阅读说明：本技术 高烈度地震活动断层区域的盾构隧道纵向接头结构 (Longitudinal joint structure of shield tunnel in high-intensity earthquake active fault area ) 是由 张中杰 张广超 杨波 王春凯 胡稳 殷文涛 于 2021-06-21 设计创作，主要内容包括：本发明公开了高烈度地震活动断层区域的盾构隧道纵向接头结构,包括若干螺杆；每一钢筋混凝土管片设置螺杆的位置从外向内均依次包括连通的锥形螺栓孔、螺栓手孔和螺栓安装导洞；每一锥形螺栓孔均为一端孔径大于另一端孔径的锥形孔；每一锥形螺栓孔孔径较大的一端的孔径均为孔径较小的一端的孔径的2倍以上；每一锥形螺栓孔与相应的螺杆之间均设有锥形橡胶套管；每一螺杆的两端,位于相应的螺栓手孔内的部分均通过螺母进行紧固,并均设有垫圈组；每一垫圈组均包括橡胶垫圈、弹簧,以及分别设置于弹簧两端,夹持弹簧的两片刚垫圈。本发明的应用令盾构隧道衬砌结构可以较好地适应地层变形,满足盾构隧道在易产生地层不均匀变形区域建设中的需求。(The invention discloses a shield tunnel longitudinal joint structure of a high-intensity earthquake active fault area, which comprises a plurality of screw rods; the position of each reinforced concrete segment provided with the screw sequentially comprises a conical bolt hole, a bolt hand hole and a bolt installation pilot hole from outside to inside; each conical bolt hole is a conical hole with the aperture of one end larger than that of the other end; the aperture of the end with the larger aperture of each conical bolt hole is more than 2 times of the aperture of the end with the smaller aperture; a conical rubber sleeve is arranged between each conical bolt hole and the corresponding screw; the parts of the two ends of each screw rod, which are positioned in the corresponding bolt hand holes, are fastened through nuts and are provided with gasket groups; each gasket group comprises a rubber gasket, a spring and two rigid gaskets which are respectively arranged at two ends of the spring and used for clamping the spring. The application of the invention ensures that the lining structure of the shield tunnel can better adapt to stratum deformation and meet the requirement of the shield tunnel in the construction of the area which is easy to generate uneven deformation of the stratum.)

1. The shield tunnel longitudinal joint structure of the high-intensity earthquake active fault area comprises a plurality of screw rods (8) which are axially arranged in parallel with reinforced concrete segments (1); each screw rod (8) is arranged between two adjacent reinforced concrete pipe pieces (1) and is used for connecting the two adjacent reinforced concrete pipe pieces (1); the method is characterized in that:

the position, where the screw (8) is arranged, of each reinforced concrete segment (1) sequentially comprises a conical bolt hole (3), a bolt hand hole (2) and a bolt installation pilot hole (5) which are communicated from outside to inside;

each conical bolt hole (3) is a conical hole with the aperture larger than that of the other end, the end with the larger aperture is positioned on the connecting surface of two adjacent reinforced concrete segments (1), and the end with the smaller aperture is connected with the bolt hand hole (2);

the aperture of the end with the larger aperture of each conical bolt hole (3) is more than 2 times of the aperture of the end with the smaller aperture;

a conical rubber sleeve (4) is arranged between each conical bolt hole (3) and the corresponding screw (8); the shape of each conical rubber sleeve (4) is matched with the inner hole of the corresponding conical bolt hole (3), and the inner hole is matched with the corresponding screw (8);

the parts, which are positioned in the corresponding bolt hand holes (2), of the two ends of each screw (8) are fastened through nuts (9) and are provided with gasket groups;

each gasket group comprises a rubber gasket (12), a spring (11) and two rigid gaskets (10) which are respectively arranged at two ends of the spring (10) and used for clamping the spring (10);

the rubber gasket (12), the spring (11) and the two steel gaskets (10) of each gasket set are sleeved at the end part of the corresponding screw rod (8) and are pressed on the surface, provided with the conical bolt hole (3), of the corresponding bolt hand hole (2) by the corresponding nut (9).

2. A shield tunnel longitudinal joint structure in high-intensity earthquake active fault areas according to claim 1, characterized in that a steel sleeve (6) is arranged in each bolt installation pilot hole (5).

3. The shield tunnel longitudinal joint structure of the high-intensity seismic active fault area according to claim 1, wherein the contact portions of the longitudinal joint portions of two adjacent reinforced concrete segments (1) are in a plane contact form.

4. The shield tunnel longitudinal joint structure of the high-intensity earthquake active fault area according to claim 1, wherein each reinforced concrete segment (1) is provided with an annular elastic rubber gasket (13) and a water retaining strip (14) from inside to outside on the outer sides of a plurality of screw rods (8).

5. The shield tunnel longitudinal joint structure of high-intensity seismic active fault area according to claim 1, characterized in that the width w of the water stopping groove (7) for installing the elastic rubber gasket (13) is w ═ w₀+d_l-d_s(ii) a Wherein, w₀The effective contact width of the sealing strip; d_lThe maximum diameter of the conical bolt hole (3); d_sIs the diameter of the screw (8).

Technical Field

The invention relates to the technical field of shield tunnel construction, in particular to a shield tunnel longitudinal joint structure of a high-intensity earthquake active fault area.

Background

In recent years, urban rail transit construction is very popular, and a shield tunnel is a tunnel structure form widely applied to urban subway construction. With the rapid development of urban subways, a plurality of new problems are exposed in the construction of shield tunnels. When the shield tunnel passes through an area such as an active fault and the like where local stratum differential settlement is generated, the situation that the longitudinal connecting bolts and the segments are locally damaged due to the action of dislocation, tensile deformation and seismic load between adjacent lining rings occurs.

State of the art related art:

the conventional shield tunnel is provided with a longitudinal bolt hole at the longitudinal joint of the segment, the longitudinal connection of adjacent lining rings is realized by steel bolts, nuts are adopted at two ends of the bolts for screwing, steel gaskets are arranged on the inner sides of the nuts, and the hole diameter of the bolt hole is generally slightly larger than the diameter of the bolt (about 4-6 mm). When adjacent rings of lining are stretched or dislocated with formation deformation, they tend to cause the longitudinal connecting bolts to be pulled apart or sheared off by the bolt holes and local damage to the concrete segment. The problems not only reduce the safety of the structure, but also cause serious water leakage of the shield tunnel due to the dislocation of the water stop belts or insufficient extrusion force.

In view of the above problems, existing solutions can be mainly classified into three categories: flexible grouting, flexible duct piece and flexible joint.

The flexible grouting method adopts flexible materials such as rubber or light cement paste and the like as the grouting materials behind the wall of the shield tunnel, and the flexible grouting materials can reduce the influence of stratum deformation on the shield tunnel structure through self deformation. However, the method has high material cost, requires a large overbreak range in the shield tunnel construction process, increases the construction difficulty, and has limited effect on the condition of large stratum deformation, particularly tensile deformation.

The flexible duct piece method generally adopts a mixed duct piece formed by combining a steel pipe piece or a steel plate with concrete, a spring or a damping material is arranged in the duct piece, the duct piece is allowed to generate a certain amount of deformation along with a stratum, but the duct piece has higher manufacturing cost, complex production process and poorer shearing deformation effect.

The flexible joint method generally adopts a method of adding a spring on the basis of the traditional bolt or adopting a memory alloy plate with certain deformability at the segment joint position to replace the bolt as a connecting piece. The method is relatively simple to operate and low in manufacturing cost, but the existing method is difficult to simultaneously meet the deformation of the lining structure in the stretching and shearing directions.

In the prior art, unbalanced forces in the longitudinal direction of the shield tunnel lining structure are mainly transmitted by means of longitudinal joints. However, in high-intensity earthquake regions and regions where active faults exist, acting forces generated by relative displacement of strata and earthquake loads are extremely complex, and a longitudinal joint is always subjected to large shearing force and tensile force.

The existing longitudinal joint of the shield tunnel segment lining has limited shear resistance and tensile deformation resistance, and joint bolts and lining structures are easily damaged during earthquake.

For example, osaka earthquake in 1995 causes significant damage to the longitudinal joints of a large number of shield tunnels, making the tunnels unusable.

In the ground of Wenchuan in 2008, a large dislocation occurs at a plurality of section shield tunnel longitudinal joints of a Chengdu subway, and duct pieces crack occurs near the longitudinal joints.

Therefore, in the shield tunnel in the high-intensity earthquake area, the longitudinal joint is the weakest link of the shield tunnel segment lining, and the shock resistance of the longitudinal joint is to be improved.

Therefore, how to effectively satisfy the deformation of the lining shield tunnel masonry structure in the stretching and shearing directions at the same time becomes a technical problem which needs to be solved urgently by the technical personnel in the field.

Disclosure of Invention

In view of the defects in the prior art, the invention provides the longitudinal joint structure of the shield tunnel in the high-intensity earthquake active fault area, and aims to enable the lining structure of the shield tunnel to better adapt to stratum deformation, meet the requirement of the shield tunnel in the construction of the area which is easy to generate uneven stratum deformation, and improve the safety, durability and economy of the shield tunnel.

In order to achieve the purpose, the invention discloses a shield tunnel longitudinal joint structure of a high-intensity earthquake active fault area, which comprises a plurality of screw rods axially arranged in parallel with reinforced concrete segments; each screw rod is arranged between two adjacent reinforced concrete segments and used for connecting the two adjacent reinforced concrete segments.

The position, where the screw is arranged, of each reinforced concrete segment sequentially comprises a conical bolt hole, a bolt hand hole and a bolt installation pilot hole from outside to inside, which are communicated with each other;

each conical bolt hole is a conical hole with the aperture larger than that of the other end at one end, the end with the larger aperture is positioned on the connecting surface of two adjacent reinforced concrete segments, and the end with the smaller aperture is connected with the bolt hand hole;

the aperture of the end with the larger aperture of each conical bolt hole is more than 2 times of the aperture of the end with the smaller aperture;

a conical rubber sleeve is arranged between each conical bolt hole and the corresponding screw; the shape of each conical rubber sleeve is matched with the inner hole of the corresponding conical bolt hole, and the inner hole is matched with the corresponding screw;

the parts, located in the corresponding bolt hand holes, of the two ends of each screw rod are fastened through nuts, and are provided with gasket groups;

each gasket group comprises a rubber gasket, a spring and two rigid gaskets which are respectively arranged at two ends of the spring and used for clamping the spring;

the rubber washer, the spring and the two steel washers of each washer set are sleeved at the end part of the corresponding screw rod and are pressed tightly on the surface of the corresponding bolt hand hole provided with the conical bolt hole by the corresponding nut.

Preferably, a steel sleeve is arranged in each bolt installation guide hole.

Preferably, the contact portions of the longitudinal joint portions of two adjacent reinforced concrete segments are in a plane contact form.

Preferably, each reinforced concrete segment is provided with annular elastic rubber sealing gaskets and water retaining strips from inside to outside and positioned at the outer sides of the plurality of screw rods.

Preferably, the width w of the water stop groove to which the elastic rubber packing is attached is w₀+d_l-d_s(ii) a Wherein, w₀The effective contact width of the sealing strip; d_lThe maximum diameter of the conical bolt hole; d_sIs the diameter of the screw.

The invention has the beneficial effects that:

according to the invention, when adjacent pipe pieces are dislocated within a certain range, the longitudinal connecting bolt cannot be sheared and damaged, and meanwhile, the width of the elastic water stop strip is increased, so that the waterproof failure caused by the dislocated adjacent pipe pieces is avoided.

The rubber gasket is arranged in the gasket group, and when the stratum deforms along the longitudinal direction of the shield tunnel, the rubber gasket can reduce the damage of stratum deformation to rigid members such as bolts, pipe pieces and the like through self compression deformation.

The conical rubber sleeve and the spring arranged at the segment joint increase the flexibility of the shield tunnel in the direction vertical to the axis and in the longitudinal direction, and improve the capacity of the whole shield tunnel for resisting shock load.

The invention has simple structure and easy realization, and can be conveniently applied to various shield tunnels by using the prior shield tunnel construction technology and equipment.

The conception, the specific structure and the technical effects of the present invention will be further described with reference to the accompanying drawings to fully understand the objects, the features and the effects of the present invention.

Drawings

Fig. 1 shows a schematic structural diagram of an embodiment of the present invention.

Fig. 2 is a schematic partial sectional structure diagram illustrating a position of a screw rod of a reinforced concrete segment according to an embodiment of the present invention.

Fig. 3 shows a schematic structural diagram of a tapered rubber bushing according to an embodiment of the present invention.

Fig. 4 is a schematic diagram showing a partial enlarged structure at AA in fig. 3 according to the present invention.

Fig. 5 shows a schematic diagram of the present invention at a part BB in fig. 3.

Fig. 6 is a schematic structural diagram of a nut and washer set arranged at two ends of a screw according to an embodiment of the present invention.

Detailed Description

Examples

As shown in fig. 1 to 6, the shield tunnel longitudinal joint structure of the high-intensity earthquake active fault area comprises a plurality of screw rods 8 which are arranged in parallel with the axial direction of the reinforced concrete segment 1; each screw 8 is arranged between two adjacent reinforced concrete segments 1 and used for connecting the two adjacent reinforced concrete segments 1.

Wherein, the position of each reinforced concrete segment 1 provided with the screw 8 sequentially comprises a conical bolt hole 3, a bolt hand hole 2 and a bolt installation pilot hole 5 which are communicated from outside to inside;

each conical bolt hole 3 is a conical hole with the aperture larger at one end than the aperture at the other end, the end with the larger aperture is positioned on the connecting surface of two adjacent reinforced concrete segments 1, and the end with the smaller aperture is connected with the bolt hand hole 2;

the aperture of the end with the larger aperture of each conical bolt hole 3 is more than 2 times of the aperture of the end with the smaller aperture;

a conical rubber sleeve 4 is arranged between each conical bolt hole 3 and the corresponding screw 8; the shape of each conical rubber sleeve 4 is matched with the inner hole of the corresponding conical bolt hole 3, and the inner holes are matched with the corresponding screw rods 8;

the parts of the two ends of each screw 8, which are positioned in the corresponding bolt hand holes 2, are fastened through nuts 9 and are provided with gasket groups;

each gasket group comprises a rubber gasket 12, a spring 11 and two rigid gaskets 10 which are respectively arranged at two ends of the spring 10 and used for clamping the spring 10;

the rubber washer 12, the spring 11 and the two steel washers 10 of each washer set are sleeved on the end part of the corresponding screw 8 and are pressed on the surface of the corresponding bolt hand hole 2 provided with the conical bolt hole 3 by the corresponding nut 9.

The principle of the invention is as follows:

the hole that sets up screw rod 8 adopts the structure of toper bolt hole 3, and when adjacent reinforced concrete section of jurisdiction 1 took place the dislocation in the certain limit, screw rod 8 can not take place to cut and destroy. Meanwhile, the width of the elastic water stop strip is increased, and waterproof failure caused by dislocation of adjacent reinforced concrete segments 1 is avoided.

By the measures, the shield tunnel lining structure can generate deformation along the radial direction of the tunnel and deformation along the axial direction of the tunnel at the longitudinal joint. Meanwhile, due to the arrangement of the spring 11, the rubber gasket 12 and the conical rubber sleeve 4, the overall flexibility of the structure is increased, and the capability of the shield tunnel for bearing earthquake loads can be effectively improved.

Moreover, because the deformation of the active fault is accompanied by the earthquake, the flexibility of the structure is improved, and the capability of resisting the earthquake load can be effectively enhanced.

The method comprises the following specific steps:

let d_s-represents the screw diameter, d_lRepresenting the maximum diameter of the trumpet bolt hole. The maximum dislocation distance before shearing damage of longitudinal connecting bolts is caused when adjacent segments are dislocated:

Δ＝d_l-d_s。

because set up the rubber packing ring in the packing ring, when the section of jurisdiction dislocation, the screw rod can produce around the rotation of screw rod vertical direction in the packing ring position, avoids the screw rod to produce great concentrated stress in the bolt position, and then produces the hidden danger of destruction.

Due to the existence of the rubber gasket, when the stratum deforms along the longitudinal direction of the shield tunnel, the damage of stratum deformation to rigid members such as bolts and pipe pieces can be reduced through the compression deformation of the stratum.

Let L_s-represents the effective length of the bolt; a. the_s-represents the bolt cross-sectional area; e_s-representational boltThe modulus of elasticity of (a); k represents the stiffness coefficient of the spring; assuming that the longitudinal relative displacement of the two segments of the longitudinal joint is delta, the tension F borne by the bolts of the conventional joint₀＝ΔE_sA_s/L_sThe tensile force F ═ Delta E born by the bolt of the rear joint applying the invention_sA_s/(L_s+2E_sA_s/k)。

In some embodiments, a steel sleeve 6 is disposed within each bolt installation guide hole 5.

In some embodiments, the contact portions of the longitudinal joint locations of two adjacent reinforced concrete segments 1 are in the form of planar contact.

In some embodiments, each reinforced concrete segment 1 is provided with an annular elastic rubber sealing gasket 13 and a water retaining strip 14 from inside to outside on the outer sides of the plurality of screw rods 8.

In one embodiment, the width w of the water stop groove 7 to which the elastic rubber packing 13 is attached is w₀+d_l-d_s(ii) a Wherein, w₀The effective contact width of the sealing strip; d_lThe maximum diameter of the conical bolt hole 3; d_sThe diameter of the screw 8.

In actual assembly, firstly, an elastic rubber sealing gasket 13 and a water retaining strip 14 are adhered at the positions shown in fig. 1 and fig. 2, a screw 8 is inserted into a bolt installation pilot hole of a concrete segment on one side, then longitudinal bolt holes of adjacent shield segment lining rings are aligned, the screw passes through two adjacent conical bolt holes 3, finally, a rubber gasket 12, a rigid gasket 10, a spring 11, a rigid gasket 10 and a nut 9 are sequentially sleeved on two sides of the screw according to the sequence shown in fig. 3, and the tight nut is rotated to realize the assembly between the adjacent concrete segments.

The basic parameter is the modulus of elasticity E of the bolt 8_sLength L of bolt 8 of 210GPa_s0.62m, diameter d of bolt 8_s36mm, cross-sectional area A_s＝0.001018m²。

Assuming that the shield tunnel is deformed in the longitudinal direction, the distance delta of the joint is 2 mm. The prior art longitudinal joint setting method, the additional tension to which the bolt is subjected:

when the longitudinal joint of the invention is used, the stiffness coefficient k of the spring 11 is 1 x 10⁸N/m, tensile force borne by the bolt 8:

therefore, when the longitudinal joint of the shield tunnel deforms along the axis direction of the tunnel for a certain time, the additional tensile force of the bolt generated by the invention is far smaller than that of the prior art, the capability of the structure for resisting longitudinal deformation is obviously improved, and the capability of the shield tunnel for longitudinal earthquake load is also improved.

Assuming that the longitudinal joint position of the shield tunnel is relatively deformed along the tangential direction, the diameter d of the bolt hole in the prior art_k40mm, then when the bolt did not take place to cut and destroy, the biggest wrong platform volume of adjacent section of jurisdiction is:

Δ₀≈d_k-d_s＝4mm

when the longitudinal joint is adopted, the maximum diameter d of the cross section of the conical bolt hole 3 is taken_lWhen the bolt 8 is not sheared and damaged, the maximum slab staggering amount of the adjacent reinforced concrete segment 1 is as follows:

Δ₀≈d_l-d_s＝36mm

the method provided by the patent can effectively improve the capability of the lining structure of the shield tunnel adapting to the deformation of the stratum in the direction vertical to the axis, and simultaneously improves the capability of the whole structure resisting the seismic load in the direction vertical to the axis due to the enhancement of the flexibility of the shield tunnel in the direction.

In practical application, the tangential relative displacement generated by the corresponding joint within the service life of the shield tunnel can be estimated according to the width and the relative movement rate of the fault zone, and the maximum diameter d of the cross section of the conical bolt hole 3 is set according to the tangential relative displacement_l。

The foregoing detailed description of the preferred embodiments of the invention has been presented. It should be understood that numerous modifications and variations could be devised by those skilled in the art in light of the present teachings without departing from the inventive concepts. Therefore, the technical solutions available to those skilled in the art through logic analysis, reasoning and limited experiments based on the prior art according to the concept of the present invention should be within the scope of protection defined by the claims.