CN112267430A

CN112267430A - Hydraulic tunnel expansion joint infiltration is administered structure

Info

Publication number: CN112267430A
Application number: CN202011336380.8A
Authority: CN
Inventors: 王静静; 毛少波; 赵利军; 王金磊; 齐亚静; 肖义
Original assignee: Tianjin Water Planning Survey And Design Co Ltd
Current assignee: Tianjin Water Planning Survey And Design Co Ltd
Priority date: 2020-11-25
Filing date: 2020-11-25
Publication date: 2021-01-26

Abstract

The invention discloses a water seepage treatment structure for an expansion joint of a hydraulic tunnel, wherein a drain pipe for leading seepage water to a drainage blind ditch, a plugging layer formed by filling quick plugging agent for sealing seepage water, a water swelling adhesive tape and a high-elasticity mortar layer with a trapezoidal section are sequentially arranged in the expansion joint from the side of surrounding rocks to the water facing side; the expansion joint is characterized in that single-component polyurea base layers are coated on the surfaces of the lining concrete on the two sides of the expansion joint, a tire base cloth is laid at the position of the expansion joint to cover the expansion joint, and single-component polyurea protective layers are arranged on the outer sides of the tire base cloth and the single-component polyurea base layers through coating. The invention adopts the measures of the structural type of combining the water seepage blocking and the drainage, prevents the calcium from continuously separating out by blocking the gap, effectively prevents the calcium from further separating out, and simultaneously discharges the water outside the surrounding rock to reduce the pressure of the outside water.

Description

Hydraulic tunnel expansion joint infiltration is administered structure

Technical Field

The invention relates to the technical field of expansion joint treatment, in particular to a hydraulic tunnel expansion joint water seepage treatment structure.

Background

Tunnels are a major structural form in hydraulic buildings. In the design of hydraulic buildings, reasonable parting blocks can reduce the influence of temperature stress, thereby reducing cracks. The tunnel split can be divided into a transverse split (circumferential split perpendicular to the longitudinal axis of the tunnel) and a longitudinal split (a split along the longitudinal axis of the tunnel). The transverse seam has two types of expansion joint and working seam. According to the specification of SL279-2002 'design code for hydraulic tunnels', expansion joints are arranged at places with obviously changed geological conditions of surrounding rocks (such as large faults, weak broken zones and the like) or other places which are easy to generate large relative displacement, and corresponding anti-seepage measures are taken. Expansion joint: a structural joint is provided at an appropriate position along the direction of a construction joint of a building or a structure to prevent the structure from cracking or breaking due to a change in the weather temperature of the structural members of the building. And (3) in the tunnel body section with uniform geological conditions, only construction joints are arranged, the spacing between the construction joints is determined according to the analysis of factors such as pouring capacity, temperature shrinkage and the like, and generally 6-12 m can be adopted. The circumferential construction joint of the non-pressure tunnel has no need of roughening the joint surface and setting no water stop if no seepage-proofing requirement exists, and necessary joint treatment measures are adopted according to specific conditions if the seepage-proofing requirement exists. The longitudinal joints are mostly construction joints in the concrete pouring process, are generally arranged near the turning points of the structure and at the positions with smaller internal force of the structure, are carefully treated according to the standard regulation, and key slots and inserted bars are arranged if necessary to ensure the integrity of the lining. In the operation process of the hydraulic tunnel, the water seepage of the expansion joint and the strength of the peripheral concrete are seriously damaged, the water seepage separates out calcium in the concrete on two sides of the joint under the action of dissolution and filtration, the strength of the peripheral concrete is reduced, and the safety of the tunnel structure is threatened. As can be seen from the analysis, the treatment of the water seepage of the expansion joint has certain engineering significance. The expansion joint is treated by recovering the function of the original expansion joint, namely, rigid materials cannot be filled in the expansion joint, and the expansion joint is effectively plugged to prevent water seepage.

Disclosure of Invention

The invention aims to solve the problem that the strength of peripheral concrete is reduced due to water seepage of an expansion joint, and provides a concrete expansion joint.

The technical scheme adopted for realizing the purpose of the invention is as follows:

a water seepage treatment structure for an expansion joint of a hydraulic tunnel is characterized in that a drain pipe for leading seepage water to a drainage blind ditch, a plugging layer for sealing the seepage water and formed by filling a quick plugging agent, a water-swelling adhesive tape and a high-elasticity mortar layer with a trapezoidal cross section are sequentially arranged in the expansion joint from the side of surrounding rocks to the water-facing side; the expansion joint is characterized in that single-component polyurea base layers are coated on the surfaces of the lining concrete on the two sides of the expansion joint, a tire base cloth is laid at the position of the expansion joint to cover the expansion joint, and single-component polyurea protective layers are arranged on the outer sides of the tire base cloth and the single-component polyurea base layers through coating.

Preferably, the thickness of the single-component polyurea protective layer is at least 4 mm.

Preferably, the high-elasticity mortar layer is filled in an inverted trapezoidal groove formed by groove removing processing of concrete on two sides of the expansion joint from the water facing side end of the expansion joint to the surrounding rock side.

Preferably, the inner surface of the inverted trapezoidal groove is coated with an impermeable coating to form an impermeable coating layer.

Preferably, the water-swelling rubber strip is extruded in the middle by a high-elasticity mortar layer filled in the inverted trapezoidal groove and the plugging layer.

The invention adopts the measures of the structural type of combining the water seepage blocking and the drainage, prevents the calcium from continuously separating out by blocking the gap, effectively prevents the calcium from further separating out, and simultaneously discharges the water outside the surrounding rock to reduce the pressure of the outside water.

Drawings

Fig. 1 is a schematic view of the hydraulic tunnel expansion joint water seepage control structure of the present invention.

Detailed Description

The invention is described in further detail below with reference to the figures and specific examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The invention aims to solve the problem that the strength of peripheral concrete is reduced by water seepage in a joint, firstly, fillers in an original expansion joint are removed, a drainage hose is embedded to drain the seepage water to a drainage blind ditch, then, water swelling adhesive tapes are filled, high-elasticity mortar is filled on the surface of the joint, single-component polyurea is coated on the surface of the expansion joint, and finally, drain holes are additionally formed in side walls on two sides to drain the water.

As shown in fig. 1, in the water seepage control structure for the expansion joint of the hydraulic tunnel, a drain pipe 3 for leading seepage water to a drainage blind ditch, a plugging layer 6 formed by filling a quick plugging agent for sealing seepage water, a water-swelling adhesive tape 4 and a high-elasticity mortar layer 5 with a trapezoidal section are sequentially arranged in the expansion joint from the surrounding rock side to the water-facing side; the surface of the lining concrete 7 on the two sides of the expansion joint is coated with a single-component polyurea base layer, the expansion joint is covered by tire base cloth 2, and a single-component polyurea protective layer 1 is arranged on the outer sides of the tire base cloth and the single-component polyurea base layer through coating.

The construction process of the hydraulic tunnel expansion joint water seepage treatment structure comprises the following steps:

1) cleaning the expansion joint and the peripheral concrete surface, polishing the expansion joint within 150mm of each side, and enhancing the bonding of the coating and the concrete.

2) Removing filler in the original seam, burying a drainage hose to drain the seepage water to the drainage blind ditch, and providing conditions for dry field operation.

3) The rapid plugging agent is used for sealing the water seepage, and the water-swelling adhesive tape is embedded.

4) And the concrete grooves at the two sides of the expansion joint are removed, and the expansion joint is in an inverted trapezoid shape.

5) The inner surface of the trapezoid groove is coated with anti-seepage coating and filled with high-elasticity mortar.

6) The surfaces of the concrete 7 lined at the two sides of the expansion joint are coated with the first layer of single-component polyurea, the expansion joint is paved with the tire base cloth, and then the single-component polyurea is coated and brushed for 2-3 times until the thickness of the single-component polyurea at the expansion joint reaches 4 mm.

7) Drainage holes are additionally arranged on the side walls at two sides of the expansion joint at a distance of 30cm, the drainage holes are arranged at two sides of the expansion joint in a quincunx shape at an interval of 1m and are inserted into the expansion joint at an angle of 45 degrees, 8 expansion joints are arranged, and 4 expansion joints are arranged on each side wall. The drainage holes are additionally arranged, so that the external water pressure of the lining can be reduced, and the treatment effect is guaranteed.

The conventional design of expansion joint water seepage treatment is that on the premise of temporary punching, drainage and water seepage are induced, GB glue is used for plugging after slotting, rapid hardening mortar is used for the surface, and compared with the prior art, the improved treatment structure mainly has the following advantages:

1) the drainage hose is embedded to guide and drain the seepage water, the quick plugging agent is used for sealing the seepage water, the water swelling adhesive tape is embedded, and finally the side walls on two sides are additionally provided with drainage holes, and the drainage holes are arranged together for plugging and draining, so that conditions are created for surface dry field operation and the seepage water is prevented.

2) The lining surfaces on the two sides of the expansion joint adopt single-component polyurea and are covered with tire base cloth. The single-component polyurea composite tire base cloth seals the surface of the expansion joint, so that the phenomena of stress concentration at the joint and coating thinning can be avoided while the sealing effect is enhanced.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. A water seepage control structure for an expansion joint of a hydraulic tunnel is characterized in that a drain pipe for leading seepage water to a drainage blind ditch, a leakage blocking layer formed by filling quick leakage blocking agents for sealing seepage water, a water swelling adhesive tape and a high-elasticity mortar layer with a trapezoidal section are sequentially arranged in the expansion joint from the side of surrounding rocks to the water facing side; the expansion joint is characterized in that single-component polyurea base layers are coated on the surfaces of the lining concrete on the two sides of the expansion joint, a tire base cloth is laid at the position of the expansion joint to cover the expansion joint, and single-component polyurea protective layers are arranged on the outer sides of the tire base cloth and the single-component polyurea base layers through coating.

2. The hydraulic tunnel expansion joint water seepage treatment structure as claimed in claim 1, wherein the thickness of the one-component polyurea protective layer is at least 4 mm.

3. The hydraulic tunnel expansion joint water seepage treatment structure as claimed in claim 1, wherein the high elasticity mortar layer is filled in an inverted trapezoid groove preformed by groove removing processing of concrete on two sides of the expansion joint from the water facing side end to the surrounding rock side of the expansion joint.

4. The hydraulic tunnel expansion joint water seepage treatment structure as recited in claim 3, wherein the inner surface of the inverted trapezoidal groove is coated with an anti-seepage coating to form an anti-seepage coating layer.

5. The hydraulic tunnel expansion joint water seepage treatment structure as claimed in claim 3, wherein the water-swellable adhesive tape is extruded in the middle by a high-elasticity mortar layer filled in the inverted trapezoid groove and a plugging layer.