Construction method for half-range alternative road-to-bridge structure for reconstruction and extension of road

Abstract

The invention relates to a construction method of a road-to-bridge structure for half-range alternate passage of road reconstruction and expansion. The construction method comprises two construction modes of firstly digging after bridge construction and firstly digging after bridge construction. The light soil embankment steel sheet pile protection structure has the beneficial effects that the anchor cables are adopted for inversely constructing the light soil embankment steel sheet pile protection structure, an enclosure structure is formed through the steel sheet piles, the anchor cables are combined for providing extra supporting force, the stability of a foundation pit is effectively guaranteed, downward excavation is gradually conducted in the construction process through the reverse construction method, and the collapse and deformation risks are reduced; meanwhile, a half-range vertical excavation mode is adopted, influences on the surrounding environment and traffic are reduced, and the method is suitable for construction scenes in limited spaces such as underground engineering, tunnels and subway foundation pits and has the advantages of being high in construction flexibility, high in safety, high in efficiency and the like; before bridge construction, construction of a guide hole pile foundation is completed in advance through a double-steel-casing combined structure, the stability and bearing capacity of a roadbed and the pile foundation are ensured, and disturbance of follow-up excavation to the completed structure is reduced.

Description

Technical Field

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

[0002] The half-width alternating road-bridge structure and construction method for highway reconstruction and expansion is a common construction scheme in highway reconstruction and expansion projects. This scheme uses half-width alternating traffic to allow traffic to continue during the construction period, while the original bridge is renovated and expanded to meet the increase in traffic demand. At present, this construction method has been applied in some projects and has achieved certain results.

[0003] However, there are still some problems to be solved in the current research. First, traffic safety issues during construction need to be taken seriously. Although half-width alternating traffic can reduce the impact on traffic, it also increases traffic safety hazards, and it is necessary to strengthen traffic management and safety measures during construction. Secondly, the impact of construction on traffic needs to be reduced. Since traffic will inevitably be affected to a certain extent during construction, effective measures need to be taken to reduce this impact, such as reasonably arranging construction time and traffic flow, and doing a good job of traffic diversion in advance. In addition, construction technology and process flow need to be continuously improved and perfected. At present, the technology and process of the road-bridge structure and construction method of the half-width alternating traffic reconstruction and expansion of highways still have some shortcomings, which need further research and improvement to improve construction efficiency and quality.

[0004] To sum up, in order to further promote the development and application of half-width alternating traffic road-to-bridge structures and construction methods for highway reconstruction and expansion, it is necessary to strengthen relevant research and technical breakthroughs, pay attention to traffic safety issues during construction, reduce the impact of construction on traffic, and continuously improve and perfect construction technology and process flow to provide more reliable and economical technical support for highway reconstruction and expansion projects. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a construction method for converting a highway into a bridge structure by alternating half-width traffic.

[0006] The construction method of the half-width alternating road-to-bridge structure for highway reconstruction and expansion includes two construction methods: first bridge and then dig; and first dig and then bridge. The first bridge and then dig construction includes the following steps:

[0007] Step 1: Half excavation, after the steel sheet piles are in place, the foam concrete is filled in layers between the steel sheet piles and the rear retaining soil to form an anchor cable reverse lightweight soil embankment steel sheet pile protection structure;

[0008] Step 2: Drill holes in the original road surface soil layer at the location of the pile holes;

[0009] Step 3: The crane sets up an outer casing at the location of the pile hole, and pours the pile concrete inside the outer casing;

[0010] Step 4: Lower the inner casing to the center of the outer casing; use the inner casing to pour the pier concrete;

[0011] Step 5: Install the abutment on top of the steel sheet piles, construct the bridge deck on top of the abutment, and then divert the traffic to the newly built bridge before constructing the other half of the new bridge.

[0012] Preferably, when the dig-before-bridge construction method is used, in step one, traffic diversion is first carried out at the location of the central dividing strip, the soil of the original road surface soil layer on one side of the central dividing strip is dug out, and then a lightweight earth embankment and anchor cable steel plate support structure are constructed at the location of the central dividing strip to protect the slope of the original road surface soil layer.

[0013] Preferably, the lightweight earth embankment tension anchor steel plate support structure comprises: foam concrete, tension anchors, steel plates, anchors and pads; in step one, the steel plates are installed on both sides of the reserved side soil for tensioning and consolidation. Specifically, holes for the tension anchors are first drilled on the steel plates, then the tension anchors are installed, and then the steel plates on both sides are installed, and then fixed with anchors.

[0014] Preferably, in step three, a crane is used to lower the construction hanging basket under the suspended wire rope to a specified position on the inner side of the outer casing, and then the pile concrete pouring construction is carried out, and connecting steel bars are reserved on the top of the pile body; the inner casing is clamped on the inner side of the outer casing, and a positioning groove is provided on the inner side of the outer casing, and a positioning rod is provided on the outer side of the inner casing; in step four, a 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 column is tied to the connecting steel bars of the pile body, and then the inner casing is used to carry out the pier column concrete pouring construction.

[0015] Preferably, when the diameters of the pile body and the pier column are consistent, a pile-column integrated construction method is adopted, and only the pile body is cast, that is, step five is directly implemented after step three is completed.

[0016] Preferably, when the digging-before-bridge construction method is used, in step five, after the piers and piles are constructed, the abutments and bridge decks are constructed, and then the reserved side soil is excavated, and the lightweight earth embankment anchor cable steel plate support structure is removed. Specifically, the anchors on one side are first loosened, and then the steel plates are removed respectively, and the other half of the new bridge is constructed.

[0017] Preferably, a shelf groove is provided on the top of the abutment; in step five, the bridge deck is placed on the shelf groove.

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

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

[0020] 1) The present invention adopts anchor cable reverse steel sheet pile protection half-width vertical excavation technology, adopts anchor cable reverse lightweight earth embankment steel sheet pile protection structure, forms a retaining structure through steel sheet piles, and combines anchor cables to provide additional support force, effectively ensuring the stability of the foundation pit, and uses the reverse method to gradually excavate downward during construction to reduce the risk of landslide and deformation; at the same time, a half-width vertical excavation method is adopted to reduce the impact on the surrounding environment and traffic. It is suitable for construction scenes in limited spaces such as underground projects, tunnels, and subway foundation pits, and has the advantages of high construction flexibility, strong safety, and high efficiency.

[0021] 2) The present invention adopts the "bridge first, dig later" technology, innovatively combines the roadbed guide hole pile foundation construction with the optimized sequence of bridge construction, and uses a double steel casing composite structure to pre-complete the construction of the guide hole pile foundation before bridge construction, thereby ensuring the stability and bearing capacity of the roadbed and pile foundation, reducing the disturbance of subsequent excavation to the completed structure, effectively improving construction efficiency, reducing construction risks, and ensuring project quality. It is particularly suitable for engineering environments with complex geological conditions and limited construction sites, and has significant practicality and promotion value.

[0022] 3) The double steel casing combination structure involved in the present invention is exquisitely designed. By setting the positioning rod and the positioning groove, the steel casing can be quickly and accurately positioned and installed, effectively ensuring its verticality and stability. This structure plays an important role in the connection construction between the pile body and the pier column, ensuring the efficiency and accuracy of the connection process, reducing installation errors and construction difficulties, and at the same time improving the bearing capacity and safety of the overall structure. It has significant engineering application value and promotion potential.

[0023] 4) The present invention adopts the tension anchor cable support technology and the lightweight earth embankment tension anchor cable steel plate support structure, which effectively improves the stability and bearing capacity of the support system; by laying tension anchor cables in the lightweight earth embankment and connecting the anchor cables with the steel plates, an overall force-bearing structure is formed, thereby effectively dispersing the soil pressure, reducing the burden of the embankment's own weight on the foundation, and improving the embankment's anti-slip and anti-subsidence performance; this structure is not only convenient to construct and has low material cost, but also can adapt to different geological conditions, and has good practicality and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a three-dimensional schematic diagram of half vertical excavation protected by steel sheet piles with reverse anchor cables;

[0025] Figure 2 This is a schematic diagram of the vertical elevation of half vertical excavation protected by reverse anchor steel sheet piles;

[0026] Figure 3 It is a cross-sectional diagram of the highway reconstruction and expansion with half-width alternate traffic road converted into a bridge structure;

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

[0028] Figure 5 This is a schematic diagram of the division of the excavated soil for the bridge head cone slope with reserved core soil;

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

[0030] Figure 7 This is a schematic diagram of the vertical view of the anchor cable support construction;

[0031] Figure 8 This is a schematic diagram of the detailed structure of the tension anchor cable support;

[0032] Fig. 9 It is a three-dimensional schematic diagram of the completion of the roadbed lead hole pile foundation;

[0033] Fig.10 It is a three-dimensional schematic diagram of the roadbed lead hole pile foundation;

[0034] Fig.11 It is a three-dimensional schematic diagram of a half-section of a variable diameter steel casing protecting a pile connection column;

[0035] Fig.12 It is a three-dimensional schematic diagram of the variable diameter steel casing protecting the pile connection column;

[0036] Fig.13 It is a three-dimensional schematic diagram of the outer casing structure;

[0037] Fig.14 It is a three-dimensional schematic diagram of the inner casing structure;

[0038] Fig.15 It is a plan view of the inner casing structure;

[0039] Fig.16 It is a schematic diagram of a half-section plane of a variable diameter steel casing protecting a pile connection column;

[0040] Fig.17 It is a schematic diagram of the plan view of the variable diameter steel casing protecting the pile connection column;

[0041] Fig.18 It is a plan view of the outer casing structure.

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

[0043] The present invention is further described below in conjunction with embodiments. The description of the following embodiments is only used to help understand the present invention. It should be noted that for ordinary persons in the art, without departing from the principle of the present invention, the present invention can also be modified in some ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

[0044] Embodiment 1

[0045] As an embodiment, the construction method of the highway reconstruction and expansion half-width alternating road to bridge structure includes two construction methods: bridge first and then dig and dig first and then bridge. The bridge first and then dig construction includes the following steps:

[0046] Step 1. Factory customized support structure and casing parts: Customize anchor rods 5, steel sheet piles 9, tension anchor cables 16, steel plates 17, outer casing 21, and inner casing 22 in the factory. Specifically, multiple rows of inclined anchor rod 5 reserved holes are set on the side of the steel sheet piles 9, multiple rows of tension anchor cable 16 reserved holes are set on the side of the steel plate 17, vertical positioning grooves 25 for positioning rods 24 are set on the outer casing 21, and radial positioning rods 24 are welded on the outer side of the inner casing 22.

[0047] Mix ratio design of foam concrete 15: According to the physical properties of foam concrete 15 such as water-solid ratio, wet bulk density, water absorption rate, shrinkage rate, fluidity, and fluidity, the optimal mix ratio of foam concrete 15 is determined, so that the foam concrete 15 itself has high rigidity and low bulk density, reducing the settlement of the lightweight embankment behind the abutment and improving stability.

[0048] Measurement and layout: Use a total station to layout the positions of the steel sheet piles 9, abutments 11, steel plates 17, and pile holes 23, and divide the original road surface soil layer 20 into two parts: an upper soil block 7 and a lower soil block 8.

[0049] After half-width excavation and the steel sheet piles 9 are in place, the foam concrete 15 is filled in layers between the steel sheet piles 9 and the rear retaining soil 13 to form an anchor cable reverse lightweight earth embankment steel sheet pile protection structure; specifically, for the "bridge first, dig later" construction, at the location of the central dividing strip, traffic diversion is first carried out, and half-width excavation is carried out at the location where the foam concrete 15 is filled, and the anchor cable reverse lightweight earth embankment steel sheet pile protection structure is first constructed. Specifically, at the construction location of the steel sheet piles 9, the foundation slab 14 is first constructed, and then the steel sheet piles 9 are placed in place using a crane, and the anchor rods 5 are installed and fixed; at the location where the foam concrete 15 is filled, the mixed foam concrete 15 is filled in layers between the steel sheet piles 9 and the rear retaining soil 13, and compacted.

[0050] Step 2: Drill holes in the original road surface soil layer 20 in sections at the positions of the pile holes 23; and drill holes for the piers 1 and the pile bodies 12 in the original road surface soil layer 20 using a drilling rig.

[0051] Step three, first weld and lengthen the outer casing 21, then use a crane to drive the outer casing 21 at the position of the pile column hole 23, and cast the pile body 12. Specifically, use a crane to move the construction hanging basket 2 under the hanging wire rope 6 to the specified position on the inside of the outer casing 21, and then carry out concrete pouring construction of the pile body 12; the crane drives the outer casing 21 at the position of the pile column hole 23, and carries out concrete pouring construction of the pile body 12 on the inside of the outer casing 21.

[0052] Step 4: lower the inner casing 22 to the center of the outer casing 21 ; and use the inner casing 22 to perform concrete pouring construction on the pier 1 .

[0053] After the construction of the pier 1 and the pile body 12 is completed, the soil of the original road surface soil layer 20 is excavated according to the zoning positions of the upper soil blocks 7 and the lower soil blocks 8 of the original road surface soil layer 20, according to the idea of ​​"from outside to inside and from top to bottom", and half-width vertical excavation is carried out using the anchor cable reverse steel sheet pile protection structure. Specifically, the upper soil block 7 is excavated first, and then the lower soil block 8 is excavated.

[0054] Step 5, install the abutment 11 on the top of the steel sheet pile 9, and provide a shelf groove 10 on the top of the abutment 11; construct the bridge deck 4 in the shelf groove 10 on the top of the abutment 11, and then divert the traffic to the newly built bridge, and then construct the other half of the new bridge.

[0055] Embodiment 2

[0056] As another embodiment, this embodiment 2 proposes, based on the embodiment 1, a more specific construction method for converting a highway into a half-width alternating road bridge structure:

[0057] When the dig-before-bridge construction method is used, in step one, traffic diversion is first carried out at the location of the central dividing strip, the soil of the original road surface soil layer 20 on one side of the central dividing strip is dug out, and then a lightweight earth embankment and anchor cable steel plate support structure are constructed at the location of the central dividing strip to protect the slope of the original road surface soil layer 20.

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

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

[0060] It should be noted that the parts in this embodiment that are the same or similar to those in the first embodiment can be referenced to each other and will not be described in detail in this application.

[0061] Embodiment 3

[0062] As another embodiment, this embodiment 2 proposes, based on the embodiment 1, a more specific construction method for converting a highway into a half-width alternating road bridge structure:

[0063] In step three, a crane is used to move the construction hanging basket 2 under the suspension wire rope 6 to a specified position on the inner side of the outer casing 21, and then the concrete pouring construction of the pile body 12 is carried out, and connecting steel bars are reserved on the top of the pile body 12; the inner casing 22 is fixed to the inner side of the outer casing 21, and a positioning groove 25 is provided on the inner side of the outer casing 21, and a positioning rod 24 is provided on the outer side of the inner casing 22.

[0064] In step 4, a crane is used to align the positioning rod 24 of the inner casing 22 with the positioning groove 25 of the outer casing 21 at the position of the pile hole 23, and then the inner casing 22 is lowered, the steel cage of the pier 1 and the connecting steel bars of the pile body 12 are tied, and then the inner casing 22 is used to carry out concrete pouring construction of the pier 1.

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

[0066] When the diameters of the pile body 12 and the pier column 1 are the same, a pile-column integrated construction method is adopted, and only the pile body 12 is cast, that is, step five is directly implemented after step three is completed.

[0067] It should be noted that the parts in this embodiment that are the same or similar to those in Embodiments 1 and 2 can be referenced to each other and will not be described in detail in this application.

[0068] Embodiment 4

[0069] As another embodiment, this embodiment three is proposed on the basis of embodiments one and two. This highway reconstruction and expansion half-width alternating traffic road to bridge structure includes: piers 1, abutments 11, piles 12, original road surface soil layer 20, double steel casing combination structure, anchor cable reverse construction lightweight earth embankment steel sheet pile protection structure for half-width vertical excavation protection construction of first building a bridge and then digging the original road surface soil layer 20 to convert the road to the bridge, and lightweight earth embankment double-tension anchor cable steel plate support structure for slope protection construction of first digging the original road surface soil layer 20 and then building the bridge.

[0070] like Figures 1 to 4 As shown, the anchor cable reverse lightweight earth embankment steel sheet pile protection structure is arranged below the abutment 11, and is used for the half-width vertical excavation protection construction of the original road surface soil layer 20 of the "road to bridge" during the "bridge first, dig later" construction, which comprises: bolts 3, anchor rods 5, steel sheet piles 9, foundation slab 14, foam concrete 15; a plurality of anchor rods 5 are obliquely arranged on the side of the steel sheet pile 9 and fixed with bolts 3, a foundation slab 14 is arranged on the inner side of the bottom of the steel sheet pile 9, and foam concrete 15 is filled between the steel sheet pile 9 and the rear retaining wall 13.

[0071] like Figures 6 to 8 As shown, the lightweight earth embankment tension anchor cable steel plate support structure is used for the slope protection of the original road surface soil layer 20 of the "road to bridge" during the "dig first and bridge later" construction, and comprises: foam concrete 15, tension anchor cables 16, steel plates 17, anchors 18, and pads 19; the steel plates 17 are connected by tension anchor cables 16, and are fixed at the ends of the tension anchor cables 16 with anchors 18 and pads 19, pads 19 are provided between the steel plates 17 and the anchors 18, and the steel plates 17 are provided on both sides of the reserved side soil 26.

[0072] like Figures 9 to 18 As shown, the double steel casing combination structure is used for the construction of the pier 1 and the pile body 12, and comprises: an outer casing 21, an inner casing 22, a positioning rod 24, and a positioning groove 25; the inner casing 22 is fixed to the inner side of 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.

[0073] like Fig.11As shown, a construction hanging basket 2 is provided inside the outer casing 21 for pouring the pier 1 and the pile body 12 , and the positioning rod 24 is placed in the positioning groove 25 .

[0074] like 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 to the outer side of the steel sheet pile 9 with a bolt 3 at the end; the tension anchor cable 16 passes through the reserved hole of the steel plate 17 in turn, and the end of the tension anchor cable 16 passes through the pad 19 and is then anchored to the outer side of the steel plate 17 with an anchor 18.

[0075] It should be noted that the parts in this embodiment that are the same or similar to those in Embodiments 1 to 3 can be referenced to each other and will not be described in detail in this application.

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

Claims

1. A construction method for converting a half-width alternately-traveled road into a bridge structure for highway reconstruction and expansion, characterized in that: There are two construction methods: bridge first, dig later and dig first, bridge later. The bridge first, dig later construction includes the following steps: Step 1: Half excavation, after the steel sheet piles are in place, the foam concrete is filled in layers between the steel sheet piles and the rear retaining soil to form an anchor cable reverse lightweight soil embankment steel sheet pile protection structure; Step 2: Drill holes in the original road surface soil layer at the location of the pile holes; Step 3: The crane drives an outer casing at the location of the pile hole, and pours the pile concrete inside the outer casing; Step 4: Lower the inner casing to the center of the outer casing; use the inner casing to pour the pier concrete; Step 5: Install the abutment on top of the steel sheet piles, construct the bridge deck on top of the abutment, and then divert the traffic to the newly built bridge before constructing the other half of the new bridge.

2. The construction method of the highway reconstruction and expansion half-width alternating traffic road-to-bridge structure according to claim 1 is characterized in that: When using the dig-before-bridge construction method, in step one, traffic diversion is first carried out at the location of the central divider, the soil of the original road surface layer on one side of the central divider is excavated, and then a lightweight earth embankment and anchor cable steel plate support structure are constructed at the location of the central divider to protect the slope of the original road surface soil layer.

3. The construction method of the highway reconstruction and expansion half-width alternating traffic road-to-bridge structure according to claim 2 is characterized in that: The lightweight earth embankment tension anchor steel plate support structure comprises: foam concrete, tension anchor cables, steel plates, anchors and pads; in step one, the steel plates are installed on both sides of the reserved side soil for tensioning and consolidation. Specifically, holes for tension anchor cables are first drilled on the steel plates, then the tension anchor cables are installed, and then the steel plates on both sides are installed, and then fixed with anchors.

4. The construction method of the highway reconstruction and expansion half-width alternating road-to-bridge structure according to claim 1 is characterized in that: In step three, a crane is used to lower the construction hanging basket under the suspended wire rope to the designated position on the inner side of the outer casing, and then the pile concrete pouring construction is carried out, and connecting steel bars are reserved on the top of the pile body; the inner casing is clamped on the inner side of the outer casing, and a positioning groove is provided on the inner side of the outer casing, and a positioning rod is provided on the outer side of the inner casing; in step four, a 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 column is tied with the connecting steel bars of the pile body, and then the inner casing is used to carry out the pier column concrete pouring construction.

5. The construction method of the highway reconstruction and expansion half-width alternating traffic road-to-bridge structure according to claim 1 is characterized in that: When the diameters of the pile body and the pier column are the same, an integrated pile-column construction method is adopted, and only the pile body is cast, that is, step five is directly implemented after step three is completed.

6. The construction method of the highway reconstruction and expansion half-width alternating traffic road-to-bridge structure according to claim 3 is characterized in that: When the dig-before-bridge construction method is used, in step five, after the piers and piles are constructed, the abutments and bridge decks are constructed, and then the reserved side soil is excavated, and the lightweight earth embankment anchor cable steel plate support structure is removed. Specifically, the anchors on one side are first loosened, and then the steel plates are removed separately to construct the other half of the new bridge.

7. The construction method of the highway reconstruction and expansion half-width alternating road-to-bridge structure according to claim 1 is characterized in that: A shelf groove is provided on the top of the abutment; in step five, the bridge deck is placed on the shelf groove.

8. Highway reconstruction and expansion with half-width alternating road-to-bridge structure, characterized by: Obtained by the method according to any one of claims 1 to 7.

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