CN104762950A - Road mined-out area treatment method - Google Patents
Road mined-out area treatment method Download PDFInfo
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- CN104762950A CN104762950A CN201510159644.XA CN201510159644A CN104762950A CN 104762950 A CN104762950 A CN 104762950A CN 201510159644 A CN201510159644 A CN 201510159644A CN 104762950 A CN104762950 A CN 104762950A
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Abstract
The invention relates to a road mined-out area treatment method, belonging to the technical field of road geological disasters and in particular relating to a method for treating a big empty hole and a water-filled mined-out area under a road. The method comprises the steps: (1) positioning and pore-forming; (2) judging the type of a grouting hole and grouting an orifice pipe; (3) grouting similar concrete; (4) stopping grouting of similar concrete; (5) pressure grouting; (6) completion of grouting. The invention is particularly applicable to a road mined-out area with higher residual deformation of covered rock or with a large amount of filled water after underground mining.
Description
Technical field
The present invention relates to a kind of highway goaf harnessing method, belong to Highway Geological Disaster technical field, be related specifically to highway and underlie the administering method of macroscopic-void and full-water goaf.
Background technology
In the improvement in goaf, often run into the situation that cavity, goaf is larger, adopt traditional grouting treatment method just to seem helpless.In usual design, curtain pitch of holes is excessive, does not have the effect of curtain, general slurries are excessively rare, when slurries are noted by injection body position, slurries dispersal direction to all the winds spreads in theory, when cavity is larger, slurries can be preferential to potential barrier is dynamic lower as flowing water, if slurries can not get the stop of curtain, can to all the winds flow, in this case always, it is very difficult for wanting to fill a hole, and the goaf of therefore existing slurry material to macroscopic-void is inapplicable.
Summary of the invention
The object of this invention is to provide a set of goaf harnessing technique, this technique is improved from aspects such as perforate requirement, injecting paste material, termination slip casting conditions, can be good at the deficiency solving traditional grouting process, the input of human and material resources can greatly be reduced, increase economic efficiency.
The present invention adopts following technical scheme to realize:
A kind of highway goaf harnessing method, comprises the steps:
(1) fixed point pore-forming
Adopt total powerstation according to design boring coordinate carry out field survey setting-out, boring deviations of actual position be no more than 0.5m, because of landform, atural object impact can not setting-out time, the bore position deviation distance after adjustment is not more than 3m;
(2) differentiate grout hole type and build orifice tube
Determining grout hole classification according to creeping into information summary differentiation, when occurring falling that brill is greater than the situation of 0.5m in drilling process, determining that this hole is for filling with class concrete hole; Injected hole is defined as when occurring falling that brill is less than the situation of 0.5m in drilling process;
Building orifice tube adopts sleeve pipe as filling concrete pipe and Grouting Pipe, and build with plain-water slurry liquid, port, ground welded flange fills with concrete and grouting equipment in order to link;
(3) class concrete is poured into
Preparation class concrete mixing plant is with reference to " design of common concrete proportioning code " JGJ55-2011, and the class concrete of the suitable pumping of preparation carries out pumping pressure bashing cavity; During construction, pumping class concrete body of paste is filled cavity, goaf and water-filling cavity is carried out to extrusion drainage displacement filling;
(4) perfusion class concrete is stopped
In the latter stage of perfusion class concrete, pump pressure can raise gradually, when orifice tube place pressure limiting valve is opened automatically, stops perfusion class concrete;
(5) slip casing by pressure
After perfusion class concrete terminates, to being judged to be that slip casing by pressure construction is carried out in the boring of injected hole;
Sequence of construction: by the incline direction in goaf, the injected hole near the injected hole of gob floor absolute altitude lower position of first constructing and structure, then construct to center deployment along inclined direction from low to high, by edge;
Slip casing by pressure: slip casting adopts concentration of slurry first rare rear thick method; Thin pulp groundwater increment is 50% of single hole grouting amount;
If when there is a large amount of running pulp of surface cracks in slip casting process, adopt batch (-type) slip casting or reduce grouting pressure, stoping slurries to run off in a large number from ground;
(6) slip casting is stopped
In the slip casting latter stage of injected hole, pump pressure raises gradually, and when pump amount is less than 70L/min, according to structure type and goaf feature, aperture pressure stability, at 1.0 ~ 3.0MPa, when continuing 15 minutes, terminates mortar depositing construction.
The method can be administered highway preferably and to be underlied macroscopic-void and full-water goaf, first this improvement difficult problem of macroscopic-void full-water goaf is overcome, the method utilizes class concrete can effective filling macroscopic-void goaf, utilize Cement fly ash to carry out crack grouting, thus realize the object in comprehensive regulation highway goaf; Next overcomes the goaf harnessing engineering difficult problem in the inconvenient location of curtain.This administering method is with strong points, cheap, turns waste into wealth, safety and environmental protection, has good social benefit and considerable economic benefit.
Accompanying drawing explanation
Fig. 1 is goaf harnessing artwork.
Detailed description of the invention
Below in conjunction with accompanying drawing, specific embodiments of the invention are described in detail.
A kind of highway goaf harnessing method, as shown in Figure 1, comprises the steps:
(1) fixed point pore-forming
Total powerstation is adopted to carry out field survey setting-out according to the coordinate of design boring, boring deviations of actual position is no more than 0.5m in principle, because of landform, atural object impact can not setting-out time, need to be adjusted after design liaison and chief supervision engineer confirm and bore position deviation distance after adjusting should not be greater than 3m.
Boring, all in earth's surface construction, adopts the perforate of Φ 146mm drill bit, and after being drilled into complete basement rock 6m, lower Φ 140mm sleeve pipe retaining wall, then reducing Φ 133mm, be drilled into below seat earth 1m.
(2) differentiate grout hole type and build orifice tube
Determining grout hole classification according to creeping into information summary differentiation, when occurring falling that brill is greater than the situation of 0.5m in drilling process, determining that this hole is for filling with class concrete hole; Injected hole is defined as when occurring falling that brill is less than the situation of 0.5m in drilling process.
Building orifice tube adopts sleeve pipe as filling concrete pipe and Grouting Pipe, and build with plain-water slurry liquid, port, ground welded flange fills with concrete and grouting equipment in order to link.
(3) class concrete is poured into
Class concrete material: portland slag cement, flyash, medium sand, gangue and high efficiency water reducing agent the indices of random inspection class concrete paste, comprises the slump, consolidating strength etc.Cavity, goaf should be filled and water-filling cavity is carried out to extrusion drainage displacement filling by first pumping class concrete body of paste during construction.Gangue maximum particle diameter should be less than 40mm.
Preparation class concrete mixing plant is with reference to " design of common concrete proportioning code " JGJ55-2011, and the class concrete of the suitable pumping of preparation carries out pumping pressure bashing cavity.
(4) perfusion class concrete is stopped
In the latter stage of perfusion class concrete, pump pressure can raise gradually, when orifice tube place pressure limiting valve is opened automatically, stops perfusion class concrete.According to the pressure size of structure type determination pressure limiting valve, pressure limiting valve pressure size is at 3.0 ~ 6.0MPa.
(5) slip casing by pressure
After perfusion class concrete terminates, to being judged to be that slip casing by pressure construction is carried out in the boring of injected hole.
Sequence of construction: by the incline direction in goaf, the injected hole near the injected hole of gob floor absolute altitude lower position of first constructing and structure, then construct to center deployment along inclined direction from low to high, by edge;
Slip casing by pressure: slip casting adopts concentration of slurry first rare rear thick method, and special messenger should be sent after slip casting starts to be responsible for Real Time Observation record pump pressure and midge amount, and adjust grouting amount and slip casting concentration in time according to actual conditions, thin pulp groundwater increment is preferably 50% of single hole grouting amount;
If when there is a large amount of running pulp of surface cracks in slip casting process, batch (-type) slip casting should be adopted or reduce grouting pressure, stoping slurries to run off in a large number from ground.
(6) slip casting is stopped
In the slip casting latter stage of injected hole, pump pressure raises gradually, and when pump amount is less than 70L/min, according to structure type and goaf feature, aperture pressure stability, at 1.0 ~ 3.0MPa, when continuing 15 minutes, terminates mortar depositing construction.
Class concrete, i.e. class concrete filling material in said method step (3), as follows:
1, raw material are selected
(1), consider Shanxi Province's material and draw materials conveniently, financial cost and the conservation value to environment, select flyash, gangue as the concrete main composition material of class, turn waste into wealth, realize recycling of resource; Select the gangue of 5 ~ 20mm particle diameter, form the concrete cage construction of class, form effective strength support; Select flyash and medium sand as batching, be filled with gangue form space between skeleton, overallly form the rational compound of grating, the concrete of some strength can not only be formed, the requirement of compactness can also be met; And the final class concrete formed can meet the transmission demand of pumping, can fill goaf more easily.
2, material mixture ratio and strength test
Material particle size is in table 1:
Table 1 title material and particle diameter (mm)
Proportioning 1, water: cement: flyash: medium sand: gangue=12.4:3.7:13.8:14.1:67.8.
Proportioning 2, water: cement: flyash: medium sand: gangue=12.4:3.4:12.9:13.1:66.3.
Proportioning 3, water: cement: flyash: medium sand: gangue=12.4:3.2:12.05:12.05:60.3.
The preparation method of above-mentioned three kind concretes is as follows:
1, material
(1) cement
1. 32.5 portland slag cements should be selected.
2. the indices of cement should meet " portland slag cement, Portland pozzolana cement and Portland fly ash cement " (GB1344-92) standard-required.
3. when cement is marched into the arena, product certificate or test report should be had, and its kind, label, packed weight and the date of production will be checked.If use front discovery to make moist or expired, test of should resampling.The stacking separately of packed weight deficiency, handles it.
4. the every index of quality of cement quality certificate should meet the regulation in standard.The index of quality comprises content of magnesia, sulfur trioxide content, loss on ignition, fineness, time of setting, soundness, resistance to compression and rupture strength, and class concrete cement consumption should not be greater than 400kg/m
3.
(2) sand
1. sand preferentially should select the hard siliceous sand grains having rib free from foreign meter.
2. sand is divided into carse, medium and small by its fineness modulus.Class concrete material preferentially should select medium sand.
3. the mud content (by weight) of sand, is not more than 5%.
(3) gangue
1. sieve through fragmentation, select the gangue of particle diameter 5-20mm.
2. gangue should be gathered materials on the spot, and selects scleroid former material.
(4) flyash
1. flyash is selected and should be met " lytag and pottery sand " (GB2838-81) standard.
2. the ash of more than three grades qualities should be selected.
(5) water
1. the Drinking Water meeting national standard can mixing class concrete, does not need to test again.
2. according to the non-natural water, contaminated Lake Water, underground water etc. drunk, the regulation that Ying Xianjing inspection meets " concrete mixing water supply standard " (JGJ63-89) could use.
2, facility
1. movable concrete stirring machine is utilized to carry out mix class concrete.
2. platform chessboard, can weigh more than 200kg material, and has CMC to indicate.
3. trolley (trolley).
3, stir
1. according to gangue-cement-medium sand-flyash order according to match ratio carry out feeding intake add water stir 1min.
2. a feeding method is adopted to carry out mix, the strict slump controlling mixture.
The volume of filling solid raw material is fixed as 1m
3, the consumption of each group filler is in table 2.
Table 2 respectively organizes Proportioning of filling materials
To the test block of making, maintenance is after 7 days, 28 days, 60 days as requested, and measure 7 days, 28 days, 60 days uniaxial compressive strengths, result is as shown in table 3:
Table 3 class concrete crushing strength result of the test
According to result of the test, the actual measurement compression strength value of three groups of samples all meets the designing requirement of each highway goaf harnessing.Sample 1 mobility is better, and cohesiveness is good, not bleeding of not emanating; Sample 2 mobility is better, and cohesiveness is good, not bleeding of not emanating; Sample 3 good fluidity, cohesiveness is better, and cohesiveness is better, not bleeding of not emanating.
Sample 3 proportioning class concrete flowability out can meet the requirement of pumping of concrete, and slump is 14cm, and expanding is 28cm.
The concrete unit price of sample 3 proportioning class is out substantially at 112 yuan/m
3left and right, and traditional injecting paste material unit price can increase along with the increase of water-solid ratio, when water-solid ratio is greater than 1:1.2, injecting paste material cost can be greater than the concrete cost of class.
The underground water retained inside macroscopic-void, much larger than the density of water, can arrange by the concrete density of sample 3 proportioning class out, and class concrete has higher calculus rate, can well not stay future trouble by closely knit for the filling of macroscopic-void goaf.
It should be noted last that; above embodiment is only in order to illustrate technical scheme of the present invention and unrestricted; although be described in detail with reference to the embodiment of the present invention; those of ordinary skill in the art is to be understood that; technical scheme of the present invention is modified or equivalent replacement; do not depart from the spirit and scope of technical scheme of the present invention, it all should be contained in claims of the present invention.
Claims (5)
1. a highway goaf harnessing method, is characterized in that: comprise the steps:
(1) fixed point pore-forming
Adopt total powerstation according to design boring coordinate carry out field survey setting-out, boring deviations of actual position be no more than 0.5m, because of landform, atural object impact can not setting-out time, the bore position deviation distance after adjustment is not more than 3m;
(2) differentiate grout hole type and build orifice tube
Determining grout hole classification according to creeping into information summary differentiation, when occurring falling that brill is greater than the situation of 0.5m in drilling process, determining that this hole is for filling with class concrete hole; Injected hole is defined as when occurring falling that brill is less than the situation of 0.5m in drilling process;
Building orifice tube adopts sleeve pipe as filling concrete pipe and Grouting Pipe, and build with plain-water slurry liquid, port, ground welded flange fills with concrete and grouting equipment in order to link;
(3) class concrete is poured into
The class concrete of the suitable pumping of preparation carries out bashing cavity; During construction, pumping class concrete body of paste is filled cavity, goaf and water-filling cavity is carried out to extrusion drainage displacement filling;
(4) perfusion class concrete is stopped
In the latter stage of perfusion class concrete, pump pressure can raise gradually, when orifice tube place pressure limiting valve is opened automatically, stops perfusion class concrete;
(5) slip casing by pressure
After perfusion class concrete terminates, to being judged to be that slip casing by pressure construction is carried out in the boring of injected hole;
Sequence of construction: by the incline direction in goaf, the injected hole near the injected hole of gob floor absolute altitude lower position of first constructing and structure, then construct to center deployment along inclined direction from low to high, by edge;
Slip casing by pressure: slip casting adopts concentration of slurry first rare rear thick method; Thin pulp groundwater increment is 50% of single hole grouting amount;
If when there is a large amount of running pulp of surface cracks in slip casting process, adopt batch (-type) slip casting or reduce grouting pressure, stoping slurries to run off in a large number from ground;
(6) slip casting is stopped
In the slip casting latter stage of injected hole, pump pressure raises gradually, and when pump amount is less than 70L/min, according to structure type and goaf feature, aperture pressure stability, at 1.0 ~ 3.0MPa, when continuing 15 minutes, terminates mortar depositing construction.
2. highway goaf harnessing method according to claim 1, is characterized in that: in step (1), and boring is all constructed on earth's surface, adopt the perforate of Φ 146mm drill bit, after being drilled into complete basement rock 6m, lower Φ 140mm sleeve pipe retaining wall, then reducing Φ 133mm, be drilled into below seat earth 1m.
3. highway goaf harnessing method according to claim 1 and 2, is characterized in that: in step (4), according to the pressure size of structure type determination pressure limiting valve, pressure limiting valve pressure size is at 3.0 ~ 6.0MPa.
4. highway goaf harnessing method according to claim 1, it is characterized in that: in step (3), class concrete comprises 32.5 grades of portland slag cements, flyash, medium sand and gangues, and weight ratio is as follows:
Water: cement: flyash: medium sand: gangue=12.4:3.2 ~ 3.7:12.05 ~ 13.8:12.05 ~ 14.1:60.3 ~ 67.8.
5. highway goaf harnessing method according to claim 4, is characterized in that: the particle diameter of described flyash is 0.005 ~ 0.25mm, and the particle diameter of described medium sand is 0.25 ~ 0.5mm, and the particle diameter of described gangue is 5 ~ 20mm.
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| CN201510159644.XA CN104762950B (en) | 2015-04-07 | 2015-04-07 | Highway goaf harnessing method |
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| CN201510159644.XA CN104762950B (en) | 2015-04-07 | 2015-04-07 | Highway goaf harnessing method |
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|---|---|---|---|---|
| CN105422170A (en) * | 2015-11-02 | 2016-03-23 | 安徽理工大学 | Grouting reinforcement treatment method for mid-depth goaf below building foundation |
| CN107169665A (en) * | 2017-05-19 | 2017-09-15 | 山西省交通科学研究院 | Highway goaf surveying method |
| CN110804917A (en) * | 2019-09-26 | 2020-02-18 | 中国一冶集团有限公司 | Construction method of pressure grouting boundary curtain |
| CN111365066A (en) * | 2020-03-10 | 2020-07-03 | 中国平煤神马能源化工集团有限责任公司 | Step-type water-filling goaf filling method |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105422170A (en) * | 2015-11-02 | 2016-03-23 | 安徽理工大学 | Grouting reinforcement treatment method for mid-depth goaf below building foundation |
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| CN107169665A (en) * | 2017-05-19 | 2017-09-15 | 山西省交通科学研究院 | Highway goaf surveying method |
| CN110804917A (en) * | 2019-09-26 | 2020-02-18 | 中国一冶集团有限公司 | Construction method of pressure grouting boundary curtain |
| CN111365066A (en) * | 2020-03-10 | 2020-07-03 | 中国平煤神马能源化工集团有限责任公司 | Step-type water-filling goaf filling method |
| CN111365066B (en) * | 2020-03-10 | 2021-08-03 | 中国平煤神马能源化工集团有限责任公司 | Step-type water-filling goaf filling method |
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Effective date of registration: 20160429 Address after: 030006 No. 36 West Tan Street, Shanxi, Taiyuan Patentee after: Shanxi Jiao Ke geotechnical engineering Co., Ltd Patentee after: Shanxi Province Transport Science Research Institute Address before: 030006 No. 36 West Tan Street, Shanxi, Taiyuan Patentee before: Shanxi Jiao Ke geotechnical engineering Co., Ltd |