阅读说明：本技术 低净空狭小空间下硬岩地层桩基施工方法及其施工设备 (Construction method and construction equipment for hard rock stratum pile foundation in low-clearance narrow space ) 是由 温法庆 张爱军 刘晏斌 崔连友 张守同 李克金 王忠仁 闫利亚 于 2020-05-11 设计创作，主要内容包括：本发明公开了一种低净空狭小空间下硬岩地层桩基施工方法,包括以下步骤：S1、在车站外侧依次开挖竖井和横通道；S2、导洞开挖及初期支护；S3、下部中间导洞内侧下部分施工底纵梁；S4、钻成孔；S5、施工上部边导洞围护桩；S6、施工上部中间导洞和下部中间导洞之间的钢管柱；S7、钻孔设备撤场。本发明采用上述低净空狭小空间下硬岩地层桩基施工方法及其施工设备,通过采用空压机和气动潜孔锤钻机组成的钻孔设备,可对超低净空狭小空间下的硬岩地层灌注进行钻孔,从而解决了人工挖孔桩工效低、风险大的难题,为硬岩地层中地铁暗挖车站围护结构、钢管柱的施工提供了有效的解决方案；同时配合水雾除尘器,除尘解决了岩层破碎带来的扬尘污染。(The invention discloses a hard rock stratum pile foundation construction method in a low-clearance narrow space, which comprises the following steps of: s1, excavating vertical shafts and transverse channels on the outer side of the station in sequence; s2, excavating a pilot tunnel and performing primary support; s3, constructing a bottom longitudinal beam at the lower part of the inner side of the lower middle pilot tunnel; s4, drilling a hole; s5, constructing an upper side pilot tunnel fender post; s6, constructing the steel pipe column between the upper middle pilot tunnel and the lower middle pilot tunnel; and S7, removing the drilling equipment. By adopting the construction method and the construction equipment for the pile foundation of the hard rock stratum in the low-clearance narrow space, the hard rock stratum in the ultra-low-clearance narrow space can be poured and drilled by adopting the drilling equipment consisting of the air compressor and the pneumatic down-the-hole hammer drill, so that the problems of low work efficiency and high risk of the manual hole digging pile are solved, and an effective solution is provided for the construction of a subway underground excavation station enclosure structure and a steel pipe column in the hard rock stratum; meanwhile, by matching with a water mist dust remover, dust removal is realized, and dust pollution caused by rock stratum crushing is avoided.)

1. A hard rock stratum pile foundation construction method in a low-clearance narrow space is characterized by comprising the following steps: the method comprises the following steps:

s1, excavating vertical shafts and transverse channels on the outer side of the station in sequence;

s2, pilot tunnel excavation and preliminary bracing

Before pilot tunnel excavation, pre-grouting in advance to reinforce a stratum, sequentially excavating an upper side pilot tunnel, an upper middle pilot tunnel and a lower middle pilot tunnel, and synchronously carrying out primary support on the tunnel wall of the excavated pilot tunnel in the excavation process;

s3, constructing a bottom longitudinal beam at the lower part of the inner side of the lower middle pilot tunnel;

s4 drilling a hole

S41, hoisting and lowering the parts of the drilling equipment into the well in sequence;

s42, assembling

An air compressor unit of the drilling equipment is communicated with an air inlet of a power head of a pneumatic down-the-hole hammer drill through an exhaust pipe, a flow divider and a confluent air pipe in sequence, and an outlet of the power head of the pneumatic down-the-hole hammer drill is communicated with a water mist dust remover through a slag discharge pipe;

s43, adjusting the power head position of the pneumatic down-the-hole hammer drill according to the arrangement point position of the fender post of the underground excavation station;

s44, drilling

Sequentially starting an air compressor and a water mist dust remover, drilling by adopting a hole isolation drilling method, and stopping drilling after the drilling reaches a certain depth;

s5 construction upper side pilot tunnel fender post

S51, manufacturing and hanging the fender pile reinforcement cage in sections;

s52, connecting the segmented reinforcement cages by using steel connectors to form an integral reinforcement cage;

s53, pouring concrete to finish the construction of the fender post;

s6, constructing the steel pipe column between the upper middle pilot tunnel and the lower middle pilot tunnel;

s61, sequentially starting the air compressor and the water mist dust remover, and drilling until the hole is drilled to the top of the middle pilot tunnel at the lower part, and stopping drilling;

s62, shearing off primary reinforcing steel bars at the top of the middle pilot tunnel at the lower part of the pore-forming range, so that no reinforcing steel bar head is exposed at the pore wall;

s63, hoisting the steel pipe column in sections;

s64, connecting the sectional steel pipe columns by adopting high-strength bolts;

s65, detecting the verticality and connection reliability of the steel pipe column and the bottom longitudinal beam in the middle pilot tunnel at the lower part;

and S7, removing the drilling equipment.

2. The method for constructing the pile foundation of the hard rock stratum in the low-clearance narrow space of the claim 1, which is characterized in that: and reserving reinforcing steel bar heads for connecting subsequent reinforcing steel bars in the primary support grids of the upper side pilot hole and the upper middle pilot hole in the step S2.

3. The method for constructing the pile foundation of the hard rock stratum in the low-clearance narrow space of the claim 1, which is characterized in that: the lower middle pilot tunnel excavated in the step S2 is located right below the upper middle pilot tunnel.

4. The method for constructing the pile foundation of the hard rock stratum in the low-clearance narrow space of the claim 1, which is characterized in that: the hole-separating drilling method in step S44 is implemented by drilling one hole every four holes.

5. The method for constructing the pile foundation of the hard rock stratum in the low-clearance narrow space of the claim 1, which is characterized in that: in step S53, the concrete is conveyed by a ground pump.

6. The method for constructing the pile foundation of the hard rock stratum in the low-clearance narrow space of the claim 1, which is characterized in that: the step S65 is followed by: and filling fine sand into the gap between the steel pipe column and the pore wall of the pore.

7. A construction equipment for a hard rock stratum pile foundation construction method in a low-clearance narrow space based on any one of the claims 1 to 6, characterized in that: including drilling equipment, drilling equipment includes air compressor unit and pneumatic down-the-hole hammer rig, air compressor unit in proper order through blast pipe, shunt, join the trachea with the unit head air inlet intercommunication of pneumatic down-the-hole hammer rig, the export of pneumatic down-the-hole hammer rig unit head is through slagging tap pipe intercommunication water smoke dust remover.

8. The construction equipment of the hard rock stratum pile foundation construction method based on the low-clearance narrow space of claim 7, characterized in that: the pneumatic down-the-hole hammer drilling machine comprises a walking unit, a main control chamber arranged on the walking unit, a pushing unit connected with the output end of the main control chamber, an air box connected with the pushing unit and a power head connected with the air box.

9. The construction equipment of the hard rock stratum pile foundation construction method based on the low-clearance narrow space of claim 7, characterized in that: the air compressor unit comprises four air compressors which are communicated with the shunt through the exhaust pipes.

10. The construction equipment of the hard rock stratum pile foundation construction method based on the low-clearance narrow space of claim 8, characterized in that: the walking unit is a crawler-type walking mechanism.

Technical Field

The invention relates to a subway construction technology, in particular to a hard rock stratum pile foundation construction method and construction equipment thereof in a low-clearance narrow space.

Background

With the continuous development of urban rail transit, underground stations of rail transit construction in urban downtown areas or main roads are influenced by a plurality of peripheral engineering environments and traffic dispersion, when the contradiction between the open excavation construction of subway stations and the ground traffic dispersion is difficult to solve, cover excavation (half cover excavation) is usually adopted for construction, namely, the ground traffic is required to be closed in a short time to complete the construction of a station roof (partial roof), then the ground traffic is recovered, a plurality of pipelines are difficult to move and change at the position of an urban main road or a ground traffic junction, the local closure of a traffic road can also bring great adverse effect on the ground traffic, and even road traffic paralysis in a certain time period is caused.

In order to solve the adverse effect of the construction on road traffic, the underground excavation method is mostly adopted for construction, namely, a vertical shaft is constructed at the edge of a road, a transverse passage is constructed in the vertical shaft, and the sectional excavation is carried out on a station in a subarea manner, so that the series adverse effect on ground traffic can be solved. In the underground excavation construction process of the station, in order to ensure the safety of large-section underground excavation construction and the durability of a main structure of the station and the safety of subway operation, a fender post structure needs to be constructed for the subway station, a manual hole digging pile or a reverse circulation drilling machine construction method is usually adopted in a soft soil stratum, fender posts are constructed around the underground excavation station, and a separate straddle column structure of the station is matched to meet the stress requirements of excavation construction and the main structure of the station.

However, manual hole digging is difficult to implement in hard rock strata, particularly in strata with the pressure of more than 30-40 MPa and even more than 100MPa, and a reverse circulation drilling machine cannot be constructed.

Based on the engineering background condition, the invention provides a hard rock stratum pile foundation construction method and construction equipment thereof in a low-clearance narrow space, aiming at improving the construction efficiency of underground excavation station fender posts or station spanning upright posts and ensuring the safety of pile foundation construction.

Disclosure of Invention

The invention aims to provide a hard rock stratum pile foundation construction method and construction equipment thereof in a low-clearance narrow space, wherein the hard rock stratum in an ultra-low-clearance narrow space can be poured and drilled by adopting drilling equipment consisting of an air compressor and a pneumatic down-the-hole hammer drill, so that the problems of low work efficiency and high risk of a manual hole digging pile are solved, and an effective solution is provided for the construction of a subway underground excavation station enclosure structure and a steel pipe column in a hard rock stratum; meanwhile, by matching with a water mist dust remover, dust removal is realized, and dust pollution caused by rock stratum crushing is avoided.

In order to achieve the aim, the invention provides a hard rock stratum pile foundation construction method in a low-clearance narrow space, which comprises the following steps:

s1, excavating vertical shafts and transverse channels on the outer side of the station in sequence;

s2, pilot tunnel excavation and preliminary bracing

Before pilot tunnel excavation, pre-grouting in advance to reinforce a stratum, sequentially excavating an upper side pilot tunnel, an upper middle pilot tunnel and a lower middle pilot tunnel, and synchronously carrying out primary support on the tunnel wall of the excavated pilot tunnel in the excavation process;

s3, constructing a bottom longitudinal beam at the lower part of the inner side of the lower middle pilot tunnel;

s4 drilling a hole

S41, hoisting and lowering the parts of the drilling equipment into the well in sequence;

s42, assembling

An air compressor unit of the drilling equipment is communicated with an air inlet of a power head of a pneumatic down-the-hole hammer drill through an exhaust pipe, a flow divider and a confluent air pipe in sequence, and an outlet of the power head of the pneumatic down-the-hole hammer drill is communicated with a water mist dust remover through a slag discharge pipe;

s43, adjusting the power head position of the pneumatic down-the-hole hammer drill according to the arrangement point position of the fender post of the underground excavation station;

s44, drilling

Sequentially starting an air compressor and a water mist dust remover, drilling by adopting a hole isolation drilling method, and stopping drilling after the drilling reaches a certain depth;

s5 construction upper side pilot tunnel fender post

S51, manufacturing and hanging the fender pile reinforcement cage in sections;

s52, connecting the segmented reinforcement cages by using steel connectors to form an integral reinforcement cage;

s53, pouring concrete to finish the construction of the fender post;

s6, constructing the steel pipe column between the upper middle pilot tunnel and the lower middle pilot tunnel;

s61, sequentially starting the air compressor and the water mist dust remover, and drilling until the hole is drilled to the top of the middle pilot tunnel at the lower part, and stopping drilling;

s62, shearing off primary reinforcing steel bars at the top of the middle pilot tunnel at the lower part of the pore-forming range, so that no reinforcing steel bar head is exposed at the pore wall;

s63, hoisting the steel pipe column in sections;

s64, connecting the sectional steel pipe columns by adopting high-strength bolts;

s65, detecting the verticality and connection reliability of the steel pipe column and the bottom longitudinal beam in the middle pilot tunnel at the lower part;

and S7, removing the drilling equipment.

Preferably, in step S2, reinforcing heads for connecting subsequent reinforcing bars are reserved on the primary grids of the upper side pilot hole and the upper middle pilot hole.

Preferably, the lower middle pilot tunnel excavated in the step S2 is located right below the upper middle pilot tunnel.

Preferably, the alternate hole drilling method in step S44 is implemented by drilling every fourth hole.

Preferably, the concrete is delivered by a ground pump in step S53.

Preferably, after step S65, the method further includes: and filling fine sand into the gap between the steel pipe column and the pore wall of the pore.

The utility model provides a construction equipment based on hard rock stratum pile foundation construction method under narrow and small space of low headroom, includes drilling equipment, drilling equipment includes air compressor unit and pneumatic down-the-hole hammer rig, the air compressor unit in proper order through blast pipe, shunt, join the trachea with the unit head air inlet intercommunication of pneumatic down-the-hole hammer rig, the export of pneumatic down-the-hole hammer rig unit head is through slagging tap pipe intercommunication water smoke dust remover.

Preferably, the pneumatic down-the-hole hammer drill comprises a walking unit, a main control chamber arranged on the walking unit, a pushing unit connected with the output end of the main control chamber, an air box connected with the pushing unit and a power head connected with the air box.

Preferably, the air compressor unit comprises four air compressors which are communicated with the flow divider through the exhaust pipes.

Preferably, the running unit is a crawler-type running mechanism.

Therefore, the construction method and the construction equipment for the pile foundation of the hard rock stratum in the low-clearance narrow space are adopted, and the drilling equipment consisting of the air compressor and the pneumatic down-the-hole hammer drill is adopted, so that the hard rock stratum in the ultra-low-clearance narrow space can be poured for drilling, the problems of low work efficiency and high risk of the manual hole digging pile are solved, and an effective solution is provided for the construction of the enclosure structure of the subway underground excavation station and the steel pipe column in the hard rock stratum; meanwhile, by matching with a water mist dust remover, dust removal is realized, and dust pollution caused by rock stratum crushing is avoided.

The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.

Drawings

Fig. 1 is a construction diagram of a hard rock stratum pile foundation construction method and construction equipment thereof in a low-clearance narrow space according to an embodiment of the invention;

fig. 2 is a schematic structural diagram of a drilling device of a hard rock stratum pile foundation construction method and a construction device thereof in a low-clearance narrow space according to an embodiment of the invention;

fig. 3 is a schematic structural diagram of a drilling device of a hard rock stratum pile foundation construction method and a construction device thereof in a low-clearance narrow space according to an embodiment of the invention;

fig. 4 is a schematic cross-sectional structure diagram of a pneumatic down-the-hole hammer drill of a hard rock stratum pile foundation construction method and a construction device thereof in a low-clearance narrow space in an embodiment of the invention.

Wherein: 1. guiding holes on the upper side; 2. a middle pilot tunnel at the upper part; 3. a lower middle pilot tunnel; 4. a fender pile; 5. a bottom stringer; 6. drilling equipment; 60. a pneumatic down-the-hole hammer drill; 600. a traveling unit; 601. a master control room; 602. a pushing unit; 603. a gas box; 604. a power head; 61. a slag pipe; 62. an air compressor; 63. a flow divider; 64. an exhaust pipe; 65. a water mist dust remover; 66. converging an air pipe; 7. fine sand; 8. steel pipe columns; 9. and (6) forming holes.

Detailed Description

The present invention will be further described with reference to the accompanying drawings, and it should be noted that the present embodiment is based on the technical solution, and the detailed implementation and the specific operation process are provided, but the protection scope of the present invention is not limited to the present embodiment.

Fig. 1 is a construction diagram of a hard rock stratum pile foundation construction method and construction equipment thereof in a low-clearance narrow space according to an embodiment of the invention; fig. 2 is a schematic structural diagram of a drilling device of a hard rock stratum pile foundation construction method and a construction device thereof in a low-clearance narrow space according to an embodiment of the invention; fig. 3 is a schematic structural diagram of a drilling device of a hard rock stratum pile foundation construction method and a construction device thereof in a low-clearance narrow space according to an embodiment of the invention; fig. 4 is a schematic cross-sectional structure diagram of a pneumatic down-the-hole hammer drill of a hard rock stratum pile foundation construction method and a construction device thereof in a low-clearance narrow space, according to the embodiment of the invention, as shown in the figure, the method comprises the following steps:

s1, excavating vertical shafts and transverse channels on the outer side of the station in sequence;

s2, pilot tunnel excavation and preliminary bracing

Before pilot tunnel excavation, pre-grouting in advance to reinforce a stratum, sequentially excavating an upper side pilot tunnel 1, an upper middle pilot tunnel 2 and a lower middle pilot tunnel 3, and synchronously carrying out primary support on the excavated pilot tunnel wall in the excavation process;

preferably, in step S2, reinforcing heads for connecting subsequent reinforcing steel bars are reserved on the primary supporting grids of the upper side pilot tunnel 1 and the upper middle pilot tunnel 2.

Preferably, the lower middle pilot tunnel 3 excavated in step S2 is located right below the upper middle pilot tunnel 2.

S3, constructing a bottom longitudinal beam 5 at the lower part of the inner side of the lower middle pilot tunnel 3;

s4 drilling a hole 9

S41, hoisting and lowering the parts of the drilling equipment 6 into the well in sequence;

s42, assembling

The air compressor 62 group of the drilling equipment 6 is communicated with the air inlet of the power head 604 of the pneumatic down-the-hole hammer drill 60 through an exhaust pipe 64, a flow divider 63 and a confluent air pipe 66 in sequence, and the outlet of the power head of the pneumatic down-the-hole hammer drill 60 is communicated with a water mist dust remover 65 through a slag discharging pipe 61;

s43, adjusting the position of a power head 604 of the pneumatic down-the-hole hammer drill 60 according to the arrangement point position of the fender post 4 of the underground excavation station;

s44, drilling

Sequentially starting the air compressor 62 and the water mist dust remover 65, drilling by adopting a hole isolation drilling method, and stopping drilling after the drilling reaches a certain depth;

preferably, the alternate hole drilling method in step S44 is performed by drilling every fourth hole.

S5, constructing the upper side pilot tunnel 1 fender post 4

S51, manufacturing a 4 steel reinforcement cage for the hanging fender post in sections;

s52, connecting the segmented reinforcement cages by using steel connectors to form an integral reinforcement cage;

s53, pouring concrete to finish the construction of the fender post 4;

preferably, the concrete is delivered by a ground pump in step S53.

S6, constructing the steel pipe column 8 between the upper middle pilot tunnel 2 and the lower middle pilot tunnel 3;

s61, sequentially starting the air compressor 62 and the water mist dust collector 65, drilling, stopping drilling until the drilling reaches the top of the lower middle pilot tunnel 3, judging the drilling to the top when slag is obviously reduced in drilling, stopping the operation of operators at the moment, wherein in the process of 8-hole construction of the steel pipe column, people or equipment parking is forbidden near the corresponding position of the lower middle pilot tunnel 3;

s62, cutting off primary reinforcing steel bars at the top of the middle pilot tunnel 3 at the lower part of the range of the formed hole 9, so that no reinforcing steel bar head is exposed at the hole wall;

s63, hoisting the steel pipe column 8 in sections;

s64, connecting the sectional steel pipe columns 8 by adopting high-strength bolts;

s65, detecting the verticality and connection reliability of the steel pipe column 8 and the bottom longitudinal beam 5 in the lower middle pilot tunnel 3;

preferably, step S65 is followed by: and the fine sand 7 is filled in the gap between the steel pipe column 8 and the hole wall of the formed hole 9, so that the rigidity of the steel pipe column 8 is improved, and the protection of the steel pipe column 8 in the soil body excavation process is facilitated.

And S7, withdrawing the drilling equipment field 6.

A construction device based on a hard rock stratum pile foundation construction method in a low-clearance narrow space comprises a drilling device 6, wherein the drilling device 6 comprises an air compressor 62 group and a pneumatic down-the-hole hammer drill 60, the air compressor 62 group is communicated with an air inlet of a power head 604 of the pneumatic down-the-hole hammer drill 60 through an exhaust pipe 64, a flow divider 63 and a confluent air pipe 66 in sequence, and an outlet of the power head of the pneumatic down-the-hole hammer drill 60 is communicated with a water mist dust remover 65 through a slag pipe 61. More specifically, the pneumatic down-the-hole hammer drill 60 includes a traveling unit 600, a main control room 601 provided on the traveling unit 600, a pushing unit 602 connected to an output end of the main control room 601, an air box 603 connected to the pushing unit 602, and a power head 604 connected to the air box 603. Wherein the traveling unit 600 is a crawler type traveling mechanism. Preferably, the air compressor 62 group includes four air compressors 62 that all communicate with shunt 63 through blast pipe 64, and the theory of operation of pneumatic down-the-hole hammer rig 60 is the common general knowledge in the art, so do not need to be repeated here, and this application has satisfied the construction environment in low headroom narrow and small space through arranging it and optimizing.

The working process of the drilling equipment 6 is as follows: before drilling, the air compressor 62 and the water mist dust remover are sequentially started according to the operation rules, after the system equipment is checked to be abnormal, the power head 604 is started to drill, namely, high-pressure gas generated by the air compressor 62 is converged by the exhaust pipe 64 and the flow divider 63 and then enters an air inlet pipeline of the power head 604 through the converging air pipe 66, the power head 604 is pushed by the high-pressure air to impact and drill a broken rock stratum, pressure air carrying drilling slag discharged from the bottom of a hole is discharged into the water mist dust remover 65 through the slag discharging pipe 61, and the drilling slag is stacked and transported outside after being subjected to dust fall through water mist.

The exhaust pipe 64, the merged gas pipe 66, and the slag discharge pipe 61 are all high-pressure pipes.

The invention can also be used for the construction of the pile foundation of the hard rock stratum which has high requirements on dust raising and noise control and limited ground space.

Therefore, the construction method and the construction equipment for the pile foundation of the hard rock stratum in the low-clearance narrow space are adopted, and the drilling equipment consisting of the air compressor and the pneumatic down-the-hole hammer drill is adopted, so that the hard rock stratum in the ultra-low-clearance narrow space can be poured for drilling, the problems of low work efficiency and high risk of the manual hole digging pile are solved, and an effective solution is provided for the construction of the enclosure structure of the subway underground excavation station and the steel pipe column in the hard rock stratum; meanwhile, by matching with a water mist dust remover, dust removal is realized, and dust pollution caused by rock stratum crushing is avoided.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting the same, and although the present invention is described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that: modifications and equivalents may be made to the invention without departing from the spirit and scope of the invention.