Construction method of "machine-to-beam" steel structure bridge

Abstract

The present invention discloses a "machine-to-beam" type steel structure bridge construction method, including ① on-site construction of bridge foundation piles and bridge piers, installation of a bridge erection machine, the support beam of the bridge erection machine is formed by splicing a plurality of box beam segments with the same structure ② hoisting and erecting the steel main beams from the first span to the (N-2) span by the bridge erection machine ③ setting up a temporary support between the bridge piers of the (N-1) span and the N span, dividing the box beam segments obtained by splitting the support beam into two columns and placing them at the corresponding positions of the temporary support according to the bridge design plan, completing the "machine-to-beam" transformation ④ converting the steel main beam components obtained in step three into a "simply supported to continuous" system; if the steel main beam is a steel-concrete composite beam, then installing the bridge deck and casting the longitudinal and transverse wet joints of the bridge deck ⑤ removing the temporary support to complete the entire construction. The present invention uses the box beam segments of the bridge erection machine as bridge steel main beam components, solves the waste of resources in the removal of the bridge erection machine and the subsequent process, and eliminates the impact of abandoned bridge erection machines on the environment.

Description

Technical Field

[0001] The present invention relates to the technical field of prefabricated bridge construction, and in particular to a "machine-to-beam" type steel structure bridge construction method. Background Art

[0002] Prefabricated construction technology is in line with the country's green development concept and is an important direction for the development of my country's building industrialization. Although prefabricated construction technology started late in bridge construction, it has also developed rapidly. In the world-renowned Hong Kong-Zhuhai-Macao Bridge, prefabricated prefabricated beams and slabs have been used on a large scale. In general, the application of prefabricated construction technology in the construction of large-scale cross-river and cross-sea bridges in my country has become relatively mature.

[0003] The bridge erection machine is a large-scale lifting equipment used in the assembly construction of bridges. Using the bridge erection machine to erect the main beam is a common construction method in the construction of assembled bridges. It is applicable to the main beams of segment assembly or whole-hole erection. This construction method has a high degree of assembly and the construction process is relatively convenient and fast. It conforms to the development trend of assembly construction proposed by the country and is widely used in the construction of railway bridges and highway bridges.

[0004] For small and medium span bridges (span < 60m) that use bridge erection machines for segmental assembly, the bridge erection machine structure that meets the force requirements is relatively simple and small in size. Some structural components can use standardized assembly parts, which is convenient for later disassembly and recycling, and the waste of resources is relatively controllable. However, for the super-large bridge erection machine used for the whole-hole erection of large-span steel-concrete composite beams with a span of 60-120m, due to the large size and weight of the single-hole steel main beam, the force structure of the bridge erection machine needs special design to meet the use requirements. Therefore, the size of the bridge erection machine is significantly larger than the general bridge erection machine used for segmental assembly. The main structure of the bridge erection machine is complex, the amount of steel used in the components is large, and the cost is high. Generally, it can only be used in the construction process of specific bridges. Before the main beam construction, the above-mentioned super-large bridge erection machine is assembled on-site at the construction project site and erected on the pier beam. Once the bridge construction is completed, the bridge erection machine is dismantled. The later disassembly and transportation and recycling of the components are time-consuming and laborious, and the recycling rate is not high, so it will cause more serious waste of resources and adverse effects on the environment. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a "machine-to-beam" type steel structure bridge construction method, which can specifically adopt the following technical solutions:

[0006] The "machine-to-beam" type steel structure bridge construction method of the present invention comprises the following steps:

[0007] The first step is to construct the bridge foundation piles and piers on site, and then install the bridge erection machine, the support beam of which is composed of multiple box beam segments with the same structure;

[0008] The second step is to hoist and erect the steel main beams from the first span to the (N-2) span using a bridge erecting machine;

[0009] The third step is to set up temporary supports between the piers of the (N-1)th span and the Nth span, then lower the support height of the bridge erection machine, remove the electromechanical equipment on the bridge erection machine, split the support beam of the bridge erection machine, and divide the box beam segments obtained by splitting the support beam into two rows according to the bridge design plan and place them at the corresponding positions of the temporary supports. The two rows of box beam segments are laterally connected to form the steel main beam components of the bridge, completing the "machine to beam" transformation;

[0010] The fourth step is to first connect the steel main beam components obtained in step 3 longitudinally in the middle of the span, and then connect them longitudinally at the pier top position to complete the system conversion from "simply supported to continuous"; if the steel main beam is a steel-concrete composite beam, then install the bridge deck and cast the longitudinal and transverse wet joints of the bridge deck;

[0011] Step 5: Remove the temporary support and complete all construction.

[0012] In order to improve the stress condition of the bridge erecting machine and increase its load-bearing capacity, the support beam is spliced ​​by double-layer box beam segments stacked up and down, or by multi-layer box beam segments stacked up and down, and adjacent box beam segments are connected by bolts.

[0013] When the steel main beam is a steel-concrete composite beam, the second step includes:

[0014] S2.1, move the bridge erecting machine to the first span of the bridge, hoist the first span steel main beam into place, install the precast concrete bridge deck, pour the longitudinal and transverse wet joint concrete of the first span bridge deck, and move the bridge erecting machine to the second span after the concrete reaches the design strength;

[0015] S2.2, hoist the second span steel main beam into place, longitudinally weld the first and second span steel main beams, and complete the system conversion of the two span steel main beams from "simply supported to continuous";

[0016] S2.3, install the second span bridge deck, cast the longitudinal and transverse wet joints of the second span bridge deck, and finally cast the bridge deck wet joints at the top of the first and second span piers. When the concrete reaches the design strength, the bridge erection machine continues to move forward;

[0017] S2.4, continue construction according to the method described in the previous steps.

[0018] When the steel main beam is a steel box beam, the second step includes:

[0019] S2.1, move the bridge erecting machine to the first span of the bridge, hoist the first span steel main beam into place, and then move the bridge erecting machine to the second span;

[0020] S2.2, hoist the second span steel main beam into place in the whole hole, carry out longitudinal welding of the first and second span steel beams, and complete the system conversion of the two span steel main beams from "simply supported to continuous";

[0021] S2.3, move the bridge-building machine forward and continue construction according to the method described in the previous steps.

[0022] In the third step, the box girder segments are transversely connected through hollow beams and node plates, or through steel bridge decks and diaphragms to form steel main beam components of the bridge.

[0023] The "machine-to-beam" type steel structure bridge construction method provided by the present invention uses a specially designed box girder segment combination structure as the main load-bearing support beam of the bridge-building machine. In the later stage of bridge-building, the box girder segments of the bridge-building machine can be converted into bridge steel main beam components, thereby achieving the purpose of secondary utilization and on-site conversion of the main structure of the bridge-building machine, solving the waste of resources in the dismantling of the bridge-building machine and the subsequent processes, and eliminating the impact of abandoned bridge-building machines on the environment.

[0024] The present invention has the advantages of simplifying the process and reducing the overall engineering cost. Compared with the existing construction method, the advantages are as follows:

[0025] 1) The present invention effectively reduces the overall project cost. The main structure of the bridge erecting machine is changed into a steel main beam, which realizes the secondary utilization of the main structure of the bridge erecting machine, directly reduces the amount of steel main beams used for bridges, and brings significant economic benefits;

[0026] 2) The present invention simplifies the construction process, not only shortening the construction period of disassembly, transportation, and recycling of the bridge erection machine, but also saving the construction costs generated in this process;

[0027] 3) The construction process of the present invention is more green and intensive, reducing the waste of resources caused by the disassembly of the bridge erecting machine and the adverse impact of disassembly waste on the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of the bridge erecting machine in the present invention.

[0029] Figure 2 It is a structural schematic diagram of the bridge-building machine lifting the steel main beam component in Example 1.

[0030] Figure 3a-3k It is a schematic diagram of the construction steps for erecting a bridge in Example 1.

[0031] Figure 4 yes Figure 3k AA section view in.

[0032] Figure 5 yes Figure 3k BB cross-section diagram in.

[0033] Figure 6 It is a structural schematic diagram of the bridge-building machine lifting the steel main beam component in Example 2.

[0034] Figure 7a-7g It is a schematic diagram of the construction steps for erecting a bridge in Example 1.

[0035] Figure 8 yes Figure 7g CC cross-section diagram in .

[0036] Fig. 9 yes Figure 7g DD cross-section diagram in. DETAILED DESCRIPTION

[0037] The "machine-to-beam" type steel structure bridge construction method described in the present invention is suitable for the whole-hole construction of large-span prefabricated and assembled steel structure bridges with a steel beam unit span of 60-120m. The supporting bridge erection machine is specially manufactured according to the design plan of the steel structure bridge.

[0038] Specifically, Figure 1 , 2 As shown in Figures 6 and 7, the above-mentioned bridge erection machine includes two parallel rows of support beams 1, each row of support beams 1 is composed of box beam segments 11 with the same structure, and in order to improve the stress condition, the box beam segments 11 are mostly designed as stacked structures in the vertical direction, including double-layer stacking or multi-layer stacking. The specific structure and size of the box beam segment 11 should be determined according to the design of the steel main beam. For example, when the cross section of the steel main beam is as follows: Figure 4 In the structure shown in FIG. 1 , the box beam segment 11 is formed as follows Figure 5 The rectangular structure shown; when the cross section of the steel main beam is Figure 8 In the structure shown in FIG. 1 , the box beam segment 11 is formed as follows: Fig. 9 The rectangular structure with a flange plate on one side is shown. The adjacent box girder segments 11 are connected together by bolts. After the box girder segments 11 are disassembled, they can be used as steel main beam components of the assembled bridge M, that is, the "machine-to-beam" construction is realized. Therefore, the cross-sectional dimensions of the box girder segments 11 should be determined according to the cross-sectional dimensions of the steel main beam of the assembled bridge M.

[0039] A lifting unit is provided on the top of the above-mentioned support beam 1, including a first track 21 installed longitudinally above each column of support beams 1, and a plurality of movable beams 22 are provided above the first track 21. Both ends of each movable beam 22 are slidably connected to the first track 21, and a pair of electric rope take-up machines 23 are installed in the middle. A lifting hook 24 is installed at the end of the steel cable of the electric rope take-up machine 23 for lifting and transporting the steel main beam of the prefabricated bridge M.

[0040] A walking unit is provided at the bottom of the support beam 1, including a second track 31 longitudinally installed below each column of support beams 1, and a lifting front leg 32, a middle leg 33 and a rear leg 34 are slidably installed on each second track 31. Specifically, the front leg 32, the middle leg 33 and the rear leg 34 are slidably connected to the second track 31 through longitudinal walking wheels driven by a motor, and a movable buckle is installed between each leg and the support beam, wherein a distribution beam 35 is also connected below the middle leg 33.

[0041] The construction steps of the present invention are described in detail below in the form of embodiments in conjunction with the accompanying drawings. The following embodiments are all implemented on the premise of the technical scheme of the present invention, and detailed implementation methods and specific construction processes are given, but the protection scope of the present invention is not limited to the following embodiments.

[0042] Embodiment 1:

[0043] When the construction object is a six-span one-unit steel-concrete composite continuous beam bridge, and the "machine-to-beam" type steel structure bridge construction method of the present invention is used, the specific steps are as follows:

[0044] The first step is to construct the bridge foundation piles and piers on site, and then install Figure 1 , 2 The bridge erecting machine shown.

[0045] Since the cross section of the steel main beam 5 of the steel-concrete composite continuous beam bridge is Figure 4 As shown in FIG. 1 , the box girder segment 11 of the bridge erection machine support beam 1 is composed of a web plate 51, a bottom plate 52, longitudinal and transverse stiffening ribs 53, a hollow cross beam 54, a node plate 55, and a flange 56, wherein the hollow cross beam 54 is welded to the node plate 55. Figure 5 The rectangular structure shown in FIG. 1 is stacked up and down in double layers so as to be transversely connected by a node plate 111 and a plurality of welded hollow beams 112 to form a structure as shown in FIG. Figure 5 The steel main beam member 8 is shown.

[0046] The second step is, Figure 3a-3k As shown, the steel main beams of the first to fourth spans are hoisted and erected by a bridge erecting machine, including:

[0047] S2.1, move the bridge erecting machine to the first span of the bridge, hoist the first span steel main beam into place, install the precast concrete bridge deck, pour the longitudinal and transverse wet joint concrete of the first span bridge deck, and move the bridge erecting machine to the second span after the concrete reaches the design strength;

[0048] Specifically, the front and rear rows of beam transport vehicles 4 transport the first span steel main beam 5 on the main beam, the front row stops near the middle leg 33 of the bridge erecting machine, and the front end of the steel main beam 5 is hoisted by the sliding electric rope take-up machine 23, and the rear end of the steel main beam 5 is still placed on the beam transport vehicle 4 (see Figure 3b), the steel main beam 5 moves forward slowly, and when the rear end of the steel main beam 5 moves to the vicinity of the middle support leg 33, the second electric rope collecting machine 23 lifts the rear end of the steel main beam 5 to hoist the first span of the steel main beam 5 into place (see Figure 3c ); after that, the precast concrete bridge deck 6 is hoisted into place (see Figure 3d ), pour the longitudinal and transverse wet joint concrete of the first span bridge deck, and when the concrete reaches the designed strength, the bridge erection machine moves to the second span (see Figure 3e ).

[0049] S2.2, hoist the second span steel main beam 5 into place throughout the hole, longitudinally weld the first and second span steel main beams 5, and complete the system conversion of the two span steel main beams from "simply supported to continuous";

[0050] S2.3, install the second span concrete bridge deck 6, cast the longitudinal and transverse wet joints of the second span bridge deck, and finally cast the bridge deck wet joints at the top of the first and second span piers, and wait for the concrete to reach the design strength;

[0051] S2.4, the bridge-erecting machine continues to move forward and continues construction according to the method described in the previous steps.

[0052] The third step is to set up a temporary support 7 between the piers of the fifth span and the sixth span, then lower the support height of the bridge erecting machine, remove the electromechanical equipment on the bridge erecting machine, split the support beam 1 of the bridge erecting machine, and divide the box beam segments 11 obtained by splitting the support beam 1 into two rows according to the bridge design plan and place them at the corresponding positions of the temporary support 7, and connect the two rows of box beam segments 11 horizontally to form the steel main beam components 8 of the bridge, thus completing the "machine to beam" transformation;

[0053] Specifically, the upper and lower layers of the bridge erection machine support beam 1 are first separated, and the upper box beam segments 11 are first split according to the segments. According to the stress characteristics of the bridge main beam, different box beam segments 11 are placed on the pier of the last hole and the temporary support 7 and arranged in two rows symmetrically. The two box beam segments 11 in the transverse direction of the bridge are welded and connected by node plates 111 and a plurality of hollow beams 112 to form a Figure 5 The steel main beam member 8 shown in the figure has completed the process of converting the upper layer into a single-span bridge (see Figure 3i ); Then, the lower box girder segment 11 of the bridge erector is disassembled in the same way and placed on the pier of the fifth span and the temporary support 7, completing the process of converting the lower span into a single span; Finally, the remaining parts of the bridge erector are dismantled (see Figure 3j ).

[0054] The fourth step is to first connect the steel main beam member 8 obtained in step 3 longitudinally at the mid-span and then at the pier top to complete the system conversion from "simply supported to continuous"; then install the bridge deck and cast the longitudinal and transverse wet joints of the bridge deck;

[0055] The fifth step is to remove the temporary support 7 and complete the entire construction.

[0056] Embodiment 2:

[0057] When the construction object is a six-span one-unit continuous steel beam bridge, and the "machine-to-beam" type steel structure bridge construction method of the present invention is used, the specific steps are as follows:

[0058] The first step is to construct the bridge foundation piles and piers on site, and then install Figure 1 , 6 The bridge erecting machine shown.

[0059] Since the cross section of the steel main beam 5 of the continuous steel beam bridge is Figure 8 As shown, it is a rectangular box beam with flange plates on both sides. Therefore, the box beam segment 11 constituting the bridge erection machine support beam 1 is as follows Fig. 9 The rectangular structure with flange plates on one side shown in the figure, and its rectangular structure size is smaller than the rectangular structure size of the steel main beam 5, when it constitutes the bridge erection machine support beam 1, it is stacked up and down into a double layer, and the flange plates are arranged oppositely. When the beam is erected, it is horizontally connected through the steel bridge deck 113 and the cross diaphragm 114 to form a structure as shown in the figure. Fig. 9 The steel main beam member 8 is shown.

[0060] The second step is, Figure 7a-7g As shown, the steel main beams of the first to fourth spans are hoisted and erected by a bridge erecting machine, including:

[0061] S2.1, move the bridge erecting machine to the first span of the bridge, hoist the first span steel main beam 5 into place, and then move the bridge erecting machine to the second span (see Figure 7a );

[0062] S2.2, hoist the second span steel main beam 5 into place, carry out longitudinal welding of the first and second span steel beams, and complete the system conversion of the two span steel main beams from "simply supported to continuous" (see Figure 7b , Figure 7c );

[0063] S2.3, move the bridge-building machine forward and continue construction according to the method described in the previous steps.

[0064] The third step is to set up temporary support 7 between the piers of the fifth and sixth spans (see Figure 7d ), then lower the support height of the bridge erecting machine, remove the electromechanical equipment on the bridge erecting machine, split the support beam 1 of the bridge erecting machine, and divide the box beam segments 11 obtained by splitting the support beam 1 into two rows according to the bridge design plan and place them at the corresponding positions of the temporary support 7, and connect the two rows of box beam segments 11 horizontally to form the steel main beam component 8 of the bridge, completing the "machine to beam" transformation (see Figure 7e , Figure 7f ).

[0065] The fourth step is to first connect the steel main beam member 8 obtained in step three longitudinally at the mid-span and then connect it longitudinally at the pier top to complete the system conversion from “simply supported to continuous”.

[0066] Step 5: Remove the temporary support 7 and complete the construction (see Figure 7g ).

[0067] It should be noted that, in the description of the present invention, terms indicating orientation or positional relationships, such as "front", "rear", "left", "right", "vertical", "horizontal", "inside", "outside", etc., are based on the orientation or positional relationships shown in the drawings and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

Claims

1. A "machine-to-beam" type steel structure bridge construction method, characterized in that: The steps include: The first step is to construct the bridge foundation piles and piers on site, and then install the bridge erection machine, the support beam of which is composed of multiple box beam segments with the same structure; The second step is to hoist and erect the steel main beams from the first span to the (N-2) span using a bridge erecting machine; The third step is to set up temporary supports between the piers of the (N-1)th span and the Nth span, then lower the support height of the bridge erection machine, remove the electromechanical equipment on the bridge erection machine, split the support beam of the bridge erection machine, and divide the box beam segments obtained by splitting the support beam into two rows according to the bridge design plan and place them at the corresponding positions of the temporary supports. The two rows of box beam segments are laterally connected to form the steel main beam components of the bridge, completing the "machine to beam" transformation; The fourth step is to first connect the steel main beam components obtained in step 3 longitudinally in the middle of the span, and then connect them longitudinally at the pier top position to complete the system conversion from "simply supported to continuous"; if the steel main beam is a steel-concrete composite beam, then install the bridge deck and cast the longitudinal and transverse wet joints of the bridge deck; Step 5: Remove the temporary support and complete all construction.

2. The "machine-to-beam" type steel structure bridge construction method according to claim 1 is characterized by: The support beam is formed by splicing double-layer box beam segments stacked up and down, or by splicing multi-layer box beam segments stacked up and down, and adjacent box beam segments are connected by bolts.

3. The "machine-to-beam" type steel structure bridge construction method according to claim 1 is characterized by: When the steel main beam is a steel-concrete composite beam, the second step includes: S2.1, move the bridge erecting machine to the first span of the bridge, hoist the first span steel main beam into place, install the precast concrete bridge deck, pour the longitudinal and transverse wet joint concrete of the first span bridge deck, and move the bridge erecting machine to the second span after the concrete reaches the design strength; S2.2, hoist the second span steel main beam into place, longitudinally weld the first and second span steel main beams, and complete the system conversion of the two span steel main beams from "simply supported to continuous"; S2.3, install the second span bridge deck, cast the longitudinal and transverse wet joints of the second span bridge deck, and finally cast the bridge deck wet joints at the top of the first and second span piers. When the concrete reaches the design strength, the bridge erection machine continues to move forward; S2.4, continue construction according to the method described in the previous steps.

4. The "machine-to-beam" type steel structure bridge construction method according to claim 1 is characterized by: When the steel main beam is a steel box beam, the second step includes: S2.1, move the bridge erecting machine to the first span of the bridge, hoist the first span steel main beam into place, and then move the bridge erecting machine to the second span; S2.2, hoist the second span steel main beam into place in the whole hole, carry out longitudinal welding of the first and second span steel beams, and complete the system conversion of the two span steel main beams from "simply supported to continuous"; S2.3, move the bridge-building machine forward and continue construction according to the method described in the previous steps.

5. The "machine-to-beam" type steel structure bridge construction method according to claim 1 is characterized by: In the third step, the box girder segments are transversely connected through hollow beams and node plates, or through steel bridge decks and diaphragms to form steel main beam components of the bridge.

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