CN208121552U - A kind of reverse increasing layer construction underpinning structure in overpass pier base underground - Google Patents

Abstract

The utility model provides an underpinning structure for reverse layer-increasing underground construction of viaduct pier foundations, comprising: an enclosure structure and engineering piles arranged in the underground space below the viaduct, a basement roof beam arranged on the engineering piles, and a basement roof beam arranged on the engineering piles. The underpinning temporary structure above, and the hydraulic jack installed between the underpinning temporary structure and the viaduct for actively underpinning the viaduct, the top extension of the hydraulic jack is fixedly connected with the viaduct, and the underpinning temporary structure includes two For the support beams arranged in parallel and several support columns for supporting the support beams, the lower ends of the support columns are fixedly connected to the basement roof beams, the support beams are parallel to the longitudinal direction of the viaduct, and each pair of support beams is arranged on the viaduct column on both sides. The hydraulic jack continuously compensates the underpinning and load settlement deformation of the viaduct, eliminates the uneven deformation and settlement of the viaduct during the development and construction of the underground space, and ensures the normal operation of the viaduct during the construction of underground layer addition.

Description

An underpinning structure for underground reverse layer-adding construction of viaduct pier foundation

technical field

The utility model relates to an underground layer-increasing method for elevated column pier foundations, which is especially suitable for the underground layer-increasing method for elevated column pier foundations in an operating state.

Background technique

At present, the development and utilization of urban underground space has become a new direction for urban renewal and development. While the underground space of new construction projects is facing large-scale, deep-level, and comprehensive development, the absence of underground space in existing buildings has gradually become a problem that affects urban development. short board.

For example, many important transportation hubs, large venues and residential areas have problems such as parking difficulties. These problems have become increasingly prominent and have seriously affected the sustainable development of cities.

In the process of underground space development and utilization, often due to planning requirements and road conditions, some underground space development sidelines cross the projection line of the viaduct in operation, which will involve the development of underground space under the viaduct in the operating state. High-risk problems in the construction of underground layer additions to pier foundations.

Utility model content

The purpose of the utility model is to provide an underpinning structure for the underground reverse layer increase construction of the viaduct pier foundation, which solves the problem that the settlement deformation of the viaduct affects the safe operation of the viaduct in the process of underground reverse layer increase of the viaduct pier foundation, and at the same time solves the problem of Settlement deformation of reconstructed permanent viaduct columns on newly developed basement roof.

In order to solve the above technical problems, the utility model provides the following technical solutions:

An underpinning structure for underground reverse layer-adding construction of viaduct column pier foundations, comprising:

The enclosure structure and engineering piles installed in the underground space under the viaduct, the basement roof beams installed on the engineering piles, the underpinning temporary structures installed on the basement roof beams, and the underpinning temporary structures installed between the viaducts It is used to actively underpin the hydraulic jack of the elevated bridge, the top extension of the hydraulic jack is fixedly connected with the elevated bridge, and the underpinning temporary structure includes two pairs of supporting beams arranged in parallel and several supports for supporting the supporting beams The lower end of the support column is fixedly connected to the basement roof beam, the support beam is parallel to the longitudinal direction of the viaduct, and each pair of support beams is arranged on both sides of the viaduct column.

Preferably, in the underpinning structure of the above-mentioned viaduct column pier foundation underground reverse layer-adding construction, the position of the supporting column installed on the basement roof beam is pre-embedded for installing the embedded part of the supporting column, and the lower end of the supporting column is connected to the basement roof beam The embedded parts on it are connected.

Preferably, in the above-mentioned viaduct pier foundation underground reverse layer construction underpinning structure, a limit device is installed between the viaduct and the supporting beam corresponding to each hydraulic jack, and the limiting device can limit the viaduct and the supporting beam. The relative horizontal displacement between them, the limit device is distributed around the hydraulic jack.

Preferably, in the underpinning structure of the above-mentioned underground reverse layer-adding construction of viaduct pier foundation, the limiting device includes a pre-embedded plate and an upper limiting member installed under the embedded plate, and the lower limiting member is fixedly arranged on the On the support beam, the lower limiter forms a groove for the upper limiter to extend into, the height of the upper limiter is smaller than the depth of the groove, and the embedded plate can rest on the lower limiter .

Preferably, in the underpinning structure of the above-mentioned underground reverse layer-adding construction of viaduct pier foundations, the lower limiting member includes four right-angled trapezoidal wedge blocks evenly distributed around the hydraulic jack, and the upper limiting member includes four A right-angled trapezoidal wedge, the right-angled waist of the right-angled trapezoidal wedge of the upper limiter is opposite to the right-angled waist of the right-angled trapezoidal wedge of the lower limiter.

Preferably, in the underpinning structure of the underground reverse layer-adding construction of the viaduct column pier foundation, the support column and the viaduct column are arranged staggered along the longitudinal direction of the viaduct.

Preferably, in the underpinning structure of the above-mentioned viaduct column pier foundation underground reverse layer-adding construction, the hydraulic jack is a double-acting jack.

Preferably, in the above-mentioned reverse construction underpinning structure of the viaduct column pier foundation, several pairs of hydraulic steel pipe braces are arranged between the support beam and the basement roof beam, and each pair of hydraulic steel pipe braces is located on both sides of the corresponding viaduct column , each pair of hydraulic steel pipe braces and the corresponding viaduct columns are set along the transverse direction of the viaduct.

Preferably, in the underpinning structure of the above-mentioned underground reverse layer-adding construction of viaduct pier foundation, the hydraulic steel pipe support includes a steel pipe fixed end, a steel pipe support cylinder, two hydraulic jacks and a steel pipe telescopic end arranged in sequence from top to bottom , one end of the two hydraulic jacks is connected to the steel pipe support cylinder, and the other end is connected to the telescopic end of the steel pipe, the telescopic end of the steel pipe is fixedly connected to the basement roof beam, and the fixed end of the steel pipe is fixedly connected to the support beam .

Preferably, in the underpinning structure of the above-mentioned underground reverse build-up construction of the viaduct pier foundation, the enclosure structure includes enclosure piles and a water-stop curtain arranged outside the enclosure piles.

It can be seen from the technical solutions disclosed above that, compared with the prior art, the beneficial effects of the utility model are as follows:

The utility model provides the underpinning structure for the underground reverse layer-adding construction of the viaduct pier foundation. By setting the underpinning temporary structure and the hydraulic jack, the hydraulic jack is installed between the underpinning temporary structure and the viaduct for active underpinning of the viaduct. The top protruding end of the hydraulic jack is fixedly connected with the viaduct, and the underpinning temporary structure includes two pairs of supporting beams arranged in parallel and several supporting columns for supporting the supporting beams, and the lower ends of the supporting columns are connected to the basement roof. The beams are fixedly connected, the support beams are parallel to the longitudinal direction of the viaduct, and each pair of support beams is arranged on both sides of the viaduct columns. During the construction process, the hydraulic jacks are used to continuously compensate the settlement deformation of the viaduct underpinning under load, and eliminate the underpinning of the viaduct. The uneven deformation and settlement in the development and construction of the underground space can ensure the normal operation of the viaduct during the construction of the underground layer addition. In addition, the newly developed underground space structure was used as the basis of the temporary underpinning system for this underpinning and layer increase, which saved a lot of underpinning pile foundations. Furthermore, by using this method of underpinning, the newly developed basement roof can be used as the permanent foundation of the viaduct column, reducing the pile foundation and cap of the viaduct column, and at the same time, it can make the column distance of the axis network in the underground space larger and the usable space more efficient. broad.

The utility model provides an underpinning structure for reverse layer-adding underground construction of viaduct pier foundations. By setting several pairs of hydraulic steel pipe braces between the support beam and the basement roof beam, each pair of hydraulic steel pipe braces is located on both sides of the corresponding viaduct column. Each pair of hydraulic steel pipe braces and the corresponding viaduct columns are arranged along the transverse direction of the viaduct. Before the hydraulic steel pipe braces are rebuilt on the viaduct columns, the hydraulic steel pipe braces are used to replace the underpinning temporary structure to support the viaduct bridge. The expansion and contraction of the hydraulic steel pipe braces The action compensates the viaduct settlement deformation caused by the deflection deformation after the viaduct load acts on the basement roof beam, so that the viaduct remains within the safe settlement deformation range, and then rebuilds the viaduct column. Since the support position of the basement roof girder for each pair of hydraulic steel pipe braces is as close as possible to the support position of the basement roof girder for the reconstructed viaduct columns, the settlement of the viaduct caused by the deflection deformation of the viaduct load after the reconstruction is applied to the basement roof girder The deformation is small, thereby effectively reducing the settlement displacement of the viaduct after the construction of the underground layer addition, and ensuring the normal operation of the viaduct.

Description of drawings

Fig. 1 is the schematic plan view of the underpinning structure in step 1-1 of the underpinning construction of the viaduct pier foundation underground in an embodiment of the utility model;

Fig. 2 is a schematic diagram of the longitudinal elevation of the underpinning structure of the viaduct pier foundation underground reverse layer increase construction in step 1-1 according to an embodiment of the present invention;

Fig. 3 is a schematic diagram of the horizontal elevation of the underpinning structure in step 1-1 of the underpinning construction of the viaduct pier foundation in an embodiment of the present invention;

Fig. 4 is a schematic diagram of the longitudinal elevation of the underpinning structure in steps 1-2 of the underpinning construction of the viaduct column pier foundation in an embodiment of the present invention;

Fig. 5 is a schematic diagram of the horizontal elevation of the underpinning structure in steps 1-2 of the underpinning construction of the viaduct pier foundation in an embodiment of the present invention;

6 is a schematic plan view of the underpinning structure in steps 1-4 of the underpinning construction of the viaduct pier foundation in an embodiment of the present invention;

Fig. 7 is a schematic diagram of the vertical elevation of the underpinning structure of the viaduct pier foundation underground reverse layer increase construction in steps 1-4 according to an embodiment of the present invention;

Fig. 8 is a schematic diagram of the horizontal elevation of the underpinning structure in steps 1-4 of the underpinning construction of the viaduct pier foundation in an embodiment of the present invention;

Fig. 9 is a schematic plan view of the underpinning structure in steps 1-5 of the underpinning construction of the viaduct column pier foundation in an embodiment of the present invention;

Fig. 10 is a schematic diagram of the vertical elevation of the underpinning structure of the viaduct pier foundation underground reverse layer increase construction in steps 1-5 according to an embodiment of the present invention;

Fig. 11 is a schematic diagram of the horizontal elevation of the underpinning structure in steps 1-5 of the underpinning construction of the viaduct pier foundation in an embodiment of the present invention;

Fig. 12 is a schematic diagram of the longitudinal elevation of the underpinning structure of the viaduct pier foundation underground reverse layer increase construction in steps 1-6, that is, the structural representation of the viaduct column pier foundation underground reverse layer increase construction underpinning structure;

Fig. 13 is a schematic diagram of the horizontal elevation of the underpinning structure in steps 1-6 of the underpinning construction of the viaduct column pier foundation in an embodiment of the present invention;

Fig. 14 is a schematic diagram of the longitudinal elevation of the underpinning structure in step 2-1 of the underpinning construction of the viaduct column pier foundation in an embodiment of the present invention;

Fig. 15 is a schematic diagram of the horizontal elevation of the underpinning structure in step 2-1 of the underpinning construction of the viaduct column pier foundation in an embodiment of the present invention;

Fig. 16 is a schematic diagram of the longitudinal elevation of the underpinning structure in step 3-1 of the underpinning construction of the viaduct column pier foundation in an embodiment of the present invention;

Fig. 17 is a schematic diagram of the horizontal elevation of the underpinning structure in step 3-1 of the underpinning construction of the viaduct column pier foundation in an embodiment of the present invention;

Fig. 18 is a schematic diagram of the longitudinal elevation of the underpinning structure in step 3-2 of the underpinning construction of the viaduct column pier foundation in an embodiment of the present invention;

Fig. 19 is a schematic diagram of the horizontal elevation of the underpinning structure in step 3-2 of the underpinning construction of the viaduct column pier foundation in an embodiment of the present invention;

Fig. 20 is a schematic diagram of the longitudinal elevation of the underpinning structure in step 3-3 of the underpinning construction of the viaduct column pier foundation in an embodiment of the present invention;

Fig. 21 is a schematic diagram of the horizontal elevation of the underpinning structure in step 3-3 of the underpinning construction of the viaduct column pier foundation in an embodiment of the present invention;

Fig. 22 is a schematic structural view of a limiting device in an embodiment of the present invention;

Fig. 23 is a schematic cross-sectional view of A-A of Fig. 22;

In the figure: 1- viaduct column, 2- viaduct bridge, 3- engineering pile, 4- basement roof beam, 5- hydraulic jack, 6- support beam, 7- support column, 8- hydraulic steel pipe support, 9- enclosure pile , 10-waterproof curtain, 11-limiting device, 111-embedded plate, 112-upper limit piece, 113-lower limit piece, 12-basement floor structure beam plate, 13-elevated column pier.

Detailed ways

Below in conjunction with accompanying drawing and specific embodiment the utility model is described in further detail. According to the following description and claims, the advantages and features of the utility model will be more clear. The technical contents and features of the present utility model will be described in detail below by referring to the enumerated embodiments in conjunction with the accompanying drawings. It should be further noted that all the drawings are in very simplified form and use inaccurate scales, which are only used to facilitate and clearly assist the purpose of illustrating the embodiments of the present utility model. For the convenience of description, the "up" and "down" described below are consistent with the directions of up and down in the drawings, but this cannot be a limitation of the technical solution of the present utility model.

Please refer to Figure 16, and please refer to Figures 1 to 15 and Figures 17 to 23 in combination. This embodiment provides an underpinning structure for underground reverse layer addition construction of viaduct column pier foundations, which is used for underground reverse layer addition construction of viaduct column pier foundations. . The viaduct includes a viaduct column 1 and a viaduct 2 supported by the viaduct column 1 . The underpinning structure of the underground reverse layer-adding construction of the viaduct pier foundation includes: an enclosure structure and engineering piles 3 arranged in the underground space below the viaduct, a basement roof beam 4 arranged on the engineering pile, and a supporting structure arranged on the basement roof beam. Replace the temporary structure, and install the hydraulic jack 5 for actively underpinning the viaduct 2 between the underpinning temporary structure and the viaduct 2, the top extension of the hydraulic jack is fixedly connected with the viaduct, and the underpinning The temporary structure includes two pairs of supporting beams 6 arranged in parallel and several supporting columns 7 for supporting the supporting beams 6, the lower ends of the supporting columns 7 are fixedly connected with the basement roof beam 4, and the supporting beams 6 are connected with the viaduct Each pair of supporting beams 6 is arranged on both sides of the viaduct column 1. The enclosure structure includes an enclosure pile 9 and a water-stop curtain 10 arranged outside the enclosure pile 9 .

The utility model provides the underpinning structure for the underpinning construction of the viaduct column pier foundation in the reverse direction, by setting the underpinning temporary structure and the hydraulic jack 5, and the hydraulic jack 5 is installed between the underpinning temporary structure and the viaduct 2 for actively underpinning the viaduct Beam 2, the top protruding end of the hydraulic jack 5 is fixedly connected to the viaduct 2, and the hydraulic jack is used to continuously compensate the viaduct 2 underpinning and settlement deformation under load during the construction process, so as to eliminate the viaduct 2 during the development and construction of the underground space. Uneven deformation and settlement ensure that the viaduct 2 can operate normally during the construction of underground layer addition. In addition, the newly developed underground space structure was used as the basis of the temporary underpinning system for this underpinning and layer increase, which saved a lot of underpinning pile foundations. Furthermore, by using this method of underpinning, the newly developed basement roof can be used as the permanent foundation of the viaduct column 1, reducing the pile foundation and cap of the viaduct column 1, and at the same time, the column spacing of the grid in the underground space can be made larger. The space is wider.

In order to improve the connection strength between the support column and the basement roof beam, preferably, in the above-mentioned viaduct column pier foundation underground reverse layer construction underpinning structure, the position of the support column installed on the basement roof beam 4 is pre-buried for installation support The embedded part of the column 7, the lower end of the supporting column 7 is connected with the embedded part on the roof beam 4 of the basement.

In order to ensure the stability of the viaduct 2 in the construction of the underground layer increase and ensure its normal operation, preferably, in the above-mentioned underpinning structure for the underground reverse layer increase construction of the viaduct pier foundation, between the viaduct 2 and the support beam 6 A limit device 11 is installed corresponding to each hydraulic jack 5 , and the limit device 11 can limit the relative horizontal displacement between the viaduct 2 and the support beam 6 , and the limit device 11 is distributed around the hydraulic jack 5 .

Preferably, the limiting device 11 includes an embedded board 111 and an upper limiting member 112 installed under the embedded board 111, the lower limiting member 113 is fixedly arranged on the support beam 6, and the lower limiting member 113 A groove is formed for the upper limit member 112 to protrude into. The height of the upper limit member 112 is smaller than the depth of the groove, and the embedded plate 111 can rest on the lower limit member 113 . The upper limiter 112 is always located in the groove of the lower limiter 113 , so as to limit the horizontal displacement of the viaduct 2 relative to the support beam 6 .

In this embodiment, in the underpinning structure of the above-mentioned underground reverse layer-adding construction of viaduct pier foundation, the lower limit member 113 includes four right-angled trapezoidal wedge blocks evenly distributed around the hydraulic jack 5, and the upper limit The piece 112 includes four right-angled trapezoidal wedges, and the right-angled waist of the right-angled trapezoidal wedge of the upper limiter 112 is opposite to the right-angled waist of the right-angled trapezoidal wedge of the lower limiter 113 . The right-angled waist of the right-angled trapezoidal wedge of the upper limiter 112 can only move up and down relative to the right-angled trapezoidal wedge of the lower limiter 113, so that the viaduct 2 fixedly connected with the upper limiter 112 cannot be opposite to the lower limiter. 113 The fixedly connected support beam 6 moves horizontally and tilts, so as to ensure the normal operation of the viaduct 2 .

Preferably, in the underpinning structure of the above-mentioned viaduct column pier foundation underground reverse layer-adding construction, the support column 7 and the viaduct column 1 are arranged staggered along the longitudinal direction of the viaduct.

Preferably, in the underpinning structure of the above-mentioned viaduct column pier foundation underground reverse layer-adding construction, the hydraulic jack 5 is a double-acting jack.

Preferably, in the above-mentioned viaduct pier foundation underground reverse layer construction underpinning structure, several pairs of hydraulic steel pipe braces 8 are arranged between the support beam 6 and the basement roof beam 4, and each pair of hydraulic steel pipe braces 8 is located on the corresponding viaduct bridge. On both sides of the column 1, each pair of hydraulic steel pipe braces 8 and the corresponding viaduct column 1 are arranged along the transverse direction of the viaduct. By setting several pairs of hydraulic steel pipe braces 8 between the support beam 6 and the basement roof beam 4, each pair of hydraulic steel pipe braces 8 is located on both sides of the corresponding viaduct column 1, and each pair of hydraulic steel pipe braces and the corresponding viaduct column 1 are along the For the horizontal setting of the viaduct, before the hydraulic steel pipe brace 8 is rebuilt on the viaduct column 1, the hydraulic steel pipe brace 8 is used to replace the underpinning temporary structure to support the viaduct 2, and the expansion and contraction of the hydraulic steel pipe brace 8 ensures that the viaduct 2 is located The height of the design allows the basement roof to be deformed in advance, and then the viaduct column 1 is reconstructed. Since the support position of the basement roof beam 4 for each pair of hydraulic steel pipe braces 8 is as close as possible to the support position of the basement roof beam 4 for the reconstructed viaduct column 1, therefore, the viaduct load acts on the rear deflection deformation of the basement roof beam after reconstruction The resulting settlement and deformation of the viaduct is small, thereby effectively reducing the settlement displacement of the viaduct 2 after the construction of the underground layer addition, and ensuring the normal operation of the viaduct 2 .

Specifically, in the underpinning structure of the underground reverse layer-adding construction of the viaduct pier foundation in this embodiment, the hydraulic steel pipe brace includes a steel pipe fixed end, a steel pipe support cylinder, two hydraulic jacks and Steel pipe telescopic end, one end of the two hydraulic jacks is connected to the steel pipe support cylinder, the other end is connected to the steel pipe telescopic end, the steel pipe telescopic end is fixedly connected to the basement roof beam, and the steel pipe fixed end is connected to the support The beam is fixedly connected.

Please refer to Figures 1 to 23. This embodiment discloses a method for using an underpinning structure for underground reverse layer-adding construction of viaduct column pier foundations, which is used for underground reverse layer-addition construction of viaduct column pier foundations. The viaduct column pier foundations are underground The underpinning structure of reverse build-up construction includes:

Step 1, construct the underground space enclosure structure, engineering piles 3 and basement roof beam 4 under the elevated, erect a temporary underpinning structure on the basement roof beam 4, install a hydraulic jack 5 on the underpinning temporary structure, and actively underpin the elevated bridge 2. The top protruding end of the hydraulic jack 5 is fixedly connected to the viaduct 2, and the underpinning temporary structure includes two pairs of supporting beams 6 arranged in parallel and several supporting columns 7 for supporting the supporting beams 6. The lower ends of the support columns 7 are fixedly connected to the basement roof beams 4, the support beams 6 are parallel to the longitudinal direction of the viaduct, and each pair of support beams 6 is arranged on both sides of the viaduct columns 1 .

Step 2: After the underpinning of the viaduct 2 is completed, excavate the foundation of the viaduct column 1, excavate the basement in reverse, complete the main structure of the basement, and fill in the basement roof beam 4 to form the basement roof. During the construction process, use the hydraulic jack 5 to lift Adjust the deformation stress of the viaduct 2 by using oil return shrinkage to ensure that the viaduct 2 is in a safe operation state during the underground space development stage.

Step 3, install hydraulic steel pipe braces 8 between the basement roof beam 4 and the support beam 6, the top extension end of the hydraulic steel pipe brace 8 is fixedly connected to the part of the support beam 6 close to the corresponding elevated column 1, and the 8 pairs of hydraulic steel pipe braces The viaduct 2 is underpinned twice, and the viaduct column 1 is rebuilt on the roof of the newly developed basement to eliminate the settlement deformation caused by the viaduct 2 rebuilding the permanent viaduct column 1 on the basement roof.

The utility model provides the underpinning structure for the underground reverse layer-adding construction of the viaduct pier foundation. The viaduct 2 is actively underpinned twice. Underground space development and construction and reconstruction of the uneven deformation and settlement of the viaduct column 1 in permanent use ensure the safety and stability of the viaduct 2 under normal operation. In addition, the newly developed underground space structure was used as the basis of the temporary underpinning system for this underpinning and layer increase, which saved a lot of underpinning pile foundations. Furthermore, with this method of underpinning, the newly developed basement roof can be used as the permanent foundation of the viaduct column 1, which reduces the pile foundation and cap of the viaduct column 1, and at the same time can make the column spacing of the underground space grid larger, and the use of The space is wider.

Preferably, in the above-mentioned viaduct column pier foundation underground reverse layer build-up construction underpinning structure, the step 1 specifically includes:

Step 1-1, constructing an underground space enclosure structure and engineering piles 3 under the elevated, the enclosure structure includes enclosure piles 9 and water-stop curtains 10 arranged outside the enclosure piles 9 .

Step 1-2, excavate the first soil in the underground space to the elevation of the bottom of the elevated pier 13.

Step 1-3, use the engineering pile 3 and the enclosure pile 9 as the support column, construct the basement roof beam 4, the beam slab vacancy at the contact position between the basement roof beam 4 and the viaduct column 1, and reserve the ribs to fill in the vacancy in the later stage. When the basement roof beam 4 is installed, the embedded parts for installing the support column 7 are pre-embedded at the position of the support column 7 on the basement roof beam 4 . The position where the basement roof beam 4 collides with the viaduct column 1 is vacant, so as to facilitate the truncation and reconstruction of the viaduct column 1 .

Step 1-4, set up a temporary underpinning structure on the basement roof beam 4, the lower end of the support column 7 is connected with the embedded parts on the basement roof beam 4, and the support beam 6 is erected on the top of the support column 7, and the support beam 6 and the support column 7 are hinged or fixedly connected, so that the support beam 6 is parallel to the longitudinal direction of the viaduct, and each pair of support beams 6 is arranged on both sides of the viaduct column 1 . In order to improve the bearing capacity of the underpinning temporary structure, not only the embedded parts for installing the support column 7 are pre-embedded when pouring the basement roof beam 4, but also the lower end of the support column 7 is poured in the basement roof beam 4 to further increase The bite force between the support column 7 and the basement roof beam 4 .

Step 1-5, installing a limit device 11 and a hydraulic jack 5 between the viaduct 2 and the support beam 6, the limit device 11 can limit the relative horizontal displacement between the viaduct 2 and the support beam 6, and the limit Bit device 11 is distributed around hydraulic jack 5.

Preferably, the limiting device 11 includes an embedded board 111 and an upper limiting member 112 installed under the embedded board 111, the lower limiting member 113 is fixedly arranged on the support beam 6, and the lower limiting member 113 A groove is formed for the upper limit member 112 to protrude into. The height of the upper limit member 112 is smaller than the depth of the groove, and the embedded plate 111 can rest on the lower limit member 113 . The upper limiter 112 is always located in the groove of the lower limiter 113 , so as to limit the horizontal displacement of the viaduct 2 relative to the support beam 6 .

In this embodiment, in the underpinning structure of the above-mentioned underground reverse layer-adding construction of viaduct pier foundation, the lower limit member 113 includes four right-angled trapezoidal wedge blocks evenly distributed around the hydraulic jack 5, and the upper limit The piece 112 includes four right-angled trapezoidal wedges, and the right-angled waist of the right-angled trapezoidal wedge of the upper limiter 112 is opposite to the right-angled waist of the right-angled trapezoidal wedge of the lower limiter 113 . The right-angled waist of the right-angled trapezoidal wedge of the upper limiter 112 can only move up and down relative to the right-angled trapezoidal wedge of the lower limiter 113, so that the viaduct 2 fixedly connected with the upper limiter 112 cannot be opposite to the lower limiter. 113 The fixedly connected support beam 6 moves horizontally and tilts, so as to ensure the normal operation of the viaduct 2 .

Steps 1-6: After the hydraulic jack 5 pre-jacks the viaduct 2 to underpin the temporary structure and the basement roof beam 4 is deformed and stabilized, the viaduct column 1 is cut statically, and the cutting position is located on the viaduct column 1 lower than the bottom of the support beam 6 .

Steps 1-7, manually chiseling away the reinforcement of the reserved section of the viaduct column 1, so as to facilitate the connection when the viaduct column 1 is rebuilt later, that is, the connection between the repaired section of the viaduct column and the reserved section.

Preferably, in the underpinning structure of the underground reverse layer-adding construction of the viaduct pier foundation, the engineering pile 3 is in the form of a bored cast-in-situ pile inserted into a lattice column.

Preferably, in the underpinning structure of the above-mentioned viaduct column pier foundation underground reverse layer-adding construction, the support column 7 and the viaduct column 1 are arranged staggered along the longitudinal direction of the viaduct.

Preferably, in the underpinning structure of the above-mentioned viaduct column pier foundation underground reverse layer-adding construction, the hydraulic jack 5 is a double-acting jack. When the viaduct 2 moves downward, the extending end of the hydraulic jack 5 stretches to lift the viaduct 2 upward; when the viaduct 2 moves upward, the extending end of the hydraulic jack 5 retracts to pull the viaduct 2 downward .

Preferably, in the above-mentioned viaduct column pier foundation underground reverse layer build-up construction underpinning structure, the step 2 specifically includes:

Step 2-1, excavating the second batch of soil in the basement, removing the elevated pier 13 and the bearing piles used to support the elevated pier 13, and constructing the structural beam slab 12 of the basement first floor.

Step 2-2, continue to excavate the third batch of soil in the basement until the main structure of the underground space is completed, pay close attention to the settlement deformation and stress of the viaduct 2 during the construction of the underground space, and carry out the lifting and shrinkage of the hydraulic jack 5 through the hydraulic jack 5. The adjustment of the deformation stress of the viaduct 2 ensures that the viaduct 2 is in a safe operating state.

In step 2-3, fill in the vacancy of the basement roof girder 4, and reserve the reserved ribs at the position of the viaduct column 1 corresponding to the basement roof girder 4 for later reconstruction of the viaduct column 1.

It can be seen from the above that in step 2, by setting the underpinning temporary structure and the contraction effect of the hydraulic jack 5, it can be ensured that the viaduct is at a predetermined height during the construction process of underground layer addition under the viaduct, ensuring that the viaduct 2 is in a safe operation state.

Preferably, in the underpinning structure of the above-mentioned underground reverse layer-adding construction of viaduct pier foundations, the hydraulic steel pipe support 8 includes steel pipe fixed ends, steel pipe support cylinders, two hydraulic jacks and steel pipe telescopic One end of the two hydraulic jacks is connected to the steel pipe support cylinder, and the other end is connected to the telescopic end of the steel pipe. The telescopic end of the steel pipe is fixedly connected to the basement roof beam 4, and the fixed end of the steel pipe is fixed to the support beam 6. connect. The two hydraulic jacks can provide thrust and pull to the support beam 6 respectively, and the two hydraulic jacks can also provide push and pull to the basement roof beam 4 . The two hydraulic jacks are double-acting jacks.

Preferably, in the above-mentioned viaduct column pier foundation underground reverse layer build-up construction underpinning structure, the step 3 specifically includes:

Step 3-1, set several pairs of hydraulic steel pipe braces 8 between the support beam 6 and the basement roof beam 4, each pair of hydraulic steel pipe braces 8 is located on both sides of the underpinned viaduct column 1, and each pair of hydraulic steel pipe braces 8 and The corresponding viaduct column 1 is arranged along the transverse direction of the viaduct, that is, each pair of hydraulic steel pipe braces 8 and the corresponding viaduct column 1 are located on a horizontal line perpendicular to the longitudinal direction of the viaduct 2, so that each pair of hydraulic steel pipe braces 8 is as close as possible The viaduct column 1 is to make the supporting position of each pair of hydraulic steel pipe braces 8 of the basement roof beam 4 as close as possible to the supporting position of the basement roof beam 4 pair of the reconstructed viaduct column 1 .

Step 3-2: After the installation of the hydraulic steel pipe brace 8 is completed, perform hydraulic pre-jacking to replace the support column, cut the support column, and the viaduct load under operation is directly transmitted to the basement roof beam 4 through the hydraulic steel pipe brace 8 .

Step 3-3, load the hydraulic steel pipe brace 8 to compensate the settlement deformation of the viaduct caused by the deflection deformation after the elevated load acts on the basement roof girder 4, so that the viaduct remains within the safe settlement deformation range. When the hydraulic steel pipe brace is loaded with a constant load, the viaduct After the deformation is stable, steel bars are bound at the viaduct column 1, and concrete is poured on the basement roof beam 4 to rebuild the viaduct column 1.

Step 3-4, after the reconstructed viaduct column 1 reaches the concrete strength, remove the underpinning temporary structure and the hydraulic steel pipe support 8, and complete the construction of the underground layer addition of the viaduct column 1 pier foundation.

In step 3, since several pairs of hydraulic steel pipe braces 8 are set between the support beam 6 and the viaduct 2, every pair of hydraulic steel pipe braces 8 is located on both sides of the viaduct column 1, and every pair of hydraulic steel pipe braces 8 is connected to the corresponding viaduct The column 1 is arranged along the transverse direction of the viaduct, so that each pair of hydraulic steel pipe braces 8 is as close as possible to the viaduct column 1, that is, the supporting position of each pair of hydraulic steel pipe braces 8 for the basement roof beams is as close as possible to the basement roof beams 4 pairs. The supporting position of viaduct column 1 after construction. Therefore, before the reconstruction of the viaduct column 1, the viaduct 2 is underpinned by using the hydraulic steel pipe brace 8 to replace the underpinning temporary structure. Carry out deformation, and then rebuild viaduct column 1. Since the support position of the basement roof beam 4 for each pair of hydraulic steel pipe braces 8 is as close as possible to the support position of the basement roof beam 4 for the reconstructed viaduct column 1, therefore, the viaduct load acts on the rear deflection deformation of the basement roof beam after reconstruction The resulting settlement and deformation of the viaduct is small, thereby effectively reducing the settlement displacement of the viaduct 2 after the construction of the underground layer addition, and ensuring the normal operation of the viaduct 2 .

In summary, the underpinning construction of the underground reverse layer-adding construction of the viaduct pier foundation provided by the utility model uses two active underpinning methods to carry out the underground reverse layer-adding construction of the viaduct pier foundation under operation, and the underground space enclosure structure is constructed first As well as engineering piles and basement roof beams, a temporary underpinning structure is erected on the basement roof beam, and a hydraulic jack is installed on the underpinning temporary structure to actively underpin the elevated bridge. During the construction process, the deformation stress of the viaduct is adjusted through the lifting of the hydraulic jack and the contraction of the oil return to ensure that the viaduct is in a safe operation state during the development of the underground space. After the completion of the construction of the underground space, hydraulic steel pipe braces are erected to underpin the original viaduct to eliminate the settlement and deformation of the viaduct on the roof of the newly developed basement when the permanent viaduct column is rebuilt, and the basement roof beam is used as the permanent foundation of the viaduct column to restore For the original viaduct column, the underpinning construction of the viaduct column pier foundation under operation was completed.

The above description is only a description of the preferred embodiments of the present utility model, and is not any limitation to the scope of the present utility model. Any changes and modifications made by those of ordinary skill in the field of the utility model according to the above disclosures all belong to the protection scope of the claims .

Claims (10)

1. A reverse construction underpinning structure for viaduct pier foundations, characterized in that it comprises: an enclosure structure and engineering piles arranged in the underground space below the viaduct, a basement roof beam arranged on the engineering piles, arranged in the basement The underpinning temporary structure on the roof girder, and the hydraulic jack installed between the underpinning temporary structure and the viaduct for actively underpinning the viaduct, the top protruding end of the hydraulic jack is fixedly connected with the viaduct, the The underpinning temporary structure includes two pairs of supporting beams arranged in parallel and several supporting columns for supporting the supporting beams, the lower ends of the supporting columns are fixedly connected with the basement roof beams, the supporting beams are parallel to the longitudinal direction of the viaduct, Each pair of supporting beams is arranged on both sides of the viaduct column. 2. The underpinning structure of the underground reverse layer-adding construction of viaduct pier foundation as claimed in claim 1, characterized in that, on the basement roof beam, the supporting column position is pre-embedded for installing the embedded parts of the supporting column, and the supporting column The lower end of the basement is connected with the embedded parts on the roof beam of the basement. 3. The underpinning structure of the underground reverse layer-adding construction of the viaduct pier foundation as claimed in claim 1, wherein a spacer is installed corresponding to each hydraulic jack between the viaduct and the supporting beam, and the spacer can The relative horizontal displacement between the elevated bridge and the supporting beam is limited, and the limiting device is distributed around the hydraulic jack. 4. The underpinning structure for underground reverse layer-adding construction of viaduct pier foundations as claimed in claim 3, wherein the limiting device includes a pre-embedded plate and an upper limit member installed under the pre-embedded plate, and the support A lower limit piece is fixed on the beam, and the lower limit piece forms a groove for the upper limit piece to extend into. The height of the upper limit piece is smaller than the depth of the groove, and the embedded plate can rest on the on the lower limit piece. 5. The underpinning structure for underground reverse layer-adding construction of viaduct pier foundations as claimed in claim 4, wherein said lower limiting member comprises four right-angled trapezoidal wedge blocks evenly distributed around said hydraulic jack, said The upper limiter includes four right-angled trapezoidal wedges, and the right-angled waist of the right-angled trapezoidal wedge of the upper limiter is opposite to the right-angled waist of the right-angled trapezoidal wedge of the lower limiter. 6. The underpinning structure for underground reverse layer-adding construction of viaduct pier foundations according to claim 1, characterized in that, the support columns and the viaduct columns are staggered along the longitudinal direction of the viaduct. 7. The underpinning structure for underground reverse layer-adding construction of viaduct pier foundations as claimed in claim 1, wherein the hydraulic jack is a double-acting jack. 8. The underpinning structure for underground reverse layer-adding construction of viaduct pier foundations as claimed in claim 1, wherein several pairs of hydraulic steel pipe braces are arranged between the support beam and the basement roof beam, and each pair of hydraulic steel pipe braces is located on the corresponding viaduct bridge. On both sides of the column, each pair of hydraulic steel pipe braces and the corresponding viaduct column are arranged along the transverse direction of the viaduct. 9. The underpinning structure for underground reverse layer-adding construction of viaduct pier foundations as claimed in claim 8, wherein the hydraulic steel pipe braces include steel pipe fixed ends, steel pipe support cylinders, two sets of Hydraulic jacks and steel pipe telescopic ends, one end of the two hydraulic jacks is connected to the steel pipe support cylinder, the other end is connected to the steel pipe telescopic end, the steel pipe telescopic end is fixedly connected to the basement roof beam, and the steel pipe is fixed The end is fixedly connected to the support beam. 10 . The underpinning structure for underground reverse layer-adding construction of viaduct pier foundations according to claim 1 , wherein the enclosure structure includes enclosure piles and water-stop curtains arranged outside the enclosure piles. 11 .