CN112195970A - River-crossing tunnel engineering waterproof construction method - Google Patents

Abstract

The invention discloses a river-crossing tunnel engineering waterproof construction method, which comprises the waterproofing of a main structure and an auxiliary structure of an open excavation section, construction joints, deformation joints, pile heads, wall-penetrating pipe boxes, dewatering wells, lattice columns and the like, wherein the main structure and the auxiliary structure of the open excavation section comprise a bottom plate, side walls and a top plate, and are waterproof, and a drainage prevention mode with the self-waterproofing of reinforced concrete and the combination of flexible waterproof layers is adopted; the waterproof construction method comprises the steps of constructing the construction joints, the deformation joints, the pile heads, the wall penetrating pipe boxes, the dewatering wells, the lattice columns and the like, wherein the waterproof construction is assisted by water stopping components, the construction joints are arranged at construction sections and layering positions, and the deformation joints are arranged at construction section positions.

Description

River-crossing tunnel engineering waterproof construction method

Technical Field

The invention belongs to the technical field of building construction, and particularly relates to a river-crossing tunnel engineering waterproof construction method.

Background

The tunnel through the river often has strong regionality, and has great relevance with local engineering geology, hydrogeological conditions, construction machines, experience, hydrogeological conditions, environmental conditions and the like.

Cold contraction cracks, dry contraction cracks and the like are easy to occur in the construction process, the deformation of the enclosure structure is strictly controlled in the construction process, the flatness and the non-cracking of the base surface of the enclosure structure are ensured, the enclosure structure has no open water or water dripping and leaking phenomena during construction, and a small amount of wet stains are allowed to exist on the waterproof base surface. Therefore, the water prevention of the tunnel crossing the river is a system project, and requires that the building structure is closely matched with the water prevention, and the water prevention is combined with the durability. In the river-crossing tunnel construction, deformation joints, construction joints, induction joints and the like are often involved, so that the waterproof performance of the whole tunnel is necessarily influenced by detailed construction of the deformation joints, the construction joints, the induction joints, the wall-penetrating pipe boxes, the embedded parts, the reserved channel joints, the open cut and interval joints, the pile heads, the corners and the like. But no relevant detailed report of waterproof construction exists at present.

Disclosure of Invention

Aiming at the problems in the prior art, the invention aims to provide a waterproof construction method for river-crossing tunnel engineering.

The river-crossing tunnel engineering waterproof construction method is characterized by comprising the waterproofing of a main structure and an auxiliary structure of an open excavation section, the waterproofing of a construction joint, a deformation joint, a pile head, a wall-penetrating pipe box, a dewatering well, a lattice column and the like, wherein the main structure and the auxiliary structure of the open excavation section comprise a bottom plate, a side wall and a top plate, and the drainage prevention mode which mainly adopts the self-waterproofing of reinforced concrete and combines a flexible waterproof layer is adopted; the construction joint, deformation joint, pile head, wall-penetrating pipe box, precipitation well, lattice column and the like are waterproof assisted by a water stop component, the construction joint is arranged at the construction section and the layering position, and the deformation joint is arranged at the construction section position.

The river-crossing tunnel engineering waterproof construction method is characterized in that the waterproof construction process of the bottom plate, the side wall and the top plate comprises the following steps: concrete base cushion press polishing → base surface cleaning → chamfering treatment of the female corner part and the male corner part → laying of the waterproof coiled material reinforcing layer of the female corner part and the male corner part → laying of the waterproof coiled material in a large area → inspection and acceptance → fine stone concrete protection layer → construction of a structural layer.

The river-crossing tunnel engineering waterproof construction method is characterized in that a construction process for waterproofing a bottom plate, a side wall and a top plate comprises the following steps:

1) concrete base cushion press polish

2) Base surface treatment

a. The concrete base cushion layer and the surface of the enclosure structure cannot have open water, and when no open water exists on the surface of the concrete base cushion layer, a leveling layer is applied to the part of the enclosure structure, the surface flatness of which does not meet the design requirement;

b. when the width of the crack of the concrete base cushion layer is more than or equal to 1.5mm, embedding and filling, and embedding and filling cement mortar or bentonite waterproof slurry on the plane of the V-shaped groove of the joint-drilling chisel;

c. the side wall connected with the concrete base cushion bottom plate adopts 1: 2.5 leveling cement mortar;

d. leveling the surface of the leveling layer;

(3) all the internal and external corner parts adopt 1: 2.5, preparing the cement mortar into 50x50mm mortar chamfers;

self-adhesive waterproof coiled material laying

a. Spreading a waterproof coiled material with the PE film upward, and laying the coiled material at the positions of the internal corner and the external corner and the positions with joints to obtain a waterproof coiled material reinforcing layer;

b. the waterproof coiled material is unfolded and placed at a position needing to be made into a waterproof part, the coiled material is fixed on the base layer by a cement nail, the bonding surface faces outwards to uncover the isolating film on one side, which is bonded with the self-adhesive coiled material fixed on the base layer, the isolating film is rolled and paved while being torn, the coiled material is bonded with the previous coiled material, after the bonding is finished, the other coiled material is remade according to the method, and the high-molecular self-adhesive film waterproof coiled material is paved in a large area, so that the high-molecular self-adhesive film;

c. rolling: compacting the whole surface of the adhered high-molecular self-adhesive film waterproof coiled material by a compression roller in sequence, wherein the overlapped part needs to be rolled; applying a rubber hammer to the special-shaped part and the overlapped T-shaped part for striking tightly; and after the waterproof coiled material construction is finished, the inspection and acceptance are qualified, and then the construction of the fine aggregate concrete protective layer and the structural layer is carried out.

The river-crossing tunnel engineering waterproof construction method is characterized in that a steel plate waterstop is adopted for a construction joint, cement-based permeable crystalline waterproof coating is coated on the structural side of the construction joint, a water-swelling waterstop is arranged on the inner side of the construction joint, the steel plate waterstop is welded on structural steel bars at a fixed interval of 1m, and the waterstop is prevented from falling down when concrete is poured and vibrated; when concrete at the construction joint position is poured and vibrated, the steel plate waterstop is straightened while pouring, so that the steel plate waterstop is prevented from being too large in snake shape and lodging; the concrete at the water stop part is vibrated fully, so that the water stop is tightly occluded with the concrete; and (3) coating cement-based capillary crystalline waterproof materials on the concrete surfaces of the construction joints and the pile heads.

The river-crossing tunnel engineering waterproof construction method is characterized in that a high-molecular self-adhesive film waterproof coiled material is firstly paved at deformation joints of side walls and bottom plates facing water, then a back-attached rubber waterstop or sealant is arranged for caulking, and finally a double-component polysulfide sealant is adopted for waterproofing; when the back-pasted rubber waterstop is arranged, the water-facing side of the top plate is provided with the double-component polysulfide sealant for embedding and filling to form a waterstop ring; when the sealant is used for caulking treatment, the two-component polysulfide sealant is used.

The river-crossing tunnel engineering waterproof construction method is characterized in that the pile head waterproof construction process is as follows:

firstly, before the cushion layer construction, chiseling out the pile head to the designed elevation position, and removing mud, floating slurry, loose broken stones and the like from the exposed pile body part; then adopting a waterproof layer of a waterproof coiled material of the pile body at the internal corner part of the pile body and the cushion layer, simultaneously filling 10mm of polymer cement-based M10 waterproof mortar at the internal corner part, and adopting cement-based infiltration crystallization waterproof paint to treat the pile body and the pile head part, wherein the thickness is 2.0 mm; and water-swelling water stop strips are arranged at the positions of the pile head reinforcing steel bars and the pile body, and the water stop strips surround the pile body and the pile reinforcing steel bars.

The river-crossing tunnel engineering waterproof construction method is characterized in that the waterproof construction processes of the wall-penetrating pipe, the dewatering well and the like are as follows:

1) wall pipe: welding a steel sheet water stop ring around the pipe wall of the wall penetrating pipe, and arranging sealant at the positions of the water stop ring and the pipe wall in a circumferential direction for sealing; and arranging a double-sided self-adhesive waterproof layer at the internal corner part of the joint of the pipe and the structural surface, and embedding and filling the double-sided self-adhesive waterproof layer with sealant to connect the double-sided self-adhesive waterproof layer into a whole.

2) Dewatering well: the remaining dewatering well is subjected to water pumping construction continuously by penetrating the bottom plate; for a depressurization well needing to be closed, before the construction of a bottom plate, arranging a steel sleeve outside a well pipe of the depressurization well, arranging a water-stopping steel ring outside the steel sleeve, arranging filling M10 waterproof cement mortar at the joint of the water-stopping steel ring and the sleeve, and plugging the depressurization well after the construction of the bottom plate is finished;

3) lattice column: chiseling the pile head of the lattice column upright column pile to a designed elevation, removing soil floating slurry, loose broken stones and the like of the pile head, and then treating the pile head part with 1.0mm cement-based infiltration crystallization waterproof coating; secondly, bonding the waterproof coiled material of the bottom plate and the pile head part by adopting sealant so as to connect the waterproof coiled material of the bottom plate and the pile head part into a whole; and finally, winding two water-swelling water stop strips on the inner wall and the outer wall of the latticed column within the range of the bottom plate respectively to enhance the water stop performance of the latticed column.

By adopting the technology, compared with the prior art, the invention has the following beneficial effects:

1) according to the river-crossing tunnel obtained by the limited method, through observation, the structure has no water leakage phenomenon, no wet stain exists on the surface of the structure, and the total wet stain area is 2/1000 smaller than the total waterproof area; and the moisture stain on any 100m waterproof area is not more than 3, the maximum area of a single moisture stain is not more than 0.2 m; average water seepage amount is not greater than 0.05L/(m d), and the water seepage amount on any 100m waterproof area is not greater than 0.15L/(m d);

2) the concrete adopts a double-doping technology, the minimum dosage of the gel material is strictly controlled, the minimum dosage is not less than 300kg/m, the maximum water-gel ratio limit value is 0.45 when the concrete is subjected to heavy harvest and no more than 400 kg/m; the waterproof performance of the construction joint and the deformation joint is further improved by processing the construction joint and the deformation joint.

Drawings

FIG. 1 is a schematic diagram of a waterproof structure of corner portions of a bottom plate and a side wall of the invention;

FIG. 2 is a schematic diagram of a waterproof structure of corner portions of a top plate and a side wall of the invention;

FIG. 3 is a schematic view of a waterproof construction structure of the construction joint of the present invention;

FIG. 4 is a schematic diagram of a deformation joint waterproof construction structure of the present invention;

fig. 5 is a schematic view of a waterproof construction structure of the pile head of the present invention.

In the figure: 1. a concrete foundation pad layer; 2. an enclosure structure; 3. chamfering mortar; 4. a waterproof roll reinforcing layer; 5. a high molecular self-adhesive film waterproof roll; 6. a fine stone concrete protective layer; 7. constructing a joint; 8. a steel plate waterstop; 9. a water-swelling sealing strip when meeting water; 10. a cement-based capillary crystalline waterproof coating; 11. a back-adhered rubber waterstop; 12. two-component polysulfide sealant; 13. waterproof layer of waterproof coiled material of pile body; 14. a cement-based infiltration crystallization waterproof coating; 15. the pile body is an expansion water stop strip when meeting water; 16. leveling layer; 17. a water-swellable putty strip.

Detailed Description

The invention is further described below, but the scope of protection of the invention is not limited thereto:

as shown in fig. 1-5, the river-crossing tunnel engineering waterproof construction method of the present invention includes waterproofing of the main structure of the open cut section, waterproofing of the auxiliary structure, construction joints, deformation joints, pile heads, wall-penetrating pipe boxes, dewatering wells, lattice columns, etc., the main structure of the open cut section and the auxiliary structure include bottom plates, side walls, and top plates, and the drainage prevention mode that the self-waterproofing of reinforced concrete is mainly adopted and flexible waterproofing layers are combined is adopted; construction joint, movement joint, pile head, wall tube box, precipitation well, the waterproof adoption stagnant water component of grid post etc. are supplementary waterproof, construction segmentation, layering department are located to the construction joint, and the movement joint is located construction segmentation position, specifically is:

1. the structural concrete self-waterproof method is characterized in that the grade of waterproof concrete adopted by the structural concrete self-waterproof method is determined according to the requirements of safety, durability, impermeability and crack prevention of a structure, the grade of structural strength adopts C40P8 waterproof reinforced concrete, the design year is 100 years, the concrete adopts a double-doping technology, the consumption of gel materials is strictly controlled to be 300 kg/m-400 kg/m during transportation, and the maximum limit value of a water-to-glue ratio is 0.45; when the structural concrete is poured, open water cannot be arranged on a base surface, the template is flat and has enough rigidity and strength, and the joint part is tight and does not leak slurry; the concrete is uniformly stirred, the slump in a pump is preferably controlled to be 18 +/-2 cm, the difference value between the slump out of a factory and the slump in a mould is less than 3cm, the self-falling height of the poured concrete is not more than 2m, and the thickness of each layer is not more than 30cm during layered pouring, wherein in order to reduce temperature shrinkage cracks, the cement consumption is limited, and the water-cement ratio (the mass of water, cement and admixture) is controlled to be less than or equal to 0.45;

1.1 waterproof construction process of bottom plate, side wall and top plate: concrete base bed course press polish → base plane clearance (inspection, processing, acceptance) → negative, the external corner position is done the chamfer and is handled → negative, the waterproof coiled material reinforced layer of external corner portion is laid → waterproof coiled material is laid in a large scale → inspection acceptance → fine aggregate concrete protective layer (intensity reaches after the people's condition) → structural layer construction, specifically do:

1.11 calendering of concrete base underlays

1.12 base surface treatment

a. The surfaces of the concrete base cushion layer 1 and the enclosure structure 2 cannot have open water, and when the surface of the base layer has no open water, a leveling layer is applied to the part of the enclosure structure 2, the surface flatness of which does not meet the design requirement;

b. when the width of the basal plane crack is more than or equal to 1.5mm, embedding and filling, namely embedding and filling cement mortar or bentonite waterproof slurry on the plane of the V-shaped groove of the joint drill;

c. the side wall leveling layer connected with the bottom plate adopts 1: 2.5, leveling the cement mortar to obtain a leveling layer 16;

d. the surface of the leveling layer is smooth, the flatness of the leveling layer is checked by using a 2m guiding rule, the gap between the straight rule and the base layer is not more than 5mm, and only gentle change is allowed;

e. the surface of the leveling layer is firm and dry, no open water exists, and no parts such as loose, ash falling, hollowing, cracks, peeling, dirt and the like exist; the base surface flatness requirement should be met: D/L is not more than 1/10, D is the depth of the concave of two adjacent convex surfaces of the base surface, and L is the width of the adjacent base surface;

f. all the internal and external corner parts adopt 1: 2.5, preparing the cement mortar into a 50x50mm mortar chamfer 3;

g. when the downward turning beam is excavated, water is prevented from flowing into the groove, and when the downward turning beam is excavated, water flows towards the two sides of the foundation pit by the gradient;

1.13 laying of self-adhesive waterproof coiled material

a. Spreading a waterproof coiled material, arranging the coiled material at the position of a negative corner and a positive corner with an upward PE film, paving, fixing the coiled material on a base layer by using cement nails, and enabling the bonding surface to face outwards to obtain a waterproof coiled material reinforcing layer 4;

b. unfolding a waterproof coiled material, enabling a PE film to face upwards, arranging the coiled material at a position needing to be waterproof, uncovering an isolation film at one side of a self-adhesive coiled material fixed on a base layer, rolling and paving the self-adhesive coiled material downwards while tearing the isolation film, simultaneously adhering the self-adhesive coiled material with a previous coiled material, and after adhering is completed, remaking another coiled material according to the method to obtain a high-molecular self-adhesive film waterproof coiled material 5;

c. when the temperature is low, a blowtorch can be adopted to bake the sticking part so as to increase the self-adhesiveness of the coiled material;

d. the side wall waterproof layer is continuously paved to the height of 80cm above the upper surface of the top plate, a waterproof coiled material reinforcing layer is applied to the corner part, and the width of the reinforcing layer is 60 cm;

e. the waterproof layers around the reserved holes are protected by composite plates with the thickness not less than 10 mm;

f. rolling: compacting the whole surface of the adhered coiled material by a compression roller in sequence, wherein the overlapped part needs to be rolled; applying a rubber hammer to the special-shaped part and the overlapped T-shaped part for striking tightly;

g. when the coiled material is laid and pasted, air below the coiled material is removed, the coiled material is flat and straight, the lapping size meets the standard requirement, and the coiled material is not twisted or folded;

h. the waterproof coiled material is strictly prohibited from being damaged during side steel bar construction and support template construction, and damaged parts should be timely bonded and repaired to ensure the waterproof effect;

2. the outer waterproof layer-wrapped open-cut tunnel is greatly vibrated and deformed, a double-channel waterproof line is formed by waterproof reinforced concrete and a fully-wrapped flexible waterproof layer, the waterproof layer is laid on the upstream surface of the main structure to form a closed fully-wrapped waterproof layer, the flexible fully-wrapped waterproof layer is formed by a flexible fully-wrapped waterproof coiled material outside the main structure, and the flexible fully-wrapped waterproof layer is sealed in sections during construction so as to further improve the waterproof construction quality; the waterproof capability of the flexible waterproof layer is that the actual water head of underground water is not less than 0.6 MPa;

3 waterproof at the joint

3.1 the construction joints are arranged at the construction subsection and layering position

The construction joint 7 adopts a steel plate water stop 8, cement-based permeable crystalline waterproof coating 10 is coated on the construction joint structure side, a water swelling water stop strip 9 is arranged on the inner side, a deformation joint adopts a high-molecular self-adhesive film waterproof coiled material 5, a back-attached rubber water stop strip 11 and a two-component polysulfide sealant 12 for water prevention, the water stop strip and a grouting pipe are accurately installed, the steel plate water stop strip joint is connected in a full-welding mode, before the next-stage concrete is poured, weak vibration is adopted at the construction joint position, before the concrete is newly poured at the construction joint, the surface of the hardened concrete is subjected to roughening treatment and is fully wetted, and the area of the exposed fresh concrete after roughening is not less than 75% of the total area; if the construction joint is a longitudinal horizontal construction joint, floating slurry and sundries on the surface of the concrete are removed before the concrete is poured, cement mortar with the thickness of 30mm and the thickness of 1:1 is paved after roughening, then cement-based permeable crystalline waterproof coating with the thickness of 2mm is coated, and the concrete is poured in time; if the construction joint is a circumferential construction joint, before concrete is poured, removing surface laitance, brushing cement-based permeable crystallization waterproof coating with the thickness of 2mm, and pouring the concrete in time;

the engineering construction joint water resistance adopts a galvanized steel plate waterstop, and cement-based capillary crystalline waterproof coating with the thickness of 2.0mm is coated on the surface of a construction joint structure; the concrete construction of the construction joint water proofing is as follows:

a. galvanized steel sheet waterstop construction method

Firstly, the steel plate waterstops 8 are welded on structural steel bars at a fixed interval of 1m, so that the waterstops are prevented from falling down when concrete is poured and vibrated;

the dovetail orientation of the steel plate waterstop 8 is favorable for pouring concrete;

and thirdly, when the thickness of the structure is not more than 500mm, the water stop is arranged at the position of the central line of the structure, and the thickness difference of two sides of the structure is not more than 50 mm. The distance between the longitudinal center line of the steel plate water stop 8 and the surface of the construction joint is not more than 30 mm. The waterstop is perpendicular to the surface of the construction joint. When structure thickness is greater than 500mm, the concrete thickness control that the waterstop is close to constructor one side can 250 ~ 300mm, the later stage of being convenient for is handled the maintenance of waterstop.

When concrete at the construction joint part (especially the horizontal construction joint of the side wall) is poured and vibrated, attention should be paid to pouring and righting the water stop belt at the same time, so that the water stop belt is prevented from being too large in snake shape and lodging;

due to the fact that the horizontal construction joint is blocked by the water stop belt, sundries between the water stop belt and the building envelope are difficult to clean, and therefore the horizontal construction joint needs to be carefully cleaned and roughened before construction of the next procedure, as shown in figure 4;

sixthly, the concrete at the water stop part must be vibrated fully, so that the water stop is tightly meshed with the concrete, and a vibrating rod is strictly prohibited from contacting the water stop during vibration;

b. construction method of cement-based permeable crystallization type waterproof material

Firstly, the cement-based permeable crystallization type waterproof material 10 is coated on the concrete surface of a construction joint and a pile head, and the using amount is 1.5kg/m²The double-layer coating is adopted, the interval time between the two layers is determined according to the environmental temperature, the humidity and the material selection and maintenance requirements of construction operation, the final setting time is generally determined by taking the final setting time as the standard, and experiments are needed to determine the final setting time;

secondly, before painting, the surface of the base layer is treated. The surface of the base layer should be firm and clean without floating ash, floating slurry, oil stain, alkali resistance, peeling and loose parts. And roughening and cleaning the surface of the construction joint according to the standard requirement. Cleaning the release agent on the surface of the concrete;

and thirdly, when the base layer is too smooth, the base layer should be polished to be rough. The surface of the base layer is free from accumulated water, and the surface of the base layer is kept wet before being coated;

the cement-based permeable crystalline waterproof material can be constructed by a brushing method or a spraying method according to construction joints (horizontal or vertical) of different parts;

when the coating method or the spraying method is adopted for construction, if the base layer is dried, the base layer is fully wetted; if the ambient temperature is too high, the coating dries too fast, which can cause the coating material to lack water, the hydration reaction does not completely reach the corresponding strength, even cause pulverization. Therefore, the coating should be properly sprayed and moistened in time to ensure that the hydration reaction of the coating is sufficient so as to improve the adhesive strength and permeability of the coating; .

Sixthly, the coating is uniform and cannot be leaked. The coating should not touch or get on the person before it is dried. The painting operation can not be carried out 2 hours before rain. And high-temperature construction (preferably 5-25 ℃) is avoided as much as possible.

3.2. The deformation joint side wall, the deformation joint upstream face of the bottom plate set up the back and stick to the type rubber waterstop 11, the roof is set up the double-component polysulfide fluid sealant 12 to inlay and pack to form the water stopping ring, while constructing, the deformation joint waterstop and water stopping glue are put in place accurately, the waterstop includes the central waterstop and rubber waterstop, the central waterstop must seal the ring, the rubber waterstop joint adopts the small-scale vulcanizer to vulcanize on the spot, the gasket uses the polyethylene board of the medium density among the joints, while pouring the concrete of one side of deformation joint, in order to prevent the waterstop of the other side from receiving the destruction, the template stop board is made into the box, the concrete of the waterstop position vibrates compactly at the same time, guarantee the waterproof effect of the; the joint part of the water stop belt cannot be left at the corner part, the radius of the corner is not less than 30cm, 1-2 layers of reinforced waterproof plates are additionally arranged at the corner, and the differential settlement between the structures at two sides of the deformation joint cannot exceed 10 mm;

the waterproof construction method of the deformation joint comprises the following steps:

a. construction method for back-pasting rubber waterstop

The width of the water stop belt is 35cm, the thickness of the rubber is 10cm, and the thickness of the steel plate is 1 mm. The waterstop adopts the iron wire to fix on the structural reinforcement, and the fixed interval is 40 cm. The fixing is required to be firm and reliable, and the water stop belt is prevented from lodging and twisting due to falling of a fixed point when concrete is poured and vibrated, so that the water stop effect is not influenced;

secondly, horizontally arranged water stops are all installed in a basin shape, the opening of the basin shape is upward, so that bubbles at the lower part of the water stops are smoothly discharged when concrete is poured and tamped, and the included angle between the water stops and the surface of a construction joint is preferably 75-105 degrees;

and thirdly, the field joints of the water stop belts cannot be arranged within 50cm of the two sides of the structure corner, the field joints are as few as possible, and the joints at other joint parts (T-shaped, cross-shaped and the like) except for butt joint all adopt factory joints, so that the joint treatment cannot be carried out on the field. The butt joint can adopt a hot vulcanization method or a cold joint method, the tensile strength of the joint part is not less than 80% of that of the parent metal, and a water-swelling putty block 17 is arranged at the joint;

fourthly, the thickness of concrete on any side of the water stop should not be smaller than 15cm, the longitudinal center line of the water stop should be aligned with the seam, and the distance error between the two should not be larger than 1 cm. The water stop belt is perpendicular to the joint surface, and the error is not more than 15^o；

When pouring and vibrating the concrete at the waterstop part, the waterstop is righted by hands while pouring and vibrating;

sixthly, the template at the position of the water stop belt is accurately and firmly installed and positioned, so that the influence of die running, die expansion and the like on the positioning accuracy of the water stop belt is avoided;

seventhly, the concrete at the water stop part must be vibrated fully, so that the water stop is tightly meshed with the concrete, and a vibrating rod is strictly prohibited from contacting the water stop during vibration;

the steel plate water stop of the construction joint is cut off on the side surface of the steel edge water stop of the induction joint to ensure that the end of the steel plate water stop is attached to the side surface of the steel edge water stop, and then a circle of rubber water stop strip is wound on the end of the steel plate water stop;

b. the sealing gum deformation joint upstream surface adopts the sealing gum to carry out caulking treatment, should adopt two ingredient polysulfide sealing gum 12 to seal, specifically is:

firstly, before caulking, a liner plate with a certain depth in a deformation joint is removed according to the caulking depth required by design, and the concrete surface on the inner surface of the joint is cleaned by a steel wire brush and high-pressure air, so that the surface of the concrete in the joint is clean, dry and solid, and has no impurities such as oil stain, dust, peeling, sand grains and the like. No sundries are accumulated on the surface of the induction joint gasket plate;

secondly, an isolation film is arranged in the seam, the isolation film can be a PE film with the thickness of 0.2-0.3 mm, the isolation film is accurately positioned, and the concrete basal planes on two sides of the seam are prevented from being covered;

thirdly, the glue injection should be continuous, full, even and compact. Closely adhered to the concrete surfaces at the two sides of the joint, and the phenomena of hollowing, air bubbles and separation from the base layers at the two sides are not generated at any part;

fourthly, the surface of the sealant is smooth and does not protrude out of the surface of the joint concrete;

after the caulking is finished and before the sealant is not cured, protection work is required to be done;

sixthly, the top plate upstream surface caulking glue is firmly attached to the side wall externally attached water stop belt.

4. Special part waterproof construction method

a. Pile head waterproof

Firstly, before the cushion layer construction, chiseling out the pile head to the designed elevation position, and removing mud, floating slurry, loose broken stones and the like from the exposed pile body part; then waterproof coiled material waterproof layers are adopted at the internal corner parts of the pile body and the cushion layer, 10mm polymer cement-based M10 waterproof mortar is filled at the internal corner parts, the pile body and the pile head are treated by cement-based infiltration crystallization waterproof coating, and the thickness is 2.0 mm; water-swelling water stop strips 15 are arranged at the positions of the pile head reinforcing steel bars and the pile body, and the water stop strips surround the pile body and the pile reinforcing steel bars, as shown in fig. 5;

b. water-proof construction method for wall pipe and dewatering well

Firstly, wall pipe penetration: welding a steel sheet water stop ring 18 around the wall of the wall penetrating pipe, and arranging a sealant 19 at the position of the water stop ring and the pipe wall in a circular manner for sealing; a double-sided self-adhesive waterproof layer is arranged at the internal corner part of the joint of the pipe and the structural surface and embedded and filled with sealant to connect the pipe and the structural surface into a whole,

a dewatering well: because individual dewatering wells need to be reserved, the dewatering wells need to penetrate through the bottom plate to continue pumping. For the unclosed depressurization well, before the construction of the bottom plate, a steel sleeve is arranged outside a well pipe of the depressurization well, a water stop steel ring is arranged outside the steel sleeve, waterproof cement mortar filled with M10 is arranged at the joint of the water stop steel ring and the sleeve, and the depressurization well is plugged after the construction of the bottom plate is finished.

③ lattice column: chiseling the pile head of the lattice column upright column pile to a designed elevation, removing soil floating slurry, loose broken stones and the like of the pile head, and then treating the pile head part with 1.0mm cement-based infiltration crystallization waterproof coating; secondly, bonding the waterproof coiled material of the bottom plate and the pile head part by adopting sealant so as to connect the waterproof coiled material of the bottom plate and the pile head part into a whole; and finally, winding two water-swelling water stop strips on the inner wall and the outer wall of the latticed column within the range of the bottom plate respectively to enhance the water stop performance of the latticed column.

5. Shield waterproof construction process

The construction process flow comprises the following steps: the method comprises the following steps of cleaning impurities of the pipe piece (including drying) → preparing waterproof materials → smearing adhesive → airing → sleeving and pasting ethylene propylene diene monomer elastic sealing gasket → tightening, troweling → smearing glue → airing → pasting polyurethane elastic sealing gasket → tightening, troweling → smearing glue → airing → pasting neoprene sponge rubber strip → tightening, troweling → pasting nitrile cork rubber gasket → storing the pipe piece, wherein the specific steps are as follows:

5.1 Shield Water-proofing measures

5.1.1 segment is from waterproof

(1) The tunnel segment is made of high-performance concrete with the strength grade of C50, the anti-permeability grade of P12 and the width of limiting crack development is not more than 0.2 mm;

(2) the pipe piece is required to meet the requirements of strength and crack resistance during use, the maximum crack width is not more than 0.2mm, and the leaked cracks and the dry cracks with the crack width more than 0.2mm are subjected to plugging treatment in time;

(3) the completeness of a sealing gasket groove and an embedded joint groove is ensured before the duct piece is assembled;

(4) and (3) performing leak detection test on 1 block of the spot check of every 50 ring pipe pieces, wherein the test standard is as follows: maintaining the water pressure of 0.8Mpa for 3 hours, and ensuring the water seepage depth to be not more than 5 cm;

5.1.2 Lining external grouting waterproof

An annular gap exists between the lining segment and the natural soil body, and the gap is filled through synchronous grouting and secondary grouting to form a peripheral waterproof layer. The synchronous grouting adopts single-fluid slurry, and the secondary grouting adopts cement slurry or double-fluid slurry. In order to reduce the hardening shrinkage of the slurry material, a certain amount of micro-expanding agent is added into the grouting material; the grouting pressure is 0.1-0.2Mpa higher than the water-soil pressure of the driving surface, and the grouting pressure can be timely adjusted according to the stratum characteristics and the water pressure in the construction process, but the following requirements are met: (1) the pressure is larger than the water and soil pressure of the excavation surface; (2) the ground can not be enabled to have larger uplift of less than 10mm, and can not be enabled to have larger settlement of less than 30 mm; (3) the segment can not be dislocated and deformed due to local compression; (4) the slurry cannot be leaked from the segment space or the shield machine and the segment frequently or largely.

5.1.3 Lining joint water proofing

The lining joint waterproof structure comprises an elastic sealing gasket, a water-swelling rubber sealing gasket, a sponge rubber gasket on the outermost side and an inner side caulking joint; the elastic sealing gasket ensures the waterproof effect through the compression of the sealing gasket; the water-swelling rubber sealing gasket can improve the contact stress through water absorption swelling to play a waterproof role and is a second waterproof line of the duct piece; the sponge rubber pad is arranged on the outermost side of the circular seam and the longitudinal seam, so that silt is prevented from entering the groove of the elastic sealing gasket, synchronous grouting slurry is prevented from flowing through the seam of the duct piece, and shield tail sealing grease is saved.

5.2 segment seam Water proofing

The waterproof structure of the duct piece joint mainly comprises an elastic sealing gasket and a water-swelling sealing gasket, and joints are embedded on the inner sides of the joints. The distance between the inner edge of the rubber plate and the circular seam groove edge of the duct piece is 5mm, the outer edge of the rubber plate is arranged on the groove edge of the circular seam water-swelling sealing gasket, and a hole R55 is reserved at the bolt hole.

The joint of the duct piece is waterproof at the corner of the reinforced elastic sealing gasket, and a self-adhesive rubber sheet is required to be coated at the outer corner of the sealing gasket;

5.3 construction method and measures

The method is characterized in that operators are required to prepare waterproof raw materials, coatings and mounting tools before the waterproof material of the duct piece is mounted, the waterproof mounting area of the duct piece is cleaned, the mounting area is ensured to be free of sundries and floating ash, a sealing gasket part is adhered to the duct piece by a blast burner drying process if necessary, and the waterproof material can be mounted after the duct piece with quality defects is required to be repaired to be qualified.

(1) Sticking of ethylene propylene diene monomer elastic sealing gasket

The adhesive of the elastic rubber sealing gasket is a single-component neoprene-phenolic adhesive.

The requirement of coating the binder: the waterproof material agent for the bonding shield segment is uniformly coated on the bonding surface of the elastic rubber sealing gasket and the surface of the segment sealing groove, after the bonding agent is cooled for 15min, the time for installing the waterproof material can be properly adjusted according to the external actual temperature condition, and the time card control standard is as follows: when the adhesive is not sticky, the waterproof material can be installed.

The installation method comprises the following steps: when the water stop strip is sleeved in the duct piece reserved groove, the outer edge of the water stop strip is uniformly close to the outer arc edge of the duct piece reserved groove, the corner is fixed when the water stop strip is sleeved, then the water stop strip is pushed and pressed to the two sides of the corner, the wood hammer is used for continuously knocking, and then the installation effect, especially the installation quality of 4 corner positions, is checked.

Quality standard: the elastic rubber sealing gasket after being pasted is correct in installation position, firm in pasting, smooth and tight, and free of bulging, overlong and notch phenomena, and the sealing gaskets at the four corners of the duct piece are free of shoulder rising and shoulder collapse phenomena. The pipe piece is not sent to the underground for assembly in 12h of sticking and installing the sealing gasket.

(2) Adhesion of polyurethane water-swelling rubber sealing gasket

The polyurethane water-swellable rubber sealing gasket adhesive is a single-component neoprene-phenolic adhesive.

The requirement of coating the binder: uniformly coating the adhesive on the adhesive surface of the force transmission gasket and the concrete surface at the corresponding position of the duct piece, cooling the adhesive for 15min, and properly adjusting the time for installing the waterproof material according to the external actual temperature condition, wherein the time card control standard is as follows: when the adhesive is not sticky, the waterproof material can be installed.

The installation method comprises the following steps: the longitudinal seam liner is pasted along the inner edge of the water retaining groove, a piece is pasted on the same side of each segment, and a hole is reserved at the circumferential screw hole. The circumferential force transfer liner is pasted on the ring surface of the back jack, the circumferential seam force transfer liner is pasted along the inner edge of the caulking groove, one top sealing block is pasted, 4 other pipe pieces are pasted, and a hole is reserved at the longitudinal bolt hole.

Quality standard: the surface of the force transfer liner after being pasted is smooth, and the phenomena of degumming, edge warping, deflection and the like can not occur.

(3) Adhesion of neoprene sponge strip

The adhesive of the sponge strip is a single-component neoprene-phenolic aldehyde adhesive.

The requirement of coating the binder: the adhesive is uniformly coated on the adhesive surface of the sponge strip and the surface of the duct piece concrete at the corresponding position, and the installation time of the sponge strip is also controlled by adopting the application method of the waterproof coating.

The installation method comprises the following steps: the sponge strip connector is arranged on the small mileage side of the duct piece, the connector form adopts 45-degree oblique crossing, and the connector gap is required to be tightly attached. And after the installation is finished, the installation effect, particularly the installation quality of 4 corner positions, is checked by using a wooden hammer for continuous knocking.

Quality standard: the sponge strip after being pasted has accurate installation position, firm pasting, smoothness and tightness, and can not generate phenomena of degumming, edge warping, deflection and the like.

In the construction process, if water leakage occurs, the method can perform corresponding treatment:

in the first case: open cut section water leakage treatment measures:

first, the reason of water leakage in the open cut section

1 self-waterproof structure has defects

On the one hand, the concrete used for construction is mass concrete, and a large amount of hydration heat is released in the process of setting and hardening. Under the combined action of the difference of external temperature, humidity and the like and the heat generated by the concrete, the concrete shrinks and deforms, then cracks are generated, and when the cracks expand to a certain degree, water leakage can occur. On the other hand, the composite lining wall concrete is restrained by the wall body of the early enclosure structure in the hardening process, the trend and the width of cracks of the concrete structure are directly influenced, and the concrete structure is cracked due to the difference of the construction sequence of the concrete of the main structure, so that the self-waterproofing of the structure is caused to have defects.

2 the outer wrapping water is not good

The waterproof design of the open cut section of construction is full-wrapping waterproof, the bottom plate adopts self-adhesive waterproof coiled materials, the side wall adopts self-adhesive waterproof coiled materials, the top plate adopts self-adhesive waterproof coiled materials and waterproof coating materials, but water seepage channels are caused due to the reasons of not tight lapping and sticking of the coiled materials, and the like, so that water seepage is generated in the structure.

Reason for construction

In the construction process of concrete, because the construction vibration is not compact or not in place, the surface of the concrete inside leaks water or has the phenomena of honeycombs, pitted surfaces and rib leakage.

Second, water leakage treatment measures

Once the structure leaks, the waterproof and waterproof layer-wrapped exterior protection structure is proved to have defects certainly, but cannot be processed, and the leakage problem can be solved only by repairing the defects of the structural concrete. The scheme takes the defects of grouting plugging structure concrete as a main means. The defect of waterproof construction is made up through repairing the concrete, and the problem of water leakage is solved.

1 leak site determination

In the open cut section, water seepage positions can be generally and directly observed, and the main seepage positions are construction joints, cracks, induced joints and the like. The water seepage parts are required to be treated comprehensively to achieve the effect of plugging.

2 treatment method

First point leakage

The phenomenon of spot leakage can be classified as a spot or a crack of less than 5 mm. Drilling a hole at the center of the point or the crack, wherein the hole diameter is 10mm, the depth is 6cm, and grouting is carried out after high-pressure clean water washing. The grouting adopts needle type grouting to inject epoxy resin, firstly a grouting needle head is inserted into a built grouting hole, a certain gap is formed between a grouting pipe nozzle and the bottom of the hole, then the grouting needle head is screwed down, the needle head is firmly led in and out of the grouting hole, an orifice and a grouting pipe are fixed by adopting leakage-stopping powder, cracks on two sides are also blocked by adopting the leakage-stopping powder, and grooving treatment is carried out if the effect is not good.

The seepage of the surface of the stone

The surface seepage is formed by point seepage and intensive, for example, the area with the diameter less than 5cm, each procedure can be processed according to the point seepage, then the seepage surface is chiseled to 3cm, the leakage-stopping powder is coated after cleaning, and finally the sealing is carried out by waterproof mortar.

The surface seepage area is larger than 5cm, the base surface is chiseled 5 or 6cm deep, the exposed reinforcing steel bars are cleaned and brushed, and the ring direction is slightly deepened by 2cm, so that water can be conveniently stopped.

Firstly, three steps of coating leakage-blocking powder on a base surface are carried out, the blending consistency of the leakage-blocking powder is determined according to the humidity of the base surface, if the effect of individual points is not good, the leakage-blocking powder can be used for post-supplementing, and the thickness is only 5-15 mm.

Secondly, brushing and brushing the double-component polyurethane coating by 1mm, wherein before brushing, a base surface needs to be air-dried, and 2cm of mortar binding sites are reserved for brushing and brushing the double-component polyurethane coating;

and thirdly, sealing the waterproof mortar.

Leakage from cracks and construction joints

Process flow

Presetting grouting holes → drilling U-shaped grooves → cleaning the base face → flushing the grouting holes → embedding grouting pipes → sealing the leakage-stopping powder covers → grouting → sealing the grouting pipes → recovering the base face.

Secondly, construction process and requirements are as follows:

a. preset grouting hole

According to the formation condition of the crack, the crack is generally a through crack formed by a vertical wall surface, and a grouting hole is arranged and is ensured to be arranged on the crack. And adopting an impact drill with the phi of 10mm to impact and form holes, wherein the depth is 10cm, and the distance is 20 cm. The pore-forming is vertical to the wall surface by taking the crack as the center, and one pore-forming is additionally arranged at the position of the closing-in opening at the two ends of the crack at the interval of 5cm respectively.

b. Chisel U-shaped groove

And after the closing positions of the two ends of the crack are determined, extending for 15cm to be a groove cutting position. In order to ensure the integrity of the groove, firstly, a steel slice is used for cutting a boundary (turning in a straight line) to be 1cm deep and 2-5cm wide, a U-shaped groove is cut along the cutting boundary along a crack until the main rib is exposed, and the depth principle is that a reinforcing steel bar protective layer, the diameter of the main rib and 1cm are used for filling a space, and generally can reach 7 cm.

c. Basal plane cleaning

The cleaning degree of the base surface is the key of the combination effect of the leakage-blocking powder and the base surface, the base surface must be brushed clean by clear water and a steel brush, and impurities such as dust, a scum loose layer and the like are not allowed.

d. Flushing grouting hole

The grouting needle is buried at a depth of 2-3 cm from the base surface, and can be washed by high-pressure water in a grouting pipe penetrating into a hole for several times, and impurities cannot be left in the hole.

e. Embedded grouting pipe

A little space is left in the grouting pipe embedded hole to facilitate the injection of the grout; the orifice is sealed and fixed by the leakage-stopping powder.

f. Leakage-stopping powder cover

The sealing surface of the plugging powder is sealed from one end of the crack to the other end, the materials are uniformly stirred, the time is properly controlled, and the sealing surface is closely combined with the grouting pipe. The water can not be underground water or seeped water from cracks, and tap water is necessary. The operation of powder leakage stoppage is from two sides of the groove to the middle, from the light leakage part to the serious leakage part. The operation is carried out in three layers, wherein the thickness of the first layer is determined according to the principle of water stopping and the size of water seepage, the thickness of the second layer and the thickness of the third layer are 2 cm-3 cm, the surface of each layer is finished by hand to be smooth, without bee holes and pitted surface, and the water spraying and surface collecting are not allowed;

g. grouting

Grouting is carried out after the sealing surface of the plugging powder every other day so as to observe the effect after the sealing surface, and reworking is needed if side seepage exists until the whole sealing surface is not seeped.

Before grouting, pressure test grout inspection is carried out, wherein the pressure test has four purposes of dredging cracks and cleaning sundries in the cracks; checking the penetration condition of the crack; checking whether the sealing layer has a weak point broken by the mud jacking; and judging the grouting flow and the approximate saturation time. The pressure of the pressure test is generally below 0.3MPa, and detailed records are made for analysis and judgment during grouting.

h. Grouting operation method

When no abnormity occurs after pressure test, grouting can be carried out. The grouting adopts a miniature electric high-pressure grouting machine (BZ-518) for grouting, the grouting is started from the first grouting pipe (No. 1) at the bottom end of the crack, when the crack is wider (more than 0.3mm), the grouting pressure is adjusted to be 0.3-0.5 MPa, and when the crack is less than 0.3mm, the pressure can be properly increased by about 0.5 MPa. When the adjacent hole (No. 2) is discharged, the No. 1 hole plastic pipe is cut off from a position which is about 5cm away from the root part, then the plastic pipe is folded reversely and tightened by a binding wire, and then the No. 2 hole is used for grouting. And (3) discharging a slurry hole from bottom to top, closing the hole until the hole at the top end of the crack is blocked, and then continuously stabilizing the pressure for 3min until the whole crack is full of slurry.

After construction is finished, the tool is immediately cleaned by acetone so as to prevent the grout from being unable to be removed after being cured.

Water leakage treatment measure for shield segment in second condition

First, shield the inside water leakage reason of section

1 tunnel segment leakage phenomenon and reason analysis

The inside pipe sheet ring longitudinal joint, section of jurisdiction hole for hoist, shield tunnel and contact channel seam and the portal of dividing into of the left and right sides line tunnel of tunnelling completion all appear the seepage of different degree, and the seepage condition can divide into following several kinds basically:

(1) the surface of the segment at the joint is wet-soaked, and the leakage is the main form of leakage of the whole tunnel;

(2) the leakage or line flow occurs at the seams of the pipe pieces, and the leakage mode is less in the whole interval tunnel;

(3) the segment hoisting hole has leakage;

(4) the pipe piece is damaged and leaks, and no leakage is caused by damage in the whole tunnel;

(5) the shield tunnel leaks from the joints of the communication channel and the tunnel portal.

Through observation and repair construction analysis to tunnel segment seam leakage point, we have summarized the following several for the main reason of segment seam leakage:

(1) in the segment production process, the groove part concrete provided with the sealing gasket is not compact and has the defects of bubbles, air bubbles and the like, and after the segment assembly is completed, water flows in from the bubbles and the air bubble holes by bypassing the sealing gasket.

(2) Because the sealing gasket is poor in sticking quality or is directly put into the well for assembly after the sealing gasket is stuck, the sealing gasket partially falls off in the assembly process, and the sealing gasket between two pipe pieces is not tightly extruded, so that water leakage at the position is caused.

(3) In the assembling process, the pipe pieces collide to make the water stop strip fall off or break, so that the sealing gasket does not form a closed waterproof ring.

(4) After the duct piece is separated from the shield tail, the duct piece dislocation amount is larger than the maximum design value by 10mm due to the upward floating of the duct piece, and the effective contact surface is insufficient due to the staggered sealing gasket between two adjacent duct pieces, so that the water leakage of the duct piece is caused.

(5) The pipe piece back lining slip casting is not full, and the water pressure of local seam department is too big, makes the sealed pad compaction produce the seepage in the weak place.

Second, waterproof leaking stoppage construction method

(1) Leakage of the duct piece spot-mounting part: injecting modified epoxy resin slurry by adopting a pressure grouting method, and sealing the epoxy resin cement gaps;

(2) and (3) duct piece joint leakage: pouring superfine cement paste and modified epoxy resin paste by adopting a pressure grouting method, and sealing the epoxy resin paste gaps;

(3) and (3) duct piece crack leakage: the modified epoxy resin slurry is poured by adopting a pressure grouting method, and the epoxy resin cement concrete is subjected to external sealing treatment.

The construction process flow comprises the following steps:

(1) leakage at the spot-mounting part of the duct piece: treating a construction base surface → establishing a pressure grouting system → pouring modified epoxy slurry → relieving a convex plane part of the grouting system → establishing a modified epoxy cement sealant → cleaning the construction base surface → acceptance;

(2) and (3) segment joint leakage: cleaning a seam → treating a construction base surface → establishing a pressure grouting system → injecting superfine cement paste under pressure → removing a convex plane part of the grouting system → constructing a modified epoxy cement sealant → cleaning a treatment base surface → acceptance;

(3) and (3) duct piece crack leakage: chemically treating construction base surface → drilling, embedding nozzle → building high-strength pressure grouting system → sealing seam → pressure pouring modified epoxy resin grout → removing grouting convex plane part → chemically treating concrete surface → constructing epoxy cement sealant → repairing decorative surface → cleaning site → checking and accepting.

Third, leakage position plugging measure

1 pipe piece circular seam and longitudinal seam leakage treatment

(1) Floating mud and sludge in the annular gap and the longitudinal gap are cleaned by a steel wire brush;

(2) and (4) checking the leakage position, drilling termination holes at two ends of the leakage position, wherein the hole diameter is 0.6cm, and the hole depth reaches the position of the segment sealing pad.

(3) Pressing epoxy emulsion waterproof daub (TN glue) in the hole, and sealing the stop hole;

(4) grouting holes are distributed on the abutted seams at a distance of 35cm, 8mm aluminum pipes are inserted, the embedding depth of the aluminum pipes is 20cm, and the pipes are embedded by adopting latex neoprene latex cement mortar for sealing the abutted seams;

(5) injecting modified epoxy chemical grouting liquid, sequentially grouting at the grouting pressure of 0.4-0.5 MPa, and closing the pipe after the pressure is reached to be solidified.

(6) And (4) after the closed pipe is solidified for 8-12 hours, checking the orifice pipe, and if the orifice pipe is not full, repeatedly grouting for two or more times to ensure grouting quality.

(7) And after the condensation, the aluminum pipe is removed for seam surface modification treatment so as to ensure the quality and appearance requirements of the pipe piece structure.

2 repair measure for water leakage at pipe piece jumping block

(1) Clearing the jumping blocks and loose concrete fragments, searching leakage positions and drilling holes;

(2) embedding an aluminum pipe with the diameter of 8mm after drilling, embedding the aluminum pipe with the depth of 20cm, and sealing the embedded pipe by adopting LB-7 neoprene latex cement mortar;

(3) grouting by adopting modified epoxy grouting liquid, wherein the grouting pressure is 0.4-0.5 MPa, and closing the pipe after the pressure is reached for solidification;

(4) checking the bubble tube at the orifice after 8-12 hours of coagulation, and performing secondary or multiple times of grouting when the bubble tube is not full;

(5) and (3) detaching the pipe after 3-7 days of solidification, removing the sealing cement protruding from the embedding and filling, filling the concrete to a base surface by using LB-21 epoxy cement, and treating the base surface to ensure that the appearance of the pipe piece meets the requirement.

3 bolt hole and hoisting hole leakage repairing measure

(1) The nut of the bolt hole is loosened;

(2) removing floating mud, mud scale and rust in the bolt hole;

(3) closing an outlet at one end by using chloroprene latex polymer cement mortar, and inserting a small aluminum pipe (phi 8 mm) from an outlet at the other end to close by using chloroprene latex polymer cement mortar;

(4) drilling termination holes with the aperture of 12mm and the depth of the holes reaching the segment sealing gasket at two sides of the corresponding abutted seam corresponding to the bolts;

(5) grouting by adopting modified epoxy chemical grouting liquid, wherein the grouting pressure is 0.3-0.4 MPa;

(6) checking the bubble tube at the orifice after 8-12 hours of coagulation, and performing secondary or multiple times of grouting when the bubble tube is not full;

(7) removing the pipe after 5-7 days of coagulation, removing the sealing cement protruding from the embedding and filling, filling the concrete with LB-21 epoxy cement mortar until the basal plane is coated with LB-7 neoprene latex cement mortar, installing a butt joint screw inspection cap, and replacing a rubber ring (adopting a chlorinated polyethylene rubber pad);

(8) repairing the segment at the position of the bolt hole to ensure the quality and appearance requirements of the segment structure;

(9) and (3) plugging the hoisting hole by adopting double-speed cement sand ice, screwing a reverse material plug after plugging, and cleaning up residual cement paste of the pipe joint piece.

4 shield tunnel interface leakage repair measure

The water seepage of the shield tunnel interface is analyzed to be caused by the reasons that concrete is not compact, construction joints are not well treated, a waterproof layer is locally broken and damaged, and the like, a water source is mainly bedrock fracture water of a tunnel body penetrating through surrounding rock, modified epoxy chemical grouting liquid is adopted for grouting cracks and concrete non-compact parts aiming at the phenomenon, and a quick-setting micro-expansion cement quick sealing method is used for reinforcing and mending leakage.

The process comprises the following steps:

(1) the joint construction joints and the positions of the crack leakage water were carefully observed and marked with symbols, and then V-shaped grouting slots of about 6cm depth and 5cm width were chiseled along the leakage joints.

(2) Cleaning loose sludge on the inner surface of the gap, and then washing the base surface by using a steel wire brush until the plate gap is completely exposed, and waiting for the next procedure for construction.

(3) Arranging three grouting nozzles in the cleaned V-shaped groove, wherein each meter of the aluminum pipe is provided with an aluminum pipe with the diameter of 8mm, and then forcibly plugging the grouting grooves with quick-setting micro-expansion cement paste (0.5: 1).

(4) Connecting a grouting machine with a pre-buried grouting nozzle, slowly injecting the slurry modified epoxy chemical grouting material into a container of the grouting machine, slowly pressurizing by hand, controlling the grouting pressure within 0.4MPa, and quickly winding the grouting pipe into an S shape to be tied to prevent the slurry from flowing out after grouting is finished. The perps should be poured from below and above, with no interruption in the middle.

(5) After grouting for 24 hours, the grouting nozzle can be pulled out, and the grouting amount is determined by the following steps of 1: 2.5 leveling and restoring cement mortar to ensure the appearance of the joint.

The effects of the present invention obtained by adopting the above-defined technique are shown in table 1:

table 1 table of results of each inspection item of the present invention

Claims (7)

1. A river-crossing tunnel engineering waterproof construction method is characterized by comprising waterproof of a main structure and an auxiliary structure of an open excavation section, the waterproof of a construction joint, a deformation joint, a pile head, a wall-penetrating pipe box, a dewatering well, a lattice column and the like, wherein the main structure and the auxiliary structure of the open excavation section comprise a bottom plate, a side wall and a top plate, and a drainage prevention mode combining a flexible waterproof layer and a reinforced concrete self-waterproof layer is adopted; the construction joint, deformation joint, pile head, wall-penetrating pipe box, precipitation well, lattice column and the like are waterproof assisted by a water stop component, the construction joint is arranged at the construction section and the layering position, and the deformation joint is arranged at the construction section position.

2. The river-crossing tunnel engineering waterproof construction method according to claim 1, wherein the waterproof construction process of the bottom plate, the side wall and the top plate comprises the following steps: concrete base cushion press polishing → base surface cleaning → chamfering treatment of the female corner part and the male corner part → laying of the waterproof coiled material reinforcing layer of the female corner part and the male corner part → laying of the waterproof coiled material in a large area → inspection and acceptance → fine stone concrete protection layer → construction of a structural layer.

3. The river-crossing tunnel engineering waterproof construction method according to claim 2, wherein the waterproof construction process of the bottom plate, the side wall and the top plate comprises the following steps:

1) concrete base cushion press polish

2) Base surface treatment

a. The surfaces of the concrete base cushion layer (1) and the enclosure structure (2) are not required to have open water, and when the surface of the concrete base cushion layer (1) is free of open water, a leveling layer is applied to the part of the enclosure structure (2) with the surface flatness not meeting the design requirement;

b. when the crack width of the concrete base cushion layer (1) is more than or equal to 1.5mm, embedding and filling, and embedding and filling cement mortar or bentonite waterproof slurry on the V-shaped groove plane of the joint chiseling;

c. the side wall connected with the bottom plate of the concrete base cushion layer (1) adopts 1: 2.5 leveling cement mortar;

d. leveling the surface of the leveling layer;

(3) all the internal and external corner parts adopt 1: 2.5, preparing a 50x50mm mortar chamfer angle (3) by using the cement mortar;

(4) self-adhesive waterproof coiled material laying

a. Spreading a waterproof coiled material, arranging the coiled material at the position of a negative corner, a positive corner and a position with a joint with an upward PE film, and paving to obtain a waterproof coiled material reinforcing layer (4);

b. then, the waterproof coiled material is unfolded and placed at a position needing to be made into a waterproof part, the coiled material is fixed on the base layer by a cement nail, the bonding surface faces outwards to uncover the isolating film at the bonding side of the self-adhesive coiled material fixed on the base layer, the isolating film is rolled and paved while being torn, the self-adhesive coiled material is bonded with the previous coiled material, after the bonding is finished, the other coiled material is remade according to the method, and the high-molecular self-adhesive film waterproof coiled material (5) is paved in a large area;

c. rolling: sequentially compacting the whole surface of the adhered high-molecular self-adhesive film waterproof coiled material (5) by a compression roller, wherein the overlapped part needs to be intensively rolled; applying a rubber hammer to the special-shaped part and the overlapped T-shaped part for striking tightly;

(5) and after the waterproof coiled material is constructed, the inspection and acceptance are qualified, and the construction of the fine aggregate concrete protective layer (6) and the structural layer is carried out.

4. The river-crossing tunnel engineering waterproof construction method according to claim 1, characterized in that a steel plate waterstop (8) is adopted for the construction joint (7), a cement-based permeable crystalline waterproof coating (10) is coated on the structural side of the construction joint, a water-swelling waterstop (9) is arranged on the inner side of the construction joint, the steel plate waterstop (8) is welded on structural steel bars at a fixed interval of 1m, and the waterstop is prevented from lodging when concrete is poured and vibrated; when concrete at the construction joint position is poured and vibrated, the steel plate waterstop is straightened while pouring, so that the steel plate waterstop is prevented from being too large in snake shape and lodging; the concrete at the water stop part is vibrated fully, so that the water stop is tightly occluded with the concrete; and (3) coating cement-based capillary crystalline waterproof materials on the concrete surfaces of the construction joints and the pile heads.

5. The river-crossing tunnel engineering waterproof construction method according to claim 1, characterized in that deformation joints of side walls and bottom plates facing water are firstly paved with a high-molecular self-adhesive film waterproof roll (5), then a back-attached rubber water stop (11) or sealant is arranged for caulking treatment, and finally a two-component polysulfide sealant (12) is adopted for waterproofing; when the back-pasting rubber waterstop (11) is arranged, the water-facing side of the top plate is provided with the double-component polysulfide sealant (12) for embedding and filling to form a waterstop ring; when the sealant is used for caulking treatment, the two-component polysulfide sealant is used.

6. The river-crossing tunnel engineering waterproof construction method according to claim 1, characterized in that the pile head waterproof construction process is as follows:

firstly, before the cushion layer construction, chiseling out the pile head to the designed elevation position, and removing mud, floating slurry, loose broken stones and the like from the exposed pile body part; then adopting a waterproof roll waterproof layer (13) of the pile body at the internal corner part of the pile body and the cushion layer, simultaneously filling 10mm polymer cement-based M10 waterproof mortar at the internal corner part, and treating the pile body and the pile head part by using a cement-based infiltration crystallization waterproof coating (14) with the thickness of 2.0 mm; and a pile body water-swelling water stop strip (15) is arranged at the position of the pile head reinforcing steel bar and the position of the pile body, and the water stop strip surrounds the pile body and the pile reinforcing steel bar.

7. The river-crossing tunnel engineering waterproof construction method according to claim 1, wherein the waterproof construction process of the wall-penetrating pipe, the dewatering well and the like is as follows:

1) wall pipe: welding a steel sheet water stop ring around the pipe wall of the wall penetrating pipe, and arranging sealant at the positions of the water stop ring and the pipe wall in a circumferential direction for sealing; arranging a double-sided self-adhesive waterproof layer at the internal corner part of the joint of the pipe and the structural surface, and embedding and filling the double-sided self-adhesive waterproof layer with sealant to connect the double-sided self-adhesive waterproof layer into a whole;

2) dewatering well: the remaining dewatering well is subjected to water pumping construction continuously by penetrating the bottom plate; for a depressurization well needing to be closed, before the construction of a bottom plate, arranging a steel sleeve outside a well pipe of the depressurization well, arranging a water-stopping steel ring outside the steel sleeve, arranging filling M10 waterproof cement mortar at the joint of the water-stopping steel ring and the sleeve, and plugging the depressurization well after the construction of the bottom plate is finished;

3) lattice column: chiseling the pile head of the lattice column upright column pile to a designed elevation, removing soil floating slurry, loose broken stones and the like of the pile head, and then treating the pile head part with 1.0mm cement-based infiltration crystallization waterproof coating; secondly, bonding the waterproof coiled material of the bottom plate and the pile head part by adopting sealant so as to connect the waterproof coiled material of the bottom plate and the pile head part into a whole; and finally, winding two water-swelling water stop strips on the inner wall and the outer wall of the latticed column within the range of the bottom plate respectively to enhance the water stop performance of the latticed column.

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