0.00 |
0 02 |
0 09 |
0 18 |
0 20 |
0 19 |
0 20 |
0.19 |
0.21 |
0 26 |
0.24 |
0 16 |
0.09 |
0 05 |
0 01 |
October |
0 00 |
0 01 |
0 09 |
0.17 |
0 31 |
0.34 |
0.37 |
0.43 |
0 46 |
0 58 |
0 69 |
0 56 |
0 51 |
0 45 |
0 43 |
0 42 |
November |
0 00 |
0 11 |
0 31 |
0 43 |
0 63 |
0 64 |
0.64 |
0 62 |
0 79 |
1 09 |
1.50 |
1 68 |
1 83 |
1 96 |
2.12 |
2.31 |
December |
0 00 |
0 29 |
0 73 |
0 99 |
1 38 |
1 35 |
1 24 |
1 03 |
1.15 |
1 47 |
2 14 |
2.38 |
2 73 |
2 82 |
3 04 |
3.48 |
01 month |
0.00 |
0.75 |
1.68 |
2.02 |
2.25 |
1.47 |
0 62 |
-0 31 |
-0.57 |
-0.51 |
0 08 |
0 22 |
0 56 |
0.69 |
0.89 |
1.57 |
Survey period |
Y16 |
Y17 |
Y18 |
Y19 |
Y20 |
Y21 |
Y22 |
Y23 |
Y24 |
Y25 |
Y26 |
Y27 |
Y28 |
Y29 |
Y30 |
Y31 |
September |
-0 01 |
-0.11 |
-0.10 |
-0 13 |
-0 13 |
-0 18 |
-0 25 |
-0.30 |
-0.29 |
-0.29 |
-0.28 |
-0 27 |
-0 29 |
-0.22 |
-0.27 |
-0.29 |
October |
0 46 |
0 40 |
0.58 |
0 54 |
0.54 |
0 46 |
0 24 |
0.15 |
0 12 |
0.08 |
0.00 |
-0 10 |
-0.21 |
-0.19 |
-0 29 |
-0.37 |
November |
2.45 |
2.37 |
2.69 |
2.89 |
3 19 |
3 39 |
3.21 |
3 10 |
2 99 |
2.83 |
2 44 |
2.02 |
1.42 |
1.09 |
0.81 |
0.56 |
December |
3 83 |
3 56 |
3 85 |
3 90 |
4.04 |
4.13 |
3 90 |
4 00 |
3.90 |
3.57 |
2.84 |
2 09 |
1.37 |
1.20 |
0 49 |
0.05 |
01 month |
2.23 |
2 02 |
2.55 |
2.81 |
3 10 |
3 43 |
3.49 |
3.84 |
3.86 |
3.52 |
2.67 |
1.73 |
0.94 |
0.64 |
-0.28 |
-0.73 |
Survey period |
Y31 |
Y32 |
Y33 |
Y34 |
Y35 |
Y36 |
Y37 |
Y38 |
Y39 |
Y40 |
Y41 |
Y42 |
Y43 |
Y44 |
Y45 |
|
September |
-0.29 |
-0.28 |
-0.24 |
-0.19 |
-0.18 |
-0.17 |
-0.18 |
-0.16 |
-0.13 |
-0.05 |
-0.03 |
-0.01 |
0.04 |
0.05 |
0.00 |
|
October |
-0.37 |
-0.40 |
-0.39 |
-0.37 |
-0.41 |
-0.41 |
-0.38 |
-0.42 |
-0.34 |
-0.22 |
-0.15 |
-0.11 |
0.04 |
0.04 |
0.00 |
|
November |
0.56 |
0.35 |
0.16 |
0.11 |
-0.04 |
-0.13 |
-0.11 |
-0.19 |
-0.14 |
0.00 |
0.03 |
0.05 |
0.21 |
0.16 |
0.00 |
|
December |
0.05 |
0.04 |
0.22 |
0.51 |
0.61 |
0.45 |
0.26 |
0.02 |
-0.04 |
0.12 |
0.12 |
0.22 |
0.45 |
0.33 |
0.00 |
|
01 month |
-0.73 |
-0.63 |
-0.32 |
-0.05 |
0.06 |
0.03 |
-0.29 |
-0.52 |
-0.44 |
-0.10 |
-0.15 |
0.06 |
0.45 |
0.34 |
0.00 |
|
Be understandable that the detailed description of the foregoing description is in order to set forth and explain principle of the present invention rather than to the qualification of protection scope of the present invention.Under the prerequisite that does not break away from purport of the present invention, one of ordinary skill in the art can be made modification by the understanding to the principle of being instructed of technique scheme on these embodiment bases, changes and changes.Therefore protection scope of the present invention by appended claim with and be equal to and limit.