阅读说明：本技术 一种盾构隧道土压力盒固定装置及安装方法 (Fixing device and mounting method for soil pressure box of shield tunnel ) 是由 胡亚东 马金根 肖华波 于 2019-12-19 设计创作，主要内容包括：本发明涉及隧道工程技术领域,具体涉及一种盾构隧道土压力盒固定装置；所采用的技术方案是：一种盾构隧道土压力盒固定装置,包括土压力盒固定装置本体、安装座,所述安装座用于安装土压力盒,所述安装座底端设有支撑杆,所述支撑杆外套有固定基座,所述固定基座在支撑杆长度方向的位置可调；所述安装座使用时安装在管片壁后注浆体内,以使土压力盒上端紧靠隧道围岩；所述固定基座使用时插设在盾构管片内,并与盾构管片固定连接。本发明在盾构管片和管片壁后注浆体筑设完成后,通过土压力盒固定装置,能够避免注浆对土压力盒造成损害、避免注浆影响土压力盒测量的准确性。(The invention relates to the technical field of tunnel engineering, in particular to a fixing device for a soil pressure box of a shield tunnel; the adopted technical scheme is as follows: a shield tunnel soil pressure cell fixing device comprises a soil pressure cell fixing device body and a mounting seat, wherein the mounting seat is used for mounting a soil pressure cell, a supporting rod is arranged at the bottom end of the mounting seat, a fixing base is sleeved outside the supporting rod, and the position of the fixing base in the length direction of the supporting rod is adjustable; when in use, the mounting seat is mounted in the duct piece wall back grouting body, so that the upper end of the soil pressure box is close to the tunnel surrounding rock; the fixed base is inserted in the shield pipe piece when in use and is fixedly connected with the shield pipe piece. According to the invention, after the shield segment and the segment wall post-grouting body are built, the soil pressure box fixing device can prevent the grouting from damaging the soil pressure box and prevent the grouting from influencing the accuracy of the soil pressure box measurement.)

1. The utility model provides a shield tunnel soil pressure cell fixing device, includes soil pressure cell fixing device body (1), mount pad (6) are used for installing soil pressure cell (21), its characterized in that: a supporting rod (13) is arranged at the bottom end of the mounting seat (6), a fixing base (14) is sleeved outside the supporting rod (13), and the position of the fixing base (14) in the length direction of the supporting rod (13) is adjustable;

when in use, the mounting seat (6) is mounted in the duct piece wall back grouting body so that the upper end of the soil pressure box (21) abuts against the tunnel surrounding rock;

the fixed base (14) is inserted into the shield segment (2) when in use and is fixedly connected with the shield segment (2).

2. The shield tunnel earth pressure cell fixing device of claim 1, characterized in that: the fixed base (14) penetrates through a grouting hole (18), and the grouting hole (18) is used for grouting a space between the fixed base (14) and the mounting seat (6).

3. The shield tunnel earth pressure cell fixing device of claim 2, characterized in that: the bottom end of the mounting seat (6) is further fixed with a grout stopping ring (12), and the grout stopping ring (12) is used for preventing grout from entering the mounting seat (6).

4. The shield tunnel earth pressure cell fixing device of claim 1, characterized in that: the supporting rod (13) is a screw rod, the fixing base (14) is provided with a through hole (20), and the supporting rod (13) penetrates through the through hole (20);

an inner nut (15) and an outer nut (19) are sleeved on the rod part of the supporting rod (13), and the inner nut (15) and the outer nut (19) are used for adjusting the position of the fixing base (14) in the length direction of the supporting rod (13).

5. The shield tunnel earth pressure cell fixing device of claim 4, characterized in that: the shield tunnel is characterized by further comprising a mounting sleeve (23), wherein the mounting sleeve (23) is inserted into the shield segment (2) when in use and is fixedly connected with the shield segment (2);

the mounting sleeve (23) is a threaded pipe, the outer side wall of the fixing base (14) is provided with an external thread matched with the mounting sleeve (23), and the mounting sleeve (23) is in threaded connection with the fixing base (14) when in use.

6. The shield tunnel earth pressure cell fixing device of claim 5, characterized in that: the bottom of the fixed base (14) is further fixed with a mounting nut (16), the mounting nut (16) and the through hole (20) are concentrically arranged, and the small diameter of the mounting nut (16) is larger than the outer diameter of the outer nut (19).

7. The shield tunnel earth pressure cell fixing device of claim 1, characterized in that: the mounting seat (6) is in a concave disc shape, a rubber ring (9) is fixed in the mounting seat (6), and the rubber ring (9) is used for fixing the soil pressure cell (21).

8. The shield tunnel earth pressure cell fixing device of claim 1, characterized in that: the supporting rod (13) is a hollow rod piece, a threading hole (7) is formed in the bottom of the mounting seat (6), and the threading hole (7) is communicated with a cavity of the supporting rod (13); the soil pressure cell is characterized in that a penetrating groove (8) is formed in the bottom of the mounting seat (6), the penetrating groove (8) is communicated with the penetrating hole (7), and the supporting rod (13) is provided with a cavity, the penetrating hole (7) and the penetrating groove (8) and is used for arranging a cable (22) of the soil pressure cell (21).

9. A method for installing a shield tunnel soil pressure cell, comprising the shield tunnel soil pressure cell fixing device of any one of claims 1 to 8, the method comprising the steps of:

assembling the soil pressure box fixing device body, and fixing the soil pressure box on the soil pressure box fixing device body;

fixedly connecting the mounting sleeve with the steel bars in the shield segment, plugging two ends of the mounting sleeve, and then pouring the shield segment in the shield segment template;

mounting a shield segment, and grouting a gap between the shield segment and surrounding rocks of the tunnel to form a segment wall post-grouting body;

taking out the end plug in the installation sleeve, drilling an installation channel in the duct piece wall back grouting body through the installation sleeve, and drilling the installation channel to tunnel surrounding rocks;

installing the soil pressure box fixing device body in the installation channel and fixedly connecting the soil pressure box fixing device body with the installation sleeve;

and grouting the installation sleeve and the installation channel to finish the fixed installation of the soil pressure cell.

10. The method for installing the soil pressure cell of the shield tunnel according to claim 9, wherein when the soil pressure cell fixing device is installed, a cable of the soil pressure cell is connected with a reading instrument, and whether the soil pressure cell is completely contacted with the surrounding rock of the tunnel is judged by observing data change of the reading instrument.

Technical Field

The invention relates to the technical field of tunnel engineering, in particular to a fixing device and an installation method for a soil pressure box of a shield tunnel.

Background

The shield method tunnel construction has the advantages of high tunneling speed, good construction quality, small disturbance to surrounding rocks, no influence on ground traffic and facilities and the like, and is widely applied to tunnel engineering construction in the industries of water conservancy and hydropower, rail traffic, railways, highways and the like in recent years. Due to the complex geological conditions of tunnel engineering, the tunnel engineering is greatly influenced by fault fracture zones, underground water, surrounding rock categories and the like, and the requirement on surrounding rock deformation control is extremely high. In construction, instruments such as a soil pressure cell, a steel bar meter and a strain gauge are generally adopted to measure parameters such as stress strain of tunnel surrounding rock so as to evaluate the deformation tendency, degree and stability of the tunnel surrounding rock.

At present, the shield tunnel soil pressure cell fixing device is implemented as follows: the top of the soil pressure box fixing device is flushed with the outer side wall of a prefabricated shield segment, then the soil pressure box fixing device is connected with the shield segment in a steel bar welding mode, the top of the soil pressure box fixing device is temporarily plugged, and finally the shield segment is poured in a shield segment template. The following problems mainly exist in the fixing and mounting mode: firstly, the soil pressure box arranged in the shield segment is easy to fall off and even damage; secondly, the soil pressure cell is not in direct contact with the tunnel surrounding rock, but is in indirect contact with the tunnel surrounding rock through the duct piece wall back grouting body, so that the measurement data error is large; when the shield segment is incompletely filled by grouting behind the wall, the grouting body is unevenly contacted with the soil pressure cell or the pea gravel is in point-surface contact with the measuring surface of the soil pressure cell, so that the error of the measured data is further increased; thirdly, the grouting pressure behind the shield segment wall is higher, and the soil pressure box is easily damaged in the grouting process; fourthly, the soil pressure cell fixing device, the shield segment and the hardened grouting body are easily integrated after the grouting slurry is hardened, so that the soil pressure cell does not have the function of measuring the soil pressure any more.

Disclosure of Invention

Aiming at the technical problems that the existing shield tunnel soil pressure cell is easy to fall off and damage, has large measurement error and is easy to lose efficacy; the invention provides a fixing device for a soil pressure box of a shield tunnel, which ensures that the soil pressure box is firmly and reliably installed, can prevent the shield duct piece wall back grouting from influencing the measurement result of the pressure box or damaging the pressure box, and ensures that the measured data of the pressure box is reliable and accurate.

The invention is realized by the following technical scheme:

a shield tunnel soil pressure cell fixing device comprises a soil pressure cell fixing device body and a mounting seat, wherein the mounting seat is used for mounting a soil pressure cell, a supporting rod is arranged at the bottom end of the mounting seat, a fixing base is sleeved outside the supporting rod, and the position of the fixing base in the length direction of the supporting rod is adjustable; when in use, the mounting seat is mounted in the duct piece wall back grouting body, so that the upper end of the soil pressure box is close to the tunnel surrounding rock; the fixed base is inserted in the shield pipe piece when in use and is fixedly connected with the shield pipe piece.

After the construction of the shield segment and the segment wall post-grouting body is finished, the soil pressure cell is fixed through the soil pressure cell fixing device body; the fixing base of the fixing device is fixedly connected with the shield segment, and the position of the fixing base in the length direction of the lower end supporting rod of the mounting seat is adjustable, so that the soil pressure box is in direct contact with the tunnel surrounding rock according to the set initial pressure. The damage of the grouting to the soil pressure cell can be avoided, and the influence of the grouting on the accuracy of the soil pressure cell measurement is avoided. Therefore, the error of the measuring result of the soil pressure cell is small, and the monitoring result can accurately reflect the soil pressure of the surrounding rock of the tunnel.

Furthermore, the fixed base penetrates through and is provided with a grouting hole, and the grouting hole is used for grouting a space between the fixed base and the mounting seat. The concrete is poured through the grouting holes, gaps among the body of the complete filling soil pressure cell fixing device, the shield segment and the segment back grouting body are formed, the mounting hole grouting body tightly bonded with the shield segment and the segment back grouting body is formed, and the completeness of the shield segment and the segment wall back grouting body is ensured.

Furthermore, the bottom end of the mounting seat is also fixedly provided with a grout stopping ring, and the grout stopping ring is used for preventing grout from entering the mounting seat so as to protect the soil pressure cell.

Preferably, the support rod is a screw rod, the fixed base is provided with a through hole, and the support rod is arranged in the through hole in a penetrating mode. The position of the fixed base is adjusted through the screw rod, so that the position of the fixed base is simple and convenient to adjust, and the adjusting linearity is good.

As a specific embodiment of the fixed base position adjustment: the supporting rod part is sleeved with an inner nut and an outer nut, and the inner nut and the outer nut are used for adjusting the position of the fixing base in the length direction of the supporting rod. The shield pipe is characterized by further comprising a mounting sleeve, wherein the mounting sleeve is inserted into the shield pipe piece when in use and is fixedly connected with the shield pipe piece; the mounting sleeve is a threaded pipe, the outer side wall of the fixing base is provided with an external thread matched with the mounting sleeve, and the mounting sleeve is in threaded connection with the fixing base when in use.

Preferably, the bottom of the fixed base is further fixed with a mounting nut, the mounting nut and the through hole are concentrically arranged, and the small diameter of the mounting nut is larger than the outer diameter of the outer nut, so that the position of the fixed base can be conveniently adjusted.

Furthermore, the mounting seat is in the shape of an inwards concave disc, a rubber ring is fixed in the mounting seat, and the rubber ring is used for fixing the soil pressure cell. The soil pressure cell is fixed through the rubber ring, and the position of the soil pressure cell in the mounting seat can be changed while the soil pressure cell is fixed, so that the soil pressure cell is protected.

Preferably, the supporting rod is a hollow rod piece, the bottom of the mounting seat is provided with a threading hole, and the threading hole is communicated with the cavity of the supporting rod; the mounting seat bottom is equipped with the threading groove, threading groove and through wires hole intercommunication, bracing piece cavity, through wires hole, threading groove are used for laying the cable of soil pressure cell. The cable of the soil pressure cell can be directly penetrated out through the support rod, the cable can be protected, and other structures do not need to be additionally arranged to penetrate out of the cable.

The invention also provides an installation method of the shield tunnel soil pressure box fixing device, which comprises the following steps:

assembling the soil pressure box fixing device body, and fixing the soil pressure box on the soil pressure box fixing device body;

fixedly connecting the mounting sleeve with the steel bars in the shield segment, plugging two ends of the mounting sleeve, and then pouring the shield segment in the shield segment template;

mounting a shield segment, and grouting a gap between the shield segment and surrounding rocks of the tunnel to form a segment wall post-grouting body;

taking out the end plug in the installation sleeve, drilling an installation channel in the duct piece wall back grouting body through the installation sleeve, drilling the installation channel to tunnel surrounding rocks, and grinding the tunnel surrounding rocks at the tail end of the installation channel to be flat;

installing a soil pressure cell fixing device body in an installation channel, connecting a cable of a soil pressure cell with a reading instrument, judging whether the soil pressure cell is completely contacted with tunnel surrounding rock or not by observing data change of the reading instrument, and then fixedly connecting a fixing base with an installation sleeve;

and grouting the installation sleeve and the installation channel to finish the fixed installation of the soil pressure cell.

Compared with the prior art, the invention has the following advantages and beneficial effects:

1. a fixing base is sleeved outside the supporting rod at the bottom end of the mounting seat, and the position of the fixing base in the length direction of the supporting rod is adjustable; when in use, the mounting seat is mounted in the duct piece wall back grouting body, so that the upper end of the soil pressure box is close to the tunnel surrounding rock; the fixed base is inserted in the shield pipe piece when in use and is fixedly connected with the shield pipe piece. After the shield segment and the segment wall post-grouting body are built, the soil pressure box is fixed through the soil pressure box fixing device body, the fixing base of the fixing device body is fixedly connected with the shield segment, and the position of the fixing base in the length direction of the support rod at the lower end of the mounting base is adjustable, so that the soil pressure box is directly contacted with the tunnel surrounding rock according to the set initial pressure. The damage of the grouting to the soil pressure cell can be avoided, and the influence of the grouting on the accuracy of the soil pressure cell measurement is avoided. Therefore, the error of the measuring result of the soil pressure cell is small, and the monitoring result can accurately reflect the soil pressure of the surrounding rock of the tunnel.

2. The grout stopping ring can prevent the grout poured after the installation of the device from overflowing to the positions of the soil pressure cell and the tunnel surrounding rock and influencing the measuring effect of the soil pressure cell.

3. The device is provided with threading groove and through wires hole, can directly wear out the cable through the bracing piece, need not increase other structures again and wears out the cable.

4. The device is fixed in the installation sleeve through the fixed base, has enough operation space and is simple and convenient to install.

5. After the device is installed, concrete is poured into the installation sleeve and the installation channel through the grouting holes, gaps are completely filled, and installation hole grouting bodies tightly bonded with the installation sleeve and the installation channel are formed. The integrality of the shield segment and the segment wall post-grouting body is repaired.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principles of the invention. In the drawings:

FIG. 1 is a schematic structural view of a soil pressure cell retaining apparatus according to the present invention;

FIG. 2 is a schematic top view of the earth pressure cell securing device of the present invention;

fig. 3 is a schematic view illustrating the installation of the soil pressure cell fixing device of the present invention.

Reference numbers and corresponding part names in the drawings:

1-soil pressure cell fixing device body, 2-shield segment, 3-segment wall post-grouting body, 4-tunnel surrounding rock, 5-mounting hole grouting body, 6-mounting seat, 7-threading hole, 8-threading groove, 9-rubber ring, 10-step, 11-fixing ring, 12-grout-stopping ring, 13-supporting rod, 14-fixing base, 15-internal nut, 16-mounting nut, 17-grout-stopping pad, 18-grouting hole, 19-external nut, 20-through hole, 21-soil pressure cell, 22-cable, 23-mounting sleeve and 24-mounting channel.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to examples and accompanying drawings, and the exemplary embodiments and descriptions thereof are only used for explaining the present invention and are not meant to limit the present invention.