CN110984999B - Tunnel shaft construction method - Google Patents

Tunnel shaft construction method Download PDF

Info

Publication number
CN110984999B
CN110984999B CN201911161105.4A CN201911161105A CN110984999B CN 110984999 B CN110984999 B CN 110984999B CN 201911161105 A CN201911161105 A CN 201911161105A CN 110984999 B CN110984999 B CN 110984999B
Authority
CN
China
Prior art keywords
concrete
shaft
construction
well
spraying
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201911161105.4A
Other languages
Chinese (zh)
Other versions
CN110984999A (en
Inventor
何斌
王大为
张海波
黄鑫
何庆姝
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Second Engineering Co Ltd of China Railway 19th Bureau Group Co Ltd
Original Assignee
Second Engineering Co Ltd of China Railway 19th Bureau Group Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Second Engineering Co Ltd of China Railway 19th Bureau Group Co Ltd filed Critical Second Engineering Co Ltd of China Railway 19th Bureau Group Co Ltd
Priority to CN201911161105.4A priority Critical patent/CN110984999B/en
Publication of CN110984999A publication Critical patent/CN110984999A/en
Application granted granted Critical
Publication of CN110984999B publication Critical patent/CN110984999B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21DSHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D1/00Sinking shafts
    • E21D1/08Sinking shafts while moving the lining downwards
    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21DSHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D5/00Lining shafts; Linings therefor
    • E21D5/11Lining shafts; Linings therefor with combinations of different materials, e.g. wood, metal, concrete
    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21DSHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D5/00Lining shafts; Linings therefor
    • E21D5/12Accessories for making shaft linings, e.g. suspended cradles, shutterings

Abstract

A construction method of a tunnel vertical shaft relates to a construction method of a tunnel vertical shaft. The method is mainly designed for solving the problems of low construction speed and the like of the existing tunnel vertical shaft construction method. And excavating and constructing a locking ring on the surface soil section of the vertical shaft well head. And backfilling the well ring wall with concrete to the height of the well mouth. Constructing a wellhead reinforcing section; excavating and constructing the well body by adopting a drilling and blasting method, and carrying out primary support; and after the shaft tunneling and the primary support are finished, performing secondary lining and wall seat construction. And drilling a blast hole, blasting, and grabbing and lifting. And finally, performing primary support of the shaft, spraying concrete, and performing secondary lining and wall seat construction after shaft tunneling and primary support are completed. After the shaft excavation is finished, the vertical drainage pipes are arranged at the water dripping and leaking positions on the surface of the surrounding rock of the shaft for centralized drainage and then the concrete spraying construction is carried out. After the concrete is sprayed, a soft permeable pipe is laid on the surface of the sprayed concrete, and water is discharged into a central drainage ditch of the main tunnel. Its advantage is high construction speed.

Description

Tunnel shaft construction method
The technical field is as follows:
the invention relates to a construction method of a tunnel vertical shaft.
Background art:
in the construction of the existing extra-long tunnel, in order to shorten the construction period, a vertical shaft is arranged in the middle section of the tunnel to increase the working surface. The existing construction method of the tunnel vertical shaft has the problems of low construction speed and overlong single cycle time of each procedure, and the construction progress is influenced because the cycle time of general mechanical construction is 19-22 hours. In addition, the water prevention and drainage measures are poor, and the safety quality in the later period cannot be well guaranteed. According to incomplete statistics, 70% of vertical shafts in every 100 vertical shaft projects at present are subjected to later maintenance due to water leakage prevention and frost heaving in alpine regions, but the later maintenance is particularly difficult, and the construction cost is greatly increased.
The invention content is as follows:
the invention aims to solve the technical problem of providing a tunnel vertical shaft construction method which is high in construction speed, short in single cycle time and good in waterproof and drainage effects.
In order to solve the problems, the invention adopts the following technical scheme;
excavating a vertical shaft wellhead field and a wellhead section;
and after the center of the shaft is calibrated, a shaft opening field is excavated at the periphery of the vertical shaft, so that the construction requirement of the shaft is met.
The well mouth is 1.0m higher than the ground surface, a well ring and a locking ring of a C30 reinforced concrete structure are arranged in the vertical shaft within the range of 5m from the well mouth, and then C15 pieces of stone concrete are backfilled around the well mouth.
Utilize mechanical equipment to excavate shaft well head top soil segment after the well head place levels, excavation depth 4m excavates in two-layer, and every layer excavates the depth 2m, and the first layer is excavated 2m and is carried out the second floor and excavates the construction downwards.
And excavating the shaft mouth section of the vertical shaft to form and cleaning the bottom, and then constructing a locking ring. And erecting reinforcing steel bars of the fore shaft ring, erecting internal and external templates of the fore shaft ring after the reinforcing steel bars are erected, pouring concrete of the fore shaft ring after the templates are erected, and timely curing the concrete after the pouring is finished. And (3) curing the concrete for 7 days, removing the locking ring template when the strength reaches over 75% of the designed strength, then backfilling the walling to the height of the wellhead by adopting C15 pieces of stone concrete layer by layer, wherein the backfilling height is 4m, the backfilling height of each layer is 1m, and the backfilling is completed by four times. And after backfilling is finished, continuously maintaining the backfilled stone concrete and the inner walls of the well ring and the locking ring for 28 days, and performing next construction after the concrete reaches 100% of the designed strength.
When filling rubble concrete around the wellhead, pouring foundations of four derrick column feet and two inclined strut column feet simultaneously, wherein the column foot foundations are of a C30 reinforced concrete structure. And simultaneously maintaining the column base foundation, the vertical shaft locking ring and the backfilled stone concrete.
Constructing a wellhead reinforcing section;
before the construction of a well mouth strengthening section, the installation work of lifting a derrick by a shaft is completed, a head sheave platform of the derrick is provided with a head sheave with the diameter of phi 1m, and a slag unloading platform is arranged above the well mouth.
The excavation of the soil and stones at the reinforcement section of the well mouth adopts the single-process circulation operation of mechanical excavation, manual trimming of excavation contour lines and lining. During excavation, a grabbing head of a central rotary rock grab is used for directly grabbing surface soil stones and placing the surface soil stones into a lifting bucket, a lifting machine lifts the lifting bucket to a wellhead slag unloading platform, the soil stones are unloaded to the surface of the wellhead, the excavation depth of each layer of soil stones is controlled to be 1m, after excavation of each layer of soil stones is completed, an excavation contour line is manually trimmed, and primary support operation is carried out after trimming.
When the primary support of the construction of the reinforcement section of the wellhead is carried out, C25 concrete is sprayed firstly, concrete with the thickness of 4cm is sprayed firstly, then holes are drilled according to the arrangement positions of anchor rods on the well wall, the hole depth is 3m from the original rock of the well wall, after the holes are drilled, a radial hollow grouting anchor rod with the diameter of 25mm is constructed, then a reinforcing mesh is hung, the lap joint of meshes is fixed by the anchor rods, an I16-shaped steel frame is erected close to the primary spraying surface, when the steel frame is accurately in place and connecting steel bars are welded, the concrete is sprayed secondarily immediately, the concrete is sprayed secondarily in a layered mode, each layer is 5-6 cm, the thickness of the concrete reaches 22cm, and the surface of the concrete is smooth after the concrete is sprayed.
Excavating the well body by adopting a drilling and blasting method, and carrying out primary support according to the surrounding rock condition of the shaft;
after the construction of the well mouth reinforcing section is completed, a well mouth disc (namely a well lid) is timely installed at the well mouth, a fixed disc is arranged at a position 5m below the well mouth disc, and a double-layer hanging scaffold is installed below the fixed disc.
From the well mouth strengthening section to the well bottom, the lining structure adopts hollow anchor rods, C25 sprayed concrete, reinforcing mesh and C30 molded concrete, the wall seat lining structure adopts C30 reinforced concrete, the joint of the wall seat and the lining is provided with a reinforced concrete strengthening section, and the wall thickness of the reinforced concrete strengthening section is 40 cm; c30 the molded concrete is the secondary lining, the rest supporting materials are the primary supporting construction, after the shaft is tunneled from top to bottom and the primary supporting is completed, the construction operation of the secondary lining and the wall seat is carried out from bottom to top.
The method comprises the steps of cleaning surrounding rock pumice and dangerous stones around a working face to a tunneling working face, drilling blast holes, charging, warning and blasting, ventilating in time after blasting, cleaning the hanging scaffold and the pumice and the dangerous stones on a well wall after the air quality of the working face is qualified, and then grabbing and lifting. And finally, carrying out primary support of a shaft, spraying concrete with the thickness of 4cm when spraying C25 concrete, then drilling holes by a rock chiseling worker according to the arrangement positions of anchor rods on the well wall, wherein the hole depth is 3m from the well wall original rock, constructing the anchor rods after drilling, hanging a reinforcing mesh, fixing the lap joints of the mesh sheets by the anchor rods, erecting an H =15 grid steel frame close to the primary spraying surface as far as possible, setting no less than 8 positions of saddle or wedge-shaped cushion blocks in a gap, tightly supporting surrounding rocks, carrying out secondary concrete spraying operation immediately after the steel frame is accurately positioned and connecting steel bars are welded, carrying out secondary concrete spraying when spraying concrete, enabling the layer-sprayed concrete to reach the designed thickness (the sprayed concrete thickness is 21cm in total), and ensuring that the net protective layer thickness of the profile steel frame is not less than 2cm, and enabling the surface of the concrete to be smooth after spraying.
And controlling the circulating footage of blasting excavation within 1.0m, drilling blast holes by adopting a rock drill, wherein the hole depth is 1.5-2 m, the hole diameter is 38-42 mm, and the loading of each hole is 0.6-1 kg. During excavation, a smooth blasting technology is adopted to control the surrounding rock overbreak and underbreak, blasting parameters are adjusted at any time according to the crushing condition of the shaft surrounding rock, the single-shot blasting amount is reduced by shortening the length of a blast hole and adopting a delayed blasting mode, and the stability of the surrounding rock is ensured.
The primary support is a combined stress structure consisting of anchor rods, reinforcing mesh, profile steel frames and sprayed concrete.
The rock surface is blown clean from top to bottom by high-pressure air, and the mark nail for controlling the thickness of the sprayed concrete is embedded.
The spraying operation is performed along the well wall from bottom to top in a piling mode, so that the phenomenon that the upper spraying rebound material covers the lower well wall loosely and is not compact, and the instability is caused due to insufficient strength; the depressions are leveled first and then the projections are ejected and joined smoothly.
The spraying operation moves in a spiral circle along the horizontal direction, the spray head is kept as vertical as possible to the sprayed surface, and the distance from the nozzle opening to the sprayed surface is preferably 0.6 m-1.0 m.
And (5) carrying out anchor rod installation operation in time after the concrete is initially sprayed.
The hollow anchor rod grouting adopts a single-liquid grouting pump, the mixed slurry enters the cylinder body through a slurry suction pump and is sent to a grouting pipe to reach a slurry discharge hole at the hollow bottom end of the anchor rod, and the slurry is pressed into a gap between a rock body and a rod body, so that the surrounding rock is reinforced and the bearing capacity of a supporting system is improved.
Grid steel frame and shaped steel frame are in time erected after the shaft is excavated, should spout 4cm concrete earlier before erecting, apply and do radial stock and hang the reinforcing bar net, and the steelframe is close to the primary spray face as far as, if have the space establish ride horse or wedge cushion be no less than 8, push up tight country rock, take one's place and connect the reinforcing bar welding back when the steelframe is accurate, spout concrete to design thickness immediately.
After the shaft is tunneled from top to bottom and the primary support is completely finished, secondary lining and wall seat construction are carried out from bottom to top. Before construction, the procedures of installing a drainage system, paving a waterproof coiled material, installing reinforcing steel bars, installing templates, pouring concrete and the like are carried out. And the lining pouring is carried out from bottom to top by adopting a self-elevating hydraulic slip form process.
During construction, a self-elevating slip form is arranged at the bottom of a well and slides from bottom to top, and meanwhile, concrete is poured by the slip form while steel bars are bound. The sliding lifting of the sliding mould requires symmetrical and uniform blanking, normal construction is carried out layer by layer, one layer is arranged every 30cm, an inserted vibrator is adopted for vibrating, the vibrating direction is often changed, direct vibrating of a sliding rod and a template is avoided, the insertion depth of the vibrator is not more than 50cm in lower-layer concrete, and vibrating is stopped when the template slides. The normal sliding-lifting speed is controlled to be 30cm and the daily sliding-lifting height is controlled to be about 3.6m according to 2 hours at each time interval.
When the mold building lining construction is carried out to the position 1.5m below the wall seat, firstly, the wall seat is excavated and concrete is sprayed, the waterproof coiled material is paved and then steel bars are bound, then the concrete is poured by slip form until the position 1.5m above the wall seat and the total height of the wall seat and the reinforcing section is 4 m.
And when the sliding mould slides to a specified position, the sliding mould is emptied, and then the shaft lifting system is used for dismounting at a wellhead.
After the shaft excavation is finished, the vertical drainage pipes are arranged at the water dripping and leaking positions on the surface of the surrounding rock of the shaft for centralized drainage and then the concrete spraying construction is carried out. After the concrete is sprayed, the soft pervious pipes are vertically paved on the surface of the sprayed concrete, 4 channels are uniformly arranged on the soft pervious pipes along the surface of the sprayed concrete and are fixed by fixing nails, and the whole surface of the soft pervious pipes is wrapped by geotextile to be used as a reverse filter layer before installation so as to prevent silt in the fissure water from blocking the pervious pipes. And (3) completely paving 400 g/square meter geotextile and 1.5mm thick single-sided self-adhesive waterproof coiled materials on the surface of the sprayed concrete, arranging a circumferential plastic blind ditch at the back of the waterproof coiled materials according to design requirements, enabling seepage water to flow into a phi 50 mm soft water permeable pipe connected with the circumferential blind ditch through the circumferential blind ditch, and guiding and discharging the water to a central drainage ditch of a shaft bottom communication channel. A phi 50 mm annular plastic blind ditch is arranged at the top edge of the wall seat and is connected with the soft permeable pipe through a four-way pipe. The waterproof coiled material and the annular plastic blind ditch are applied from bottom to top, and the whole surface of the plastic blind ditch is wrapped by geotextile to be used as a reverse filter layer before installation. And a 1.5mm single-sided self-adhesive waterproof coiled material full-vertical-shaft full-pavement is adopted between the primary support and the secondary lining. The annular construction joint and the settlement joint are provided with a middle-buried water stop. And a circumferential plastic blind ditch is arranged at each wall seat along the longitudinal direction of the vertical shaft, and four symmetrically arranged vertical phi 50 soft permeable pipes are used for discharging running water in the pipe into the lower part of the shaft and finally into a central drainage ditch of the main hole of the tunnel.
The invention has the advantages that: the construction speed is high, the single cycle time is short, the waterproof and drainage effects are good,
geotextile of 400 g/square meter and single-sided self-adhesive waterproof coiled material of 1.5mm thickness are laid through full rings, a circumferential plastic blind ditch is arranged at the back of the waterproof coiled material according to the design requirement, seepage water flows into a phi 50 mm soft water permeable pipe connected with the circumferential blind ditch through the circumferential blind ditch, and the water is guided and discharged to a central drainage ditch of a shaft bottom communication channel. The problems of leakage prevention of drainage water and frost heaving in high and cold areas can be effectively solved.
The specific implementation mode is as follows:
excavating a vertical shaft wellhead field and a wellhead section;
and after the center of the shaft is calibrated, a shaft opening field is excavated at the periphery of the vertical shaft, so that the construction requirement of the shaft is met.
The well mouth is 1.0m higher than the ground surface, a well ring and a locking ring of a C30 reinforced concrete structure are arranged in the vertical shaft within the range of 5m from the well mouth, and then C15 pieces of stone concrete are backfilled around the well mouth.
Utilize mechanical equipment to excavate shaft well head top soil segment after the well head place levels, excavation depth 4m excavates in two-layer, and every layer excavates the depth 2m, and the first layer is excavated 2m and is carried out the second floor and excavates the construction downwards.
And excavating the shaft mouth section of the vertical shaft to form and cleaning the bottom, and then constructing a locking ring. And erecting reinforcing steel bars of the fore shaft ring, erecting internal and external templates of the fore shaft ring after the reinforcing steel bars are erected, pouring concrete of the fore shaft ring after the templates are erected, and timely curing the concrete after the pouring is finished. And (3) curing the concrete for 7 days, removing the locking ring template when the strength reaches over 75% of the designed strength, then backfilling the walling to the height of the wellhead by adopting C15 pieces of stone concrete layer by layer, wherein the backfilling height is 4m, the backfilling height of each layer is 1m, and the backfilling is completed by four times. And after backfilling is finished, continuously maintaining the backfilled stone concrete and the inner walls of the well ring and the locking ring for 28 days, and performing next construction after the concrete reaches 100% of the designed strength.
When filling rubble concrete around the wellhead, pouring foundations of four derrick column feet and two inclined strut column feet simultaneously, wherein the column foot foundations are of a C30 reinforced concrete structure. And simultaneously maintaining the column base foundation, the vertical shaft locking ring and the backfilled stone concrete.
Constructing a wellhead reinforcing section;
before the construction of a well mouth strengthening section, the installation work of lifting a derrick by a shaft is completed, a head sheave platform of the derrick is provided with a head sheave with the diameter of phi 1m, and a slag unloading platform is arranged above the well mouth.
The excavation of the soil and stones at the reinforcement section of the well mouth adopts the single-process circulation operation of mechanical excavation, manual trimming of excavation contour lines and lining. During excavation, a grabbing head of a central rotary rock grab is used for directly grabbing surface soil stones and placing the surface soil stones into a lifting bucket, a lifting machine lifts the lifting bucket to a wellhead slag unloading platform, the soil stones are unloaded to the surface of the wellhead, the excavation depth of each layer of soil stones is controlled to be 1m, after excavation of each layer of soil stones is completed, an excavation contour line is manually trimmed, and primary support operation is carried out after trimming.
When the primary support of the construction of the reinforcement section of the wellhead is carried out, C25 concrete is sprayed firstly, concrete with the thickness of 4cm is sprayed firstly, then holes are drilled according to the arrangement positions of anchor rods on the well wall, the hole depth is 3m from the original rock of the well wall, after the holes are drilled, a radial hollow grouting anchor rod with the diameter of 25mm is constructed, then a reinforcing mesh is hung, the lap joint of meshes is fixed by the anchor rods, an I16-shaped steel frame is erected close to the primary spraying surface, when the steel frame is accurately in place and connecting steel bars are welded, the concrete is sprayed secondarily immediately, the concrete is sprayed secondarily in a layered mode, each layer is 5-6 cm, the thickness of the concrete reaches 22cm, and the surface of the concrete is smooth after the concrete is sprayed.
Excavating the well body by adopting a drilling and blasting method, and carrying out primary support according to the surrounding rock condition of the shaft;
after the construction of the well mouth reinforcing section is completed, a well mouth disc (namely a well lid) is timely installed at the well mouth, a fixed disc is arranged at a position 5m below the well mouth disc, and a double-layer hanging scaffold is installed below the fixed disc.
From the well mouth strengthening section to the well bottom, the lining structure adopts hollow anchor rods, C25 sprayed concrete, reinforcing mesh and C30 molded concrete, the wall seat lining structure adopts C30 reinforced concrete, the joint of the wall seat and the lining is provided with a reinforced concrete strengthening section, and the wall thickness of the reinforced concrete strengthening section is 40 cm; c30 the molded concrete is the secondary lining, the rest supporting materials are the primary supporting construction, after the shaft is tunneled from top to bottom and the primary supporting is completed, the construction operation of the secondary lining and the wall seat is carried out from bottom to top.
The method comprises the steps of cleaning surrounding rock pumice and dangerous stones around a working face to a tunneling working face, drilling blast holes, charging, warning and blasting, ventilating in time after blasting, cleaning the hanging scaffold and the pumice and the dangerous stones on a well wall after the air quality of the working face is qualified, and then grabbing and lifting. And finally, carrying out primary support of a shaft, spraying concrete with the thickness of 4cm when spraying C25 concrete, then drilling holes by a rock chiseling worker according to the arrangement positions of anchor rods on the well wall, wherein the hole depth is 3m from the well wall original rock, constructing the anchor rods after drilling, hanging a reinforcing mesh, fixing the lap joints of the mesh sheets by the anchor rods, erecting an H =15 grid steel frame close to the primary spraying surface as far as possible, setting no less than 8 positions of saddle or wedge-shaped cushion blocks in a gap, tightly supporting surrounding rocks, carrying out secondary concrete spraying operation immediately after the steel frame is accurately positioned and connecting steel bars are welded, carrying out secondary concrete spraying when spraying concrete, enabling the layer-sprayed concrete to reach the designed thickness (the sprayed concrete thickness is 21cm in total), and ensuring that the net protective layer thickness of the profile steel frame is not less than 2cm, and enabling the surface of the concrete to be smooth after spraying.
And controlling the circulating footage of blasting excavation within 1.0m, drilling blast holes by adopting a rock drill, wherein the hole depth is 1.5-2 m, the hole diameter is 38-42 mm, and the loading of each hole is 0.6-1 kg. During excavation, a smooth blasting technology is adopted to control the surrounding rock overbreak and underbreak, blasting parameters are adjusted at any time according to the crushing condition of the shaft surrounding rock, the single-shot blasting amount is reduced by shortening the length of a blast hole and adopting a delayed blasting mode, and the stability of the surrounding rock is ensured.
The primary support is a combined stress structure consisting of anchor rods, reinforcing mesh, profile steel frames and sprayed concrete.
The rock surface is blown clean from top to bottom by high-pressure air, and the mark nail for controlling the thickness of the sprayed concrete is embedded.
The spraying operation is performed along the well wall from bottom to top in a piling mode, so that the phenomenon that the upper spraying rebound material covers the lower well wall loosely and is not compact, and the instability is caused due to insufficient strength; the depressions are leveled first and then the projections are ejected and joined smoothly.
The spraying operation moves in a spiral circle along the horizontal direction, the spray head is kept as vertical as possible to the sprayed surface, and the distance from the nozzle opening to the sprayed surface is preferably 0.6 m-1.0 m.
And (5) carrying out anchor rod installation operation in time after the concrete is initially sprayed.
The hollow anchor rod grouting adopts a single-liquid grouting pump, the mixed slurry enters the cylinder body through a slurry suction pump and is sent to a grouting pipe to reach a slurry discharge hole at the hollow bottom end of the anchor rod, and the slurry is pressed into a gap between a rock body and a rod body, so that the surrounding rock is reinforced and the bearing capacity of a supporting system is improved.
Grid steel frame and shaped steel frame are in time erected after the shaft is excavated, should spout 4cm concrete earlier before erecting, apply and do radial stock and hang the reinforcing bar net, and the steelframe is close to the primary spray face as far as, if have the space establish ride horse or wedge cushion be no less than 8, push up tight country rock, take one's place and connect the reinforcing bar welding back when the steelframe is accurate, spout concrete to design thickness immediately.
After the shaft is tunneled from top to bottom and the primary support is completely finished, secondary lining and wall seat construction are carried out from bottom to top. Before construction, the procedures of installing a drainage system, paving a waterproof coiled material, installing reinforcing steel bars, installing templates, pouring concrete and the like are carried out. And the lining pouring is carried out from bottom to top by adopting a self-elevating hydraulic slip form process.
During construction, a self-elevating slip form is arranged at the bottom of a well and slides from bottom to top, and meanwhile, concrete is poured by the slip form while steel bars are bound. The sliding lifting of the sliding mould requires symmetrical and uniform blanking, normal construction is carried out layer by layer, one layer is arranged every 30cm, an inserted vibrator is adopted for vibrating, the vibrating direction is often changed, direct vibrating of a sliding rod and a template is avoided, the insertion depth of the vibrator is not more than 50cm in lower-layer concrete, and vibrating is stopped when the template slides. The normal sliding-lifting speed is controlled to be 30cm and the daily sliding-lifting height is controlled to be about 3.6m according to 2 hours at each time interval.
When the mold building lining construction is carried out to the position 1.5m below the wall seat, firstly, the wall seat is excavated and concrete is sprayed, the waterproof coiled material is paved and then steel bars are bound, then the concrete is poured by slip form until the position 1.5m above the wall seat and the total height of the wall seat and the reinforcing section is 4 m.
And when the sliding mould slides to a specified position, the sliding mould is emptied, and then the shaft lifting system is used for dismounting at a wellhead.
After the shaft excavation is finished, the vertical drainage pipes are arranged at the water dripping and leaking positions on the surface of the surrounding rock of the shaft for centralized drainage and then the concrete spraying construction is carried out. After the concrete is sprayed, the soft pervious pipes are vertically paved on the surface of the sprayed concrete, 4 channels are uniformly arranged on the soft pervious pipes along the surface of the sprayed concrete and are fixed by fixing nails, and the whole surface of the soft pervious pipes is wrapped by geotextile to be used as a reverse filter layer before installation so as to prevent silt in the fissure water from blocking the pervious pipes. And (3) completely paving 400 g/square meter geotextile and 1.5mm thick single-sided self-adhesive waterproof coiled materials on the surface of the sprayed concrete, arranging a circumferential plastic blind ditch at the back of the waterproof coiled materials according to design requirements, enabling seepage water to flow into a phi 50 mm soft water permeable pipe connected with the circumferential blind ditch through the circumferential blind ditch, and guiding and discharging the water to a central drainage ditch of a shaft bottom communication channel. A phi 50 mm annular plastic blind ditch is arranged at the top edge of the wall seat and is connected with the soft permeable pipe through a four-way pipe. The waterproof coiled material and the annular plastic blind ditch are applied from bottom to top, and the whole surface of the plastic blind ditch is wrapped by geotextile to be used as a reverse filter layer before installation. And a 1.5mm single-sided self-adhesive waterproof coiled material full-vertical-shaft full-pavement is adopted between the primary support and the secondary lining. The annular construction joint and the settlement joint are provided with a middle-buried water stop. And a circumferential plastic blind ditch is arranged at each wall seat along the longitudinal direction of the vertical shaft, and four symmetrically arranged vertical phi 50 soft permeable pipes are used for discharging running water in the pipe into the lower part of the shaft and finally into a central drainage ditch of the main hole of the tunnel.

Claims (1)

1. The construction method of the tunnel vertical shaft is characterized by comprising the following steps: after the center of the shaft is calibrated, a shaft opening field is excavated at the periphery of the vertical shaft for meeting the construction requirement of the shaft;
the well mouth is 1.0m higher than the ground surface, a well ring and a locking ring of a C30 reinforced concrete structure are arranged in the vertical shaft within the range of 5m from the well mouth, and then C15 pieces of stone concrete are backfilled around the well mouth;
after a well head field is leveled, mechanical equipment is used for excavating a surface soil section of a well head of the vertical shaft, the excavating depth is 4m, the excavation is carried out in two layers, the excavating depth of each layer is 2m, and the excavating construction of the second layer is carried out after the first layer is excavated downwards by 2 m;
excavating a vertical shaft wellhead section to form and cleaning the bottom, and then constructing a locking ring; erecting reinforcing steel bars of the locking ring, erecting inner and outer templates of the locking ring after the reinforcing steel bars are erected, pouring concrete of the locking ring after the templates are erected, curing the concrete in time after the pouring is finished, removing the templates of the locking ring when the concrete is cured for 7 days and the strength reaches over 75% of the designed strength, backfilling the well ring wall to the height of a well mouth in a layered mode by adopting C15 pieces of stone concrete, wherein the backfilling height is 4m, the backfilling height of each layer is 1m, and the backfilling is finished in four times; after backfilling is finished, continuously maintaining the backfilled stone concrete and the inner walls of the well ring and the locking ring for 28 days, and performing next construction after the concrete reaches 100% of the designed strength;
when filling rubble concrete around the wellhead, simultaneously pouring foundations of four derrick column feet and two inclined strut column feet, wherein the column foot foundations are of a C30 reinforced concrete structure; simultaneously maintaining the column base foundation, the vertical shaft locking ring and the backfill stone concrete;
before the construction of a well mouth strengthening section, the installation work of lifting a derrick by a shaft is completed, a head sheave platform of the derrick is provided with a head sheave with the diameter of phi 1m, and a slag unloading platform is arranged above the well mouth;
the excavation of the soil and stones at the reinforcement section of the well mouth adopts the single-process circulation operation of mechanical excavation, manual trimming of excavation contour lines and lining; during excavation, directly grabbing surface soil and stones by using a grabbing head of a central rotary rock grab machine, loading the surface soil and stones into a lifting bucket, lifting the lifting bucket to a wellhead slag unloading platform by using a lifter, unloading the soil and stones to the surface of the wellhead, controlling the excavation depth of each layer of soil and stones to be 1m, manually finishing an excavation contour line after each layer of soil and stones is excavated, and performing primary support operation after finishing the excavation;
when a wellhead strengthening section is constructed for primary support, C25 concrete is sprayed firstly, concrete with the thickness of 4cm is sprayed firstly, then holes are drilled according to the positions of anchor rods on a well wall, the hole depth is 3m from the original rock of the well wall, after the holes are drilled, a radial hollow grouting anchor rod with the diameter of 25mm is constructed, then a reinforcing mesh is hung, the lap joint of a mesh piece is fixed by the anchor rods, a steel frame is erected near the primary spraying surface, when the steel frame is accurately in place and connecting steel bars are welded, secondary concrete spraying operation is immediately carried out, secondary concrete spraying is carried out in a layered mode, each layer is 5-6 cm, the thickness of the concrete reaches 22cm, and the surface of the concrete is smooth after the spraying is finished;
excavating the well body by adopting a drilling and blasting method, and carrying out primary support according to the surrounding rock condition of the shaft;
after the construction of the wellhead strengthening section is completed, a wellhead plate is timely installed on a wellhead, a fixed plate is arranged 5m below the wellhead plate, and a double-layer hanging scaffold is installed below the fixed plate;
from the reinforced section of the well head to the well bottom, a lining structure adopts hollow anchor rods, C25 sprayed concrete, a reinforcing mesh and C30 molded concrete, a wall seat lining structure adopts C30 reinforced concrete, a reinforced concrete reinforced section is arranged at the joint of a wall seat and a lining, and the wall thickness of the reinforced concrete reinforced section is 40 cm; c30 the molded concrete is secondary lining, the rest supporting materials are primary supporting construction, and after the shaft is tunneled from top to bottom and the primary supporting is completed, the construction operation of the secondary lining and the wall seat is carried out from bottom to top;
cleaning the pumice and the dangerous stones of the surrounding rocks around the working face in the tunneling working face, drilling blast holes, charging, warning and blasting, ventilating in time after blasting, cleaning the pumice and the dangerous stones on the hanging scaffold and the well wall after the air quality of the working face is qualified, and then grabbing and lifting the rocks; finally, carrying out primary support on the shaft, spraying concrete with the thickness of 4cm when spraying C25 concrete, then drilling holes by a rock chiseling worker according to the positions of the anchor rods on the well wall, wherein the hole depth extends 3m outwards from the original rock of the well wall, constructing the anchor rods after drilling, then hanging a reinforcing mesh, fixing the lap joints of the mesh sheets by the anchor rods, erecting a grid steel frame close to the primary spraying surface, setting at least 8 wedge-shaped cushion blocks at gaps, tightly jacking surrounding rocks, immediately carrying out secondary concrete spraying operation after the steel frame is accurately in place and connecting steel bars are welded, and spraying the concrete layer by layer to reach the designed thickness when spraying the concrete for the second time, wherein each layer is 5-6 cm, the thickness of the net protective layer of the profile steel frame is not less than 2cm, and the surface of the concrete after spraying is finished is smooth;
controlling the blasting excavation circulating footage within 1.0m, drilling blast holes by a rock drill, wherein the hole depth is 1.5-2 m, the hole diameter is 38-42 mm, and the loading of each hole is 0.6-1 kg; during excavation, a smooth blasting technology is adopted to control the surrounding rock overbreak and underexcavation;
blowing the rock surface from top to bottom by high-pressure air, and embedding a mark nail for controlling the thickness of sprayed concrete;
the spraying operation is performed along the well wall from bottom to top in a piling mode, so that the phenomenon that the upper spraying rebound material covers the lower well wall loosely and is not compact, and the instability is caused due to insufficient strength; leveling the concave part, then spraying the convex part, and smoothly connecting the concave part and the convex part;
the spraying operation moves in a spiral circle along the horizontal direction, the spray head is kept vertical to the sprayed surface as much as possible, and the distance from the nozzle opening to the sprayed surface is 0.6-1.0 m;
carrying out anchor rod installation operation in time after the concrete is initially sprayed;
the hollow anchor rod is grouted by adopting a single-liquid grouting pump, the mixed slurry enters the cylinder body through a slurry suction pump and is sent to a grouting pipe to reach a slurry discharge hole at the hollow bottom end of the anchor rod, and the slurry is pressed into a gap between a rock body and a rod body, so that surrounding rock is reinforced and the bearing capacity of a support system is improved;
the method comprises the following steps that a grid steel frame and a section steel frame are erected in time after a vertical shaft is excavated, 4cm of concrete is sprayed, radial anchor rods are constructed, a reinforcing mesh is hung, the steel frame is close to a primary spraying surface as much as possible, at least 8 wedge-shaped cushion blocks are arranged at gaps, surrounding rocks are tightly propped, and when the steel frame is accurately in place and connecting steel bars are welded, the concrete is sprayed immediately;
after the shaft is tunneled from top to bottom and the primary support is completely finished, secondary lining and wall seat construction are carried out from bottom to top; before the construction of secondary lining and wall seat, the installation of drainage system, the laying of waterproof coiled material, the installation of reinforcing steel bar and the installation of template are carried out, and then the concrete pouring process is carried out; constructing the lining from bottom to top by adopting a self-elevating hydraulic slip form process;
during construction, a self-elevating slip form is arranged at the bottom of a well and slides from bottom to top, and meanwhile, concrete is poured by the slip form while steel bars are bound; the sliding lifting of the sliding mould requires symmetrical and uniform blanking, normal construction is carried out layer by layer, each 30cm is a layer, an insertion type vibrator is adopted for vibrating, the vibrating direction is often changed, direct vibrating of a sliding rod and a template is avoided, the insertion depth of the vibrator is not more than 50cm in lower-layer concrete, and vibrating is stopped when the template slides; controlling the normal sliding speed to be 30cm and the daily sliding height to be about 3.6m at an interval of 2 hours every time;
when the mold-built lining construction is carried out to the position 1.5m below the wall seat, firstly, the wall seat is excavated and concrete is sprayed, the waterproof coiled material is paved and then steel bars are bound, then the concrete is poured by slip casting until the position 1.5m above the wall seat and the total height of the wall seat and the reinforcing section is 4 m;
when the sliding mould slides to a specified position, the sliding mould is removed at a wellhead by using a shaft lifting system after sliding to the empty;
after the shaft excavation is finished, arranging a vertical drainage pipe at the water dripping and leaking position on the surface of the surrounding rock of the shaft for centralized drainage and then performing concrete spraying construction; after the concrete is sprayed, vertically laying 4 soft permeable pipes on the surface of the sprayed concrete, uniformly arranging the 4 soft permeable pipes along the surface of the sprayed concrete, fixing the soft permeable pipes by using fixing nails, and wrapping the whole surface of the soft permeable pipes by adopting geotextile to serve as a reverse filter layer before the installation of the soft permeable pipes so as to prevent silt in the fissure water from blocking the permeable pipes; all the geotextile with the thickness of 400 g/square meter and the single-sided self-adhesive waterproof coiled material with the thickness of 1.5mm are paved on the surface of the sprayed concrete, a circumferential plastic blind ditch is arranged at the back of the waterproof coiled material according to the design requirement, seepage water flows into a phi 50 mm soft water permeable pipe connected with the circumferential plastic blind ditch through the circumferential plastic blind ditch, and the water is guided and drained to a central drainage ditch of a communication channel at the bottom of a well; a phi 50 mm annular plastic blind ditch is arranged at the top edge of the wall seat and is connected with the soft permeable pipe through a four-way pipe; applying the waterproof coiled material and the annular plastic blind ditch from bottom to top, and adopting geotextile full-surface wrapping as a reverse filter layer before the annular plastic blind ditch is installed; fully paving the primary support and the secondary lining by adopting a 1.5mm single-sided self-adhesive waterproof coiled material full-vertical shaft; a middle-buried water stop is arranged at the annular construction joint and the settlement joint; and a circumferential plastic blind ditch is arranged at each wall seat along the longitudinal direction of the vertical shaft, and four symmetrically arranged vertical phi 50 soft permeable pipes are used for discharging running water in the pipe into the lower part of the shaft and finally into a central drainage ditch of the main hole of the tunnel.
CN201911161105.4A 2019-11-24 2019-11-24 Tunnel shaft construction method Active CN110984999B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201911161105.4A CN110984999B (en) 2019-11-24 2019-11-24 Tunnel shaft construction method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201911161105.4A CN110984999B (en) 2019-11-24 2019-11-24 Tunnel shaft construction method

Publications (2)

Publication Number Publication Date
CN110984999A CN110984999A (en) 2020-04-10
CN110984999B true CN110984999B (en) 2021-09-21

Family

ID=70086115

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201911161105.4A Active CN110984999B (en) 2019-11-24 2019-11-24 Tunnel shaft construction method

Country Status (1)

Country Link
CN (1) CN110984999B (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111411967A (en) * 2020-04-01 2020-07-14 中铁二院工程集团有限责任公司 Construction method for tunnel vault vertical section discharge flue
CN111852482A (en) * 2020-07-31 2020-10-30 湖南科技大学 Construction method of ore crusher foundation of slip-breaking system engineering below 40m

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102155233A (en) * 2011-04-21 2011-08-17 上海市城市建设设计研究院 Tunnel excavation construction method
CN103114857A (en) * 2013-02-26 2013-05-22 中铁十九局集团第二工程有限公司 Shield tunnel construction method
CN105201513A (en) * 2015-09-11 2015-12-30 重庆工程职业技术学院 Shaft construction method for rail transit
RU2631061C1 (en) * 2016-06-24 2017-09-18 Общество с ограниченной ответственностью "Скуратовский опытно-экспериментальный завод" Method for construction of prefabricated-solid support of shaft of mining enterprise and device for its implementation
CN107419791A (en) * 2017-09-10 2017-12-01 沈阳建筑大学 Sewage conduct with processing toxic gas vertical shaft

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102155233A (en) * 2011-04-21 2011-08-17 上海市城市建设设计研究院 Tunnel excavation construction method
CN103114857A (en) * 2013-02-26 2013-05-22 中铁十九局集团第二工程有限公司 Shield tunnel construction method
CN105201513A (en) * 2015-09-11 2015-12-30 重庆工程职业技术学院 Shaft construction method for rail transit
RU2631061C1 (en) * 2016-06-24 2017-09-18 Общество с ограниченной ответственностью "Скуратовский опытно-экспериментальный завод" Method for construction of prefabricated-solid support of shaft of mining enterprise and device for its implementation
CN107419791A (en) * 2017-09-10 2017-12-01 沈阳建筑大学 Sewage conduct with processing toxic gas vertical shaft

Also Published As

Publication number Publication date
CN110984999A (en) 2020-04-10

Similar Documents

Publication Publication Date Title
CN110984999B (en) Tunnel shaft construction method
CN101864960A (en) Carst region double-arch road tunnel construction method
CN106320120A (en) Construction process for pile slab type non-soil roadbed highway
CN108914931B (en) Assembled vertical shield annular foundation pile and construction method
CN110656959B (en) Large-section loess tunnel primary support limit-invasion arch-changing construction method
CN109024657B (en) Construction method of super high-rise core tube deep pit edge tower crane foundation under complex conditions
CN108035379B (en) Comprehensive pipe gallery and construction method thereof
CN105804089A (en) Locally-deepened supporting and protecting system used after original deep foundation pit is constructed and construction method of system
CN110792440B (en) Construction method of water-rich loess tunnel penetrating through loess towards valley
CN110847929B (en) Tunnel portal section pre-reinforcing and excavating construction method based on partition blasting
CN111119128B (en) Danger-removing, reinforcing and seepage-proofing method for natural rock-fill dam of barrier lake
CN110821500B (en) Large-section tunnel excavation and support construction method for penetrating through earth-rock boundary stratum
CN110863496B (en) Method for replacing, supporting, excavating and constructing arch center foundation by concrete supporting in stone-filled island building area
CN211258631U (en) Loess tunnel basement reinforcement construction structure based on high pressure jet grouting pile
CN111576431A (en) Excavation method for foundation pit of four-layer subway station
CN209687506U (en) Wear river shallow buried covered excavation electric power tunnel constructing structure
CN110671132A (en) Deformation control construction structure and method for deep-buried loess tunnel based on arch sheathing
CN110671131A (en) Loess tunnel substrate reinforcing structure and method based on high-pressure jet grouting pile
CN108385612B (en) Construction method of concrete protective panel with good stability
CN110761808A (en) Large-section loess tunnel supporting system and supporting construction method
CN110777775A (en) Foundation pit structure and construction method thereof
CN111058456A (en) Cast-in-place pile construction method in foundation pit supporting process
CN104963348B (en) A kind of soft clay area tower crane construction supporting structure and its construction method
CN109706952A (en) Large-scale well-sinking construction method
CN109339100A (en) A kind of open trench tunnel falsework system and construction

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant