CN103132536A - Drainage technology of geologic chemistry before grouting - Google Patents

Abstract

The invention discloses a drainage technology of geologic chemistry before grouting. The chemical grouting comprises the steps of hole drilling, hole flushing and water pressing, non-grouting segment separation, water discharging, chemical grouting construction, grouting closuring, cement replacing and curdling and hole sealing. The water discharging is conducted after the hole flushing and water pressing steps and before the chemical grouting construction. When a grouting plug is installed, an injection tube is installed, and an outlet of the injection tube needs to be placed at the bottom of a hole. The water discharging comprises wind water discharging and chemical grout water discharging. According to the drainage technology of geologic chemistry before the grouting, acetone pre-grouting drainage technology is eliminated, wind blowing is adopted for the pre-grouting, high permeable epoxy resin grouting grout liquid is grouted directly to dewater unitedly, the construction safety is ensured, the chemical grouting cost and environment pollution are greatly reduced, experiments and construction practice prove that the united dewater technology effects meet requirements, the cost control is greatly improved, great improvement of environment protection is achieved, mechanical properties of rock mass after grouting are obviously improved, and design requirements are met.

Description

Water discharge technology before a kind of geologic chemistry grouting

Technical field

The invention belongs to building foundation reinforcement seepage control technique field, especially belong to water conservancy and hydropower dam geological foundation chemical grouting reinforcement seepage control technique field, particularly the water discharge technology before a kind of geologic chemistry grouting.

Background technology

In the construction of hydropower facilities construction, the anti-seepage reinforcing of Dam construction is important construction technology.Common dam drag body complex geologic conditions, the interior weak hyposmosis zone of fracture that may exist that reaches on the curtain line of drag body scope can have a strong impact on the security of operation of dam.After the curtain cementation of completing the fixed of drag body and curtain line, adopt chemical grouting to carry out follow-up reinforcement antiseepage for weak hyposmosis zone of fracture and process.The Chemical Grouting Treatment of weak hyposmosis zone of fracture often reinforcement and antiseepage is taken into account, and chemical grouting material mainly adopts epoxy series slurry material.And epoxy series slurry material is having under the regimen condition, has a strong impact on its solidfied material physical and mechanical property.

For instructing the chemical grouting construction, must carry out the single-point method setting-out to the grout hole section before grouting.Can effectively the hole internal water accumulation is discharged after setting-out, direct relation the treatment effect of chemical grouting.if evacuation aperture internal water accumulation not, the part of these ponding can form emulsion with the chemical grout that pours into subsequently, even another part can direct form with water not be pressed into the crack and rest on wherein, near this not only makes after by water-reducible slurries gelling, the physical and mechanical property of rock mass is relatively poor, as low in velocity of wave, become mould not high, can't reach the index of former designing requirement, and played in advance " screens " to porosity is original with regard to the not high body (porosity＜10%) of being filled with, allow the pure slurry that arrives subsequently be difficult to pour into, both all can cause the serious hidden danger of quality of chemical grouting.

Before adopting epoxy grouting material to carry out chemical grouting, draining is the important component part of construction technology.Existing hole internal drainage mainly adopts the construction technology of pre-filling acetone.Before grouting, adopt acetone that the hole internal water accumulation is clamp-oned in the stratum.But fill with in advance acetone at the curtain hole that hole depth is very dark, because every hole chemical grouting section is inferior more, adopt acetone to catch up with water, the acetone consumption is huge, and the acetone burning-point is lower, and the security risk of produced on-site is large.

Summary of the invention

The present invention discloses the front water discharge technology of a kind of geologic chemistry grouting according to the deficiencies in the prior art.The problem to be solved in the present invention is to provide a kind of pre-filling acetone construction technology of abandoning, in conjunction with drilled grout hole work progress, safer, more friendly to environment, the material cost that also significantly reduced simultaneously chemical grouting and the novel water technology of catching up with of uniting of risk of environmental pollution.

The present invention is achieved through the following technical solutions:

Water discharge technology before geologic chemistry grouting, it is characterized in that: described chemical grouting comprises boring, bore flushing and setting-out, the isolation of non-filling section, draining, chemical grouting construction, closes slurry, cement displacement and treat solidifying and sealing of hole step, described draining is adopted to unite and is caught up with the water conservancy project skill, unites and catches up with water to comprise wind draining and chemical pulp draining.

Further unite and catch up with the water conservancy project skill to comprise:

Water discharge time: carry out after bore flushing and setting-out step, before chemical grouting construction;

Draining is prepared: carry out the installation of Grout-jetting pipe when after boring is completed, packer being installed, the Grout-jetting pipe outlet must be at the bottom of the hole;

Drain step: at first adopt the air-supply facility that wind is blown in the hole from return pipe, open inlet pipe, the hole internal water accumulation is discharged from inlet pipe; Then the employingization pump priming in the inlet pipe injection hole, is opened return pipe with chemical grout, with slurries, ponding residual in the hole is ejected outside the hole, until ponding and pulp-water mixture drain return out pure slurry in the hole after, close the overfall valve, the beginning chemical grouting.

Helpfulness of the present invention: the present invention takes full advantage of existing construction equipment in conjunction with the chemical grouting construction characteristic, and the Precise control operating procedure is abandoned pre-filling acetone, the technique of driving in advance rock mass water; Adopt the wind walkthrough, directly pour into high osmosis type epoxy resin grouting slurries and unite and catch up with water; Reduce in a large number job site acetone amount of storage, guaranteed safety; Simultaneously owing to no longer pouring into acetone; decrease chemical grouting cost and risk of environmental pollution; experiment and the present invention of engineering practice proof unite and catch up with water conservancy project skill drainage effect to meet the requirements; cost control improves a lot; obtained huge progress in environmental protection; after filling with, the every mechanical index of rock mass improves obviously, meets design requirement.

Description of drawings

Fig. 1 is chemical grouting technique schematic block diagram of the present invention;

Fig. 2 is drainage technology construction schematic diagram of the present invention.

In figure, the 1st, inlet pipe, the 2nd, return pipe, the 3rd, packer, the 4th, valve, the 5th, orifice tube, the 6th, boring, the 7th, weak hyposmosis zone of fracture, the 8th, ground.

The specific embodiment

Below by embodiment, the present invention is conducted further description; the present embodiment only is used for the present invention is further detailed; but can not be interpreted as limiting the scope of the invention, those skilled in the art can make some nonessential improvement and adjustment belongs to the scope of protection of the invention according to foregoing.

In conjunction with Fig. 1 and Fig. 2.

The chemical grouting step that comprises drainage technology

(1) boring

Boring aperture should adopt slim-hole drilling, and the hole of minimizing slurries accounts for and pipe accounts for, and generally adopts φ 75mm or φ 56mm.

Perforate is adopted if first paragraph is non-filling section

Diamond bit crept into to the non-filling section section end, adopted

Seamless steel pipe carries out the orifice tube castingin, adopts φ 56mm aperture with hypomere.

If first paragraph is grout compartment, chemical grouting is carried out the orifice tube castingin after finishing, in order to adopt the aperture closure grouting, anti-on-slip plug occurs.

(2) bore flushing and setting-out

For preventing that landwaste, rock dust from stopping up the slurries diffusion admittance, boring should be carried out bore flushing (crack flushing) after finishing.Adopt conduit to pass into great deal running water, rinse outside the hole at the bottom of the hole, until the backwater clarification; The crack is rinsed and is adopted press water pulsation flushing, flushing pressure to be 80% grouting pressure but to be not more than 1.0MPa, and washing time is no less than 20min.

Carry out packer permeability test after each section of chemical grouting section bore flushing is clean, to judge the permeability on stratum.When permeability large as＞during 1lu, first carry out (wet-milling) cementation filling the 0.2mm crack, in case grouting liquid range of scatter crosses wide and cause the slurries waste and be difficult for finishing, then carry out chemical grouting; When permeability hour as≤1lu, can directly carry out chemical grouting.

(3) non-filling section isolation

Method one: the cement grout castingin seamless steel pipe that adopts 0.5:1; Chemical grouting can be adopted the aperture sealing or the disabler card is carried out chemical grouting bottom steel pipe.

Method two: adopt have that initial viscosity is higher, the viscosity rise rapid hardening chemical grouting material perfusion of prescribing a time limit or limit the quantity of faster, to reach sealing effect.

But above two kinds of methods are Integrated using also, and conventional method one is used for the above non-filling section of first paragraph chemical grouting, and method two is used for the following non-filling section of first paragraph chemical grouting.

Non-filling section and grout compartment determine it is according to the previous disclosed position of fault of geology exploratory hole, draw the distribution map of weak hyposmosis band, the weak hyposmosis band in the section of hole is divided into grout compartment and remainder is divided into non-filling section according to the distribution map of weak hyposmosis band;

Non-filling section isolated operation, non-the fillings section employing geological drilling rig of aperture section crept into to non-the fillings section section end,, carried out the realization of orifice tube castingin with the cement grout of 0.5:1 or chemical grouting material and sealed and isolate down to non-the fillings section section end with seamless steel pipe; A non-filling section employing geological drilling rig between grout compartment crept into to non-the fillings section section of the need isolation end, adopted the rapid hardening chemical grouting material to pour into to realize sealing to isolate.

The perfusion of limiting the quantity of: can finish grouting when groundwater increment reaches single 10Kg/m of notes.

Perfusion in limited time: finish grouting after the perfusion notes time reaches 8h.

(4) draining,

In conjunction with Fig. 2, when being installed, packer carries out the installation of Grout-jetting pipe after boring is completed, and the Grout-jetting pipe outlet must be at the bottom of the hole.

The first step: adopt the air-supply facility that wind is blown in the hole from return pipe, open inlet pipe, the hole internal water accumulation is discharged from inlet pipe.

Second step: the employingization pump priming is opened return pipe in chemical grout is injected from inlet pipe, with slurries, ponding residual in the hole is ejected in the hole.Because present conventional epoxy grouting material density used is slightly larger than water, and the solubility of water in slurry is very little, but energy emulsification, therefore available being injected in the hole drains the water away, or after standing a period of time, after slurry-aqueous mixtures (emulsion) separates voluntarily, then from slurry traversing valve doorway discharge.

Until ponding and pulp-water mixture drain return out pure slurry in the hole after, close the overfall valve, begin grouting.

(5) chemical grouting construction

1. viscosity is controlled

According to above chemical grouting mechanism, the chemical grouting process should be followed " longly last, low rate, infiltration infiltrating irrigation " principle.For preventing that the long reperfusion serosity viscosity of lasting from increasing impact and infiltrate the infiltrating irrigation effect, used first " viscosity-time " hyperbola, and configure at the construction field (site) viscometer slurry viscosity is observed, when finding that viscosity is excessive, change fresh slurries.

Concrete operations are: slurry material and the proportioning used are carried out viscosity test, test the variation that its viscosity is passed in time, draw " viscosity-time " hyperbola according to test data.

When the viscosity of slurry material surpassed 100mp ﹒ s, the infiltration infiltrating irrigation effect of slurries in the stratum was lower.Therefore when the viscosity of slurry material surpasses 100mp ﹒ s, should pour into renewing bright slurries.For instructing, during the time that viscosity 100mp ﹒ s is corresponding on curve around, change fresh slurry filling when the slurries that configure take " viscosity-time " hyperbola of drawing.

2. speed is controlled

With low rate, long-time lasting the infiltration pours into, and generally charge velocity should be controlled between 0.05L/min.m～0.1L/min.m.When injection rate≤0.05L/min.m, the grouting pressure that should suitably raise when injection rate 〉=0.1L/min.m, needs suitably to reduce grouting pressure or control injection rate.

Grouting pressure is controlled: lasts nature with grouting and rises, but when surpassing into slurry speed control criterion, to advance to starch speed as control criterion.

3. termination condition is in the milk

Under design pressure, every 10min surveys and reads once, and after in 1h, continuous 4 reading injection rates all were not more than 0.001L/min.m, Continuous Perfusion 4h can finish grouting, was less than 40h but be in the milk last.For guaranteeing that chemical grout has certain penetration range, reach quality requirement, control again penetration range excessive, avoid engineering cost too high, do not satisfy above-mentioned condition as injection rate, should extend grouting time to satisfying ending standard, but every section grouting time should not surpass 72h.

(6) close slurry, cement displacement and wait to coagulate

The modified epoxy grouting material initial viscosity is low, operable time is long, returns and oozes for preventing from pouring into chemical grouting material in rock mass, after the grout compartment chemical grouting finishes, closes immediately into (returning) slurry valve and closes slurry, treats that gauge hand returns naturally zero.

After the slurry end was closed in chemical grouting, employing grouting facility in the return pipe injection hole, were opened the inlet pipe valve with cement paste simultaneously, and chemical grout is ejected in the hole from inlet pipe.After the cement displacement, treat that solidifying 8h can carry out cleaning bottom of hole; The chemical grout that displaces focuses on after can collecting.

(7) sealing of hole

Sealing of hole adopts 0.5:1 class g cement underflow to replace chemical grout in the hole, after replacement completion, carries out pure pressure type grouting, and sealing of hole pressure is the large grouting pressure of this Kongzui, Grain filling duration 60min.The grouting sealing of hole is after cement grout solidifies until the hole in, and the vacant part in grout hole top during greater than 3.0m, should adopt mechanical mud jacking to continue sealing of hole, during less than 3.0m, makes water sand mud artificial packing reality.

Construction equipment all can be bought, and comprising: rig adopts XY-2 or XY-2B rig; Cementation and setting-out adopt 3SNS high pressure grouting pump, and JD-125/10ization filling proportioning pump is adopted in chemical grouting; Drainage plant adopts small-sized air compressor.

Case history

The Chemical Grouting Treatment of domestic certain left bank, one-level power station F5 tomography, Flc13 tomography, F2 tomography, lamprophyre arteries and veins has adopted non-filling section isolation skill art ﹑ to unite and has caught up with water technology and cement replacement technique.

" wind-slurry " united and caught up with the water technology to abandon pre-filling acetone, and the technique of driving in advance rock mass water is directly poured into high osmosis type epoxy resin grouting slurries; Reduce in a large number job site acetone amount of storage, guaranteed safety; Simultaneously owing to no longer pouring into acetone, decrease chemical grouting cost and risk of environmental pollution.

By the improvement to above-mentioned technique; left bank, power station weak hyposmosis zone of fracture Chemical Grouting Treatment has been completed construction task satisfactorily within the construction period; be greatly improved in cost control; obtained huge progress in environmental protection; after filling with, the every mechanical index of rock mass improves obviously, meets design requirement.

Claims (2)

1. the water discharge technology before a geologic chemistry is in the milk, it is characterized in that: described chemical grouting comprises boring, bore flushing and setting-out, the isolation of non-filling section, draining, chemical grouting construction, closes slurry, cement displacement and treat solidifying and sealing of hole step, described draining is adopted to unite and is caught up with the water conservancy project skill, unites and catches up with water to comprise wind draining and chemical pulp draining.

2. the water discharge technology before geologic chemistry is in the milk according to claim 1, it is characterized in that: the described associating catches up with the water conservancy project skill to comprise:

Water discharge time: carry out after bore flushing and setting-out step, before chemical grouting construction;

Draining is prepared: carry out the installation of Grout-jetting pipe when after boring is completed, packer being installed, the Grout-jetting pipe outlet must be at the bottom of the hole;

Drain step: at first adopt the air-supply facility that wind is blown in the hole from return pipe, open inlet pipe, the hole internal water accumulation is discharged from inlet pipe; Then the employingization pump priming in the inlet pipe injection hole, is opened return pipe with chemical grout, with slurries, ponding residual in the hole is ejected outside the hole, until ponding and pulp-water mixture drain return out pure slurry in the hole after, close the overfall valve, the beginning chemical grouting.

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