Construction method of road reconstruction and expansion half-alternate traffic road to bridge structure

Abstract

This invention relates to a construction method for converting a half-width alternating traffic road into a bridge structure in highway reconstruction and expansion, including two construction methods: bridge-before-excavation and excavation-before-bridge. The beneficial effects of this invention are: It employs a lightweight earth embankment with sheet pile protection structure using anchor cables, forming a retaining structure through the sheet piles and providing additional support through anchor cables, effectively ensuring the stability of the foundation pit. During construction, the reverse construction method is used to gradually excavate downwards, reducing the risk of collapse and deformation. Simultaneously, the half-width vertical excavation method reduces the impact on the surrounding environment and traffic, making it suitable for construction scenarios in confined spaces such as underground engineering, tunnels, and subway foundation pits. It has advantages such as high construction flexibility, strong safety, and high efficiency. Before bridge construction, the pre-drilled pile foundation is constructed using a double steel casing combination structure, ensuring the stability and bearing capacity of the roadbed and pile foundation, and reducing the disturbance of the completed structure to subsequent excavation.

Description

Technical Field

[0001] This invention belongs to the field of civil engineering, and in particular relates to a construction method for converting a half-width alternating traffic road into a bridge structure during highway reconstruction and expansion. Background Technology

[0002] The alternating half-width traffic road-to-bridge structure and construction method is a common construction scheme in highway reconstruction and expansion projects. This scheme allows for continuous traffic flow during construction by using alternating half-width traffic, while simultaneously modifying and expanding existing bridges to accommodate increased traffic demand. Currently, this construction method has been applied in several projects with positive results.

[0003] However, current research still has some issues to address. First, traffic safety during construction needs to be prioritized. While alternating half-width traffic can reduce traffic disruption, it also increases potential safety hazards, necessitating strengthened traffic management and safety measures during construction. Second, the impact of construction on traffic needs to be minimized. Since construction inevitably affects traffic, effective measures are needed to reduce this impact, such as rationally scheduling construction time and traffic flow, and proactively managing traffic. Furthermore, construction techniques and processes need continuous improvement and refinement. Currently, the techniques and processes for converting highways into bridges with alternating half-width traffic still have some shortcomings and require further research and improvement to enhance construction efficiency and quality.

[0004] In conclusion, to further promote the development and application of half-width alternating traffic road-to-bridge structures and construction methods in highway reconstruction and expansion, it is necessary to strengthen relevant research and technological breakthroughs, pay attention to traffic safety during construction, reduce the impact of construction on traffic, and continuously improve and refine construction technologies and processes to provide more reliable and economical technical support for highway reconstruction and expansion projects. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a construction method for converting half-width alternating traffic road into a bridge structure in highway reconstruction and expansion.

[0006] This construction method for converting half-width alternating traffic lanes into bridge structures in highway reconstruction and expansion includes two construction methods: bridge first, then excavation, and excavation first, then bridge. The bridge first, then excavation construction includes the following steps:

[0007] Step 1: Half-width excavation. After the steel sheet piles are in place, foamed concrete is filled in layers between the steel sheet piles and the retaining wall behind them to form a steel sheet pile protection structure for the anchored cable reverse lightweight soil embankment.

[0008] Step 2: At the location of the pile hole, divert the existing road surface soil layer into sections for drilling;

[0009] Step three, the crane sets up the outer side casing at the position of the pile hole, and the pile concrete is poured inside the outer side casing;

[0010] Step four, the inner side casing is lowered to the center of the outer side casing, and the pier concrete is poured by using the inner side casing;

[0011] Step five, the abutment is installed on the top of the steel sheet pile, the bridge deck is constructed on the top of the abutment, then the traffic is diverted to the new bridge, and the other half of the new bridge is constructed.

[0012] As preferred, in step one, the traffic is diverted, the soil of the original road surface on one side of the central reservation is excavated, and then the light soil embankment counter-pulling anchor steel sheet supporting structure is constructed at the position of the central reservation for the slope protection of the original road surface.

[0013] As preferred, the light soil embankment counter-pulling anchor steel sheet supporting structure comprises: foam concrete, counter-pulling anchor, steel sheet, anchor device and backing plate; in step one, the steel sheet is installed on both sides of the reserved side soil for fastening treatment, specifically, the hole of the counter-pulling anchor is drilled on the steel sheet first, then the counter-pulling anchor is installed, then the steel sheets on both sides are installed, and then the anchor device is fixed.

[0014] As preferred, in step three, the construction basket below the suspended steel wire rope is lowered to the designated position inside the outer side casing by using the crane, then the pile concrete is poured, and the connecting steel bars are reserved on the top of the pile; the inner side casing is clamped inside the outer side casing, the inner side of the outer side casing is provided with a positioning groove, and the outer side of the inner side casing is provided with a positioning rod; in step four, the positioning rod of the inner side casing is aligned with the positioning groove of the outer side casing at the position of the pile hole by using the crane, then the inner side casing is lowered, the connecting steel bars of the pile are bound with the reinforcement cage of the pier, and then the pier concrete is poured by using the inner side casing.

[0015] As preferred, when the pile and the pier have the same diameter, the integrated construction of the pile and the pier is adopted, and only the pile is poured, that is, step three is directly followed by step five.

[0016] As preferred, in step five, after the construction of the pier and the pile is completed, the abutment and the bridge deck are constructed, then the reserved side soil is excavated, and the light soil embankment counter-pulling anchor steel sheet supporting structure is removed, specifically, the anchor device on one side is loosened first, then the steel sheets are removed respectively, and the other half of the new bridge is constructed.

[0017] As preferred, the abutment is provided with a resting groove; in step five, the bridge deck is placed on the resting groove.

[0018] The road reconstruction and expansion half-alternating traffic road reconstruction bridge structure obtained by any of the above methods.

[0019] The beneficial effects of the present application are:

[0020] 1) The present application adopts anchor cable reverse construction steel sheet pile protection half-vertical excavation technology, adopts anchor cable reverse construction light soil embankment steel sheet pile protection structure, forms a enclosure structure through steel sheet pile, and provides additional support force in combination with anchor cable, effectively guarantees the stability of the foundation pit, reduces the risk of collapse and deformation during construction by using reverse construction method to gradually excavate downward, reduces the influence on the surrounding environment and traffic by adopting half-vertical excavation method, is suitable for construction scenes in limited space such as underground engineering, tunnel, subway foundation pit, and has the advantages of high construction flexibility, high safety, high efficiency and the like.

[0021] 2) The present application adopts the “bridge first and excavation later” technology, innovatively optimizes the sequence of roadbed lead-in pile foundation construction and bridge construction, pre-completes the construction of lead-in pile foundation by using a double-steel casing combination structure before bridge construction, ensures the stability and bearing capacity of the roadbed and pile foundation, reduces the disturbance of subsequent excavation to the completed structure, effectively improves the construction efficiency, reduces the construction risk, and guarantees the engineering quality, especially suitable for engineering environment with complex geological conditions and limited construction site, has significant practicality and popularization value.

[0022] 3) The double-steel casing combination structure involved in the present application is designed ingeniously, can realize rapid and accurate positioning and installation of the steel casing through the cooperation of the positioning rod and the positioning groove, effectively guarantees the perpendicularity and stability thereof; this structure plays an important role in the connection construction between the pile body and the pier column, ensures the efficiency and accuracy of the connection process, reduces the installation error and construction difficulty, and improves the bearing performance and safety of the overall structure, has significant engineering application value and popularization potential.

[0023] 4) The present application adopts the counter-pulling anchor cable support technology, adopts the light soil embankment counter-pulling anchor cable steel sheet support structure, effectively improves the stability and bearing capacity of the support system; the counter-pulling anchor cable is arranged in the light soil embankment, and the anchor cable is connected with the steel sheet to form an overall force structure, thereby effectively dispersing the soil pressure, reducing the burden of the embankment self-weight on the foundation, and improving the anti-slippage and anti-settlement performance of the embankment; the structure is not only convenient to construct and low in material cost, but also can adapt to different geological conditions, has good practicality and economic benefits. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a three-dimensional schematic view of anchor cable reverse construction steel sheet pile protection half-vertical excavation;

[0025] Figure 2 is a vertical schematic view of anchor cable reverse construction steel sheet pile protection half-vertical excavation;

[0026] Figure 3 is a schematic diagram of a cross section of a road reconstruction and expansion half-alternate traffic road reconstruction bridge structure;

[0027] Figure 4 is a three-dimensional schematic diagram of a road reconstruction and expansion half-alternate traffic road reconstruction bridge structure;

[0028] Figure 5 is a schematic diagram of division of excavated soil of a reserved core soil bridgehead cone slope;

[0029] Figure 6 is a three-dimensional schematic diagram of a counter-pulling anchor cable support construction;

[0030] Figure 7 is a three-dimensional schematic diagram of a counter-pulling anchor cable support construction;

[0031] Figure 8 is a three-dimensional schematic diagram of a counter-pulling anchor cable support construction;

[0032] Figure 9 is a three-dimensional schematic diagram of a roadbed lead-hole pile foundation completion;

[0033] Figure 10 is a three-dimensional schematic diagram of a roadbed lead-hole pile foundation;

[0034] Figure 11 is a three-dimensional schematic diagram of a variable-diameter steel casing protection pile connecting column half-section;

[0035] Figure 12 is a three-dimensional schematic diagram of a variable-diameter steel casing protection pile connecting column;

[0036] Figure 13 is a three-dimensional schematic diagram of an outer casing structure;

[0037] Figure 14 is a three-dimensional schematic diagram of an inner casing structure;

[0038] Figure 15 is a three-dimensional schematic diagram of an inner casing structure;

[0039] Figure 16 is a three-dimensional schematic diagram of a variable-diameter steel casing protection pile connecting column half-section;

[0040] Figure 17 is a three-dimensional schematic diagram of a variable-diameter steel casing protection pile connecting column;

[0041] Figure 18 is a three-dimensional schematic diagram of an outer casing structure.

[0042] Explanation of reference signs: 1-pier column, 2-construction basket, 3-bolt, 4-bridge deck slab, 5-anchor rod, 6-suspension steel wire rope, 7-upper soil block, 8-lower soil block, 9-steel sheet pile, 10-resting groove, 11-abutment, 12-pile body, 13-rear soil retaining, 14-foundation bottom plate, 15-foamed concrete, 16-pull anchor cable, 17-steel plate, 18-anchor device, 19-spacer, 20-original pavement soil layer, 21-outer side casing, 22-inner side casing, 23-pile hole, 24-positioning rod, 25-positioning groove, 26-reserved side soil body. DETAILED DESCRIPTION

[0043] The application will be further described below in conjunction with examples. The following examples are only used to help understand the application. It should be pointed out that for ordinary people in the technical field, several modifications can be made without departing from the principles of the application, and these improvements and modifications also fall within the protection scope of the claims of the application.

[0044] Example 1

[0045] As an example, the construction method of the road reconstruction and expansion half-alternate traffic road to bridge structure includes two construction methods of first bridge and then excavation and first excavation and then bridge. The first bridge and then excavation construction includes the following steps:

[0046] Step 1, factory custom support structure and casing parts: anchor rod 5, steel sheet pile 9, pull anchor cable 16, steel plate 17, outer side casing 21, inner side casing 22 are customized in the factory. Specifically, a plurality of rows of inclined anchor rods 5 are arranged on the side of the steel sheet pile 9, a plurality of rows of pull anchor cables 16 are arranged on the side of the steel plate 17, a positioning groove 25 of a positioning rod 24 is arranged on the outer side of the outer side casing 21, and the positioning rods 24 are welded on the outer side of the inner side casing 22 in a radial manner.

[0047] Design of the mixing ratio of foamed concrete 15: According to the water-solid ratio, wet bulk density, water absorption rate, shrinkage rate, fluidity, and fluidity of the foamed concrete 15, the optimal mixing ratio of the foamed concrete 15 is determined, so that the filled foamed concrete 15 has large self-rigidity and low bulk density, reduces the settlement amount of the light embankment behind the abutment, and improves the stability.

[0048] Measurement and lofting: the positions of the steel sheet pile 9, the abutment 11, the steel plate 17, and the pile hole 23 are lofted by using a total station, and the original pavement soil layer 20 is divided into an upper soil block 7 and a lower soil block 8.

[0049] Half-width excavation, after the steel sheet pile 9 is in place, the foam concrete 15 is filled in layers between the steel sheet pile 9 and the rear retaining 13, forming an anchor reverse construction light soil embankment steel sheet pile protection structure; specifically, for the "bridge after excavation" construction, at the position of the central separation belt, first conduct traffic diversion, at the position of the foam concrete 15 filling, first conduct the anchor reverse construction light soil embankment steel sheet pile protection structure construction, specifically, at the steel sheet pile 9 construction position, first construct the foundation bottom plate 14, then use the crane to place the steel sheet pile 9 in place, and install and fix the anchor rod 5; at the position of the foam concrete 15 filling, the mixed foam concrete 15 is filled in layers between the steel sheet pile 9 and the rear retaining 13, and is compacted.

[0050] Step two, at the position of the pile hole 23, the original road surface soil layer 20 is divided into sections and drilled; the drill machine drills the hole of the pier column 1 and the pile body 12 in the original road surface soil layer 20.

[0051] Step three, first weld and lengthen the outer side casing 21, then use the crane to set the outer side casing 21 at the position of the pile hole 23, and conduct the pouring of the pile body 12, specifically, use the crane to lower the construction basket 2 below the suspended steel wire rope 6 to the specified position inside the outer side casing 21, and then conduct the concrete pouring construction of the pile body 12; the crane sets the outer side casing 21 at the position of the pile hole 23, and conducts the concrete pouring construction of the pile body 12 inside the outer side casing 21.

[0052] Step four, lower the inner side casing 22 to the center of the outer side casing 21; use the inner side casing 22 to conduct the concrete pouring construction of the pier column 1.

[0053] After the construction of the pier column 1 and the pile body 12 is completed, according to the partition position of the upper soil block 7 and the lower soil block 8 of the original road surface soil layer 20, according to the idea of "from the outside to the inside, from the top to the bottom", conduct the soil excavation of the original road surface soil layer 20, use the anchor reverse construction steel sheet pile protection structure to conduct half-width vertical excavation, specifically, first excavate the upper soil block 7, and then excavate the lower soil block 8.

[0054] Step five, install the abutment 11 on the top of the steel sheet pile 9, the top of the abutment 11 is provided with a resting groove 10; the bridge deck 4 is constructed in the top resting groove 10 of the abutment 11, then after the traffic diversion to the newly built bridge, the other half of the new bridge is constructed.

[0055] Example two

[0056] As another embodiment, this example two is based on example one and proposes a more specific construction method of a highway reconstruction and expansion half-width alternate traffic road reconstruction bridge structure:

[0057] When using the excavation-then-bridge construction method, in step one, traffic diversion is carried out at the location of the central median. The soil of the original road surface layer 20 on one side of the central median is excavated. Then, a lightweight earth embankment with tie-anchor steel plate support structure is constructed at the location of the central median for slope protection of the original road surface layer 20.

[0058] When using the excavation-then-bridge construction method, in step five, after the pier 1 and pile 12 are completed, the abutment 11 and bridge deck 4 are constructed. Then, the reserved side soil 26 is excavated, and the lightweight earth embankment tie-anchor steel plate support structure is removed. Specifically, the anchor 18 on one side is loosened first, and then the steel plates 17 are removed to carry out the construction of the other half of the new bridge.

[0059] When using the excavation-then-bridge construction method, after the pier 1 and pile 12 are completed, the abutment 11 and bridge deck 4 are constructed. Then, the reserved side soil 26 is excavated, and the lightweight earth embankment tie-anchor steel plate support structure is removed. Specifically, the anchor 18 and pad 19 on one side are loosened first, and then the steel plate 17 is removed respectively. Then, the construction of the other half of the new bridge is carried out.

[0060] It should be noted that the parts in this embodiment that are the same as or similar to those in Embodiment 1 can be referred to each other, and will not be repeated in this application.

[0061] Example 3

[0062] As another embodiment, this second embodiment proposes a more specific construction method for converting a half-width alternating traffic road into a bridge structure based on the first embodiment:

[0063] In step three, a crane is used to lower the construction basket 2 below the suspended steel wire rope 6 to the designated position inside the outer casing 21, and then the concrete pouring of the pile body 12 is carried out. The top of the pile body 12 is reserved with connecting steel bars. The inner casing 22 is fixed inside the outer casing 21. The inner side of the outer casing 21 is provided with a positioning groove 25, and the outer side of the inner casing 22 is provided with a positioning rod 24.

[0064] In step four, the positioning rod 24 of the inner casing 22 is aligned with the positioning groove 25 of the outer casing 21 at the position of the pile hole 23 using a crane. Then the inner casing 22 is lowered, the steel cage of the pier 1 is tied to the connecting steel bars of the pile body 12, and then the concrete pouring construction of the pier 1 is carried out using the inner casing 22.

[0065] When the diameters of pile 12 and pier 1 are inconsistent, the pier 1 and pile 12 are extended. Specifically, the pile 12 is first poured using the outer casing 21, then the connecting steel bars of the pile 12 are reserved, the steel cage of pier 1 is tied to the connecting steel bars of pile 12, and then the concrete of pier 1 is poured using the inner casing 22.

[0066] When the pile body 12 and the pier 1 have the same diameter, the pile-pier integrated construction method is adopted, and only the pile body 12 is poured, that is, after step three, step five is directly implemented.

[0067] It should be noted that the same or similar parts in this embodiment as in embodiments one and two can be mutually referred to and will not be described again in this application.

[0068] Embodiment four

[0069] As another embodiment, this embodiment three is based on embodiments one and two, and proposes a highway reconstruction and expansion half-alternating traffic road-to-bridge structure, which comprises a pier 1, an abutment 11, a pile body 12, an original road surface soil layer 20, a double-steel-casing combined structure, an anchor cable reverse construction light soil embankment steel sheet pile protection structure for vertical excavation protection construction of the original road surface soil layer 20 road-to-bridge half-alternating traffic, and a light soil embankment counter-pulling anchor cable steel sheet support structure for slope protection construction of the original road surface soil layer 20 road-to-bridge.

[0070] As shown in Figures 1 to 4 , the anchor cable reverse construction light soil embankment steel sheet pile protection structure is arranged below the abutment 11, and is used for vertical excavation protection construction of the original road surface soil layer 20 half-alternating traffic road-to-bridge in the “bridge first and road later” construction, which comprises a bolt 3, an anchor rod 5, a steel sheet pile 9, a foundation bottom plate 14, and a foamed concrete 15; the steel sheet pile 9 is obliquely arranged with a plurality of anchor rods 5 on the side surface and is fixed by the bolt 3, the inner side of the bottom of the steel sheet pile 9 is provided with the foundation bottom plate 14, and the foamed concrete 15 is filled between the steel sheet pile 9 and the rear soil retaining 13.

[0071] As shown in Figures 6 to 8 , the light soil embankment counter-pulling anchor cable steel sheet support structure is used for slope protection of the original road surface soil layer 20 road-to-bridge in the “road first and bridge later” construction, which comprises a foamed concrete 15, a counter-pulling anchor cable 16, a steel sheet 17, an anchor device 18, and a backing plate 19; the steel sheets 17 are connected by the counter-pulling anchor cable 16, and the end of the counter-pulling anchor cable 16 is fixed by the anchor device 18 and the backing plate 19; the backing plate 19 is arranged between the steel sheet 17 and the anchor device 18; and the steel sheet 17 is arranged on both sides of the reserved side soil body 26.

[0072] As shown in Figures 9 to 18 , the double-steel-casing combined structure is used for the construction of the pier 1 and the pile body 12, which comprises an outer casing 21, an inner casing 22, a positioning rod 24, and a positioning groove 25; the inner casing 22 is clamped inside the outer casing 21; the inner side of the outer casing 21 is provided with the positioning groove 25; and the outer side of the inner casing 22 is provided with the positioning rod 24.

[0073] As shown in Figure 11As shown, the outer side of the casing 21 is provided with a construction basket 2 for pouring the pier column 1 and the pile body 12, and the positioning rod 24 is placed in the positioning groove 25.

[0074] As shown in Figure 1 and Figure 2 As shown, the anchor rod 5 passes through the reserved hole of the steel sheet pile 9, and is anchored at the outer side of the steel sheet pile 9 by the bolt 3 at the end; the opposite-pulling anchor cable 16 passes through the reserved hole of the steel sheet 17 in sequence, the end of the opposite-pulling anchor cable 16 passes through the backing plate 19, and then is anchored at the outer side of the steel sheet 17 by the anchor 18.

[0075] It should be noted that the same or similar parts in the embodiments 1-3 can be mutually referred to, and will not be described herein again.

[0076] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The same or similar parts between the various embodiments can be mutually referred to.

Claims

1. A construction method for converting a half-width alternating traffic road into a bridge structure during highway reconstruction and expansion, characterized in that, There are two construction methods: bridge first, then excavation, and excavation first, then bridge. The bridge first, then excavation construction includes the following steps: Step 1: Half-width excavation. After the steel sheet piles are in place, foamed concrete is filled in layers between the steel sheet piles and the retaining wall behind them to form a steel sheet pile protection structure for the anchored cable reverse lightweight soil embankment. Step 2: At the location of the pile hole, divert the existing road surface soil layer into sections for drilling; Step 3: The crane installs the outer casing at the location of the pile hole, and the pile concrete is poured inside the outer casing. Step 4: Lower the inner casing to the center of the outer casing; use the inner casing to carry out the concrete pouring of the pier column; Step 5: Install the bridge abutment on top of the steel sheet piles, construct the bridge deck on top of the abutment, then divert traffic to the new bridge and proceed with the construction of the other half of the new bridge. When using the excavation-then-bridge construction method, in step one, traffic diversion is first carried out at the location of the central median. The soil of the original road surface layer on one side of the central median is excavated. Then, a lightweight earth embankment with tie-anchor steel plate support structure is constructed at the location of the central median for slope protection of the original road surface layer. The lightweight earth embankment with tie-anchor steel plate support structure includes: foamed concrete, tie-anchors, steel plates, anchors, and pads. In step one, the steel plates are installed on both sides of the reserved side soil for reinforcement. Specifically, holes for tie-anchors are first drilled in the steel plates, then the tie-anchors are installed, then the steel plates on both sides are installed, and then they are fixed with anchors. When using the excavation-then-bridge construction method, in step five, after the piers and piles are completed, the abutments and bridge decks are constructed. Then, the reserved side soil is excavated, and the lightweight earth embankment tie-anchor steel plate support structure is removed. Specifically, the anchors on one side are loosened first, and then the steel plates are removed separately to carry out the construction of the other half of the new bridge.

2. The construction method for converting a half-width alternating traffic road into a bridge structure in highway reconstruction and expansion according to claim 1, characterized in that, In step three, a crane is used to lower the construction basket under the suspended steel wire rope to the designated position inside the outer casing, and then the pile concrete is poured. The top of the pile is reserved with connecting steel bars. The inner casing is fixed inside the outer casing. The inner side of the outer casing is provided with a positioning groove, and the outer side of the inner casing is provided with a positioning rod. In step four, the crane is used to align the positioning rod of the inner casing with the positioning groove of the outer casing at the position of the pile hole, and then the inner casing is lowered. The steel cage of the pier is tied to the connecting steel bars of the pile, and then the inner casing is used to pour the pier concrete.

3. The construction method for converting a half-width alternating traffic road into a bridge structure in highway reconstruction and expansion according to claim 1, characterized in that, When the diameters of the pile and the pier are the same, the construction method of integrated pile and pier is adopted, and only the pile is poured. That is, after step three is completed, step five is carried out directly.

4. The construction method for converting a half-width alternating traffic road into a bridge structure in highway reconstruction and expansion according to claim 1, characterized in that, The bridge abutment is equipped with a support groove on top; in step five, the bridge deck is placed on the support groove.

5. A highway reconstruction and expansion project involving alternating half-width traffic lanes converted to bridge structures, characterized in that: Obtained by any one of the methods described in claims 1 to 4.

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