Energy-consuming modular unbonded prestressed fabricated road structure and construction method

Abstract

The invention relates to the technical field of roads, in particular to an energy-consuming modular unbonded prestressed assembly road structure and a construction method. Subgrade treatment, surveying and setting-out, and pier column earthwork excavation; hoisting the reinforced concrete pier column, and checking the reserved joint bar; hoisting the L-shaped reinforced concrete curbstone beam, and grouting the connecting sleeve; subgrade reinforcing layer construction and local treatment; adjusting in-place elevation, and grouting anchor slurry; hoisting a four-side reversed rib beam integrated plate; a damping device is installed, joints are processed, and high-pressure grouting is conducted; laying unbonded prestressed tendons; tensioning and anchoring the unbonded prestressed tendons; and fine aggregate concrete is poured, and an asphalt surface layer is paved. The method follows the steps of roadbed strengthening, prefabricating and hoisting, grouting and anchoring connection, sleeve grouting, prestress applying, high-pressure grouting and asphalt surface layer comprehensive paving, is suitable for engineering projects with frequent earthquakes or areas with large long-term vibration effects or with high standard requirements of road design levels, and provides favorable technical support for high-quality development of the field of fabricated roads in China.

Description

Technical Field

[0001] The present invention relates to the technical field of prefabricated roads, and specifically to an energy-consuming modular unbonded prestressed assembled road structure and construction method. Background Art

[0002] To broaden the application field of prefabricated construction technology, the construction of complete sets of key technologies for prefabricated roads has become a new topic in the current industry development. In order to solve the industry pain points in prefabricated roads, such as road alignment problems, large installation errors, many construction processes, difficult installation and adjustment, high construction costs, construction quality, environmental protection and other issues, "an energy-consuming modular unbonded prestressed prefabricated road and its construction method" is proposed. The structure innovation and technical scheme optimization design are carried out by adopting the modular prefabricated post-grouting process. The energy-consuming technology is diversified and integrated to realize the functional design and application of the prefabricated road construction system, which is applicable to engineering projects in areas with frequent earthquakes or large long-term vibration effects or with higher standard requirements for road design levels. It is expected to form a relatively mature new structure, new process, and new method for prefabricated road construction, innovate the structural design, and optimize the construction process. Summary of the Invention

[0003] The purpose of the present invention is to provide an energy-consuming modular unbonded prestressed assembled road structure and construction method to solve the problems raised in the background art.

[0004] To achieve the above purpose, the present invention provides the following technical solution: An energy-consuming modular unbonded prestressed assembled road structure includes a subgrade strengthening layer, reinforced concrete pier columns, L-shaped reinforced concrete curb beams, a four-sided anti-rib beam integrated slab, a grouting layer, prestressed tendons, a fine aggregate concrete layer, damping devices, and an asphalt surface layer; an L-shaped reinforced concrete curb beam is provided above the reinforced concrete pier columns, a subgrade reinforcement layer and a four-sided anti-rib beam integrated slab are provided between adjacent two L-shaped reinforced concrete curb beams, a grouting layer is provided between the subgrade reinforcement layer and the four-sided anti-rib beam integrated slab, a fine aggregate concrete layer is provided on the four-sided anti-rib beam integrated slab, prestressed tendons are provided inside the fine aggregate concrete layer, and an asphalt surface layer is further provided above the overall structure.

[0005] Preferably, the subgrade strengthening layer is arranged above the subgrade soil layer. Reinforced concrete piers are provided inside the subgrade soil layer. Embedded reinforcing bars are provided inside the reinforced concrete piers. The embedded reinforcing bars and the L-shaped reinforced concrete curb beam above them are connected by grouting with a steel sleeve. The thickness of the subgrade strengthening layer is not less than 200 mm. The minimum cross-sectional dimension of the reinforced concrete pier is not less than 800 mm, and the height is 450 mm - 600 mm. The length of the embedded reinforcing bar extending into the reinforced concrete pier is not less than 350 mm, and a 90-degree hook is provided at the bottom. The outer extension length of the embedded reinforcing bar is not less than 2 / 3 of the length of the steel sleeve and not less than 150 mm. The number of embedded reinforcing bars provided in each reinforced concrete pier is not less than 6 to enhance the connection strength between the reinforced concrete pier and the L-shaped reinforced concrete curb beam and improve the seismic performance of the structure.

[0006] Preferably, both ends of the four-sided inverted rib beam integrated slab are supported on the L-shaped reinforced concrete curb beam. Embedded steel inserts are provided at the bottoms of both ends of the four-sided inverted rib beam integrated slab during the forming process in the precast PC factory. Grout anchor holes are provided at the upper ends of the L-shaped reinforced concrete curb beam. The four-sided inverted rib beam integrated slab and the L-shaped reinforced concrete curb beam are connected and fixed by the grout anchor method using the embedded steel inserts. The cutting length of the embedded steel insert is not less than 160 mm, the middle diameter is not less than 30 mm, and the thickened parts at both ends are not less than 40 mm. The embedded steel insert is anchored into the four-sided inverted rib beam integrated slab by not less than 80 mm. The diameter of the grout anchor hole provided at the upper end of the L-shaped reinforced concrete curb beam is 5 mm - 8 mm larger than the diameter of the thickened parts at both ends of the embedded steel insert, and the designed depth of the grout anchor hole is the outer extension length of the embedded steel insert + 15 mm.

[0007] Preferably, two reserved holes, namely a grouting hole and a bleeding hole, are provided inside each four-sided inverted rib beam integrated slab, and are arranged diagonally along the four-sided inverted rib beam integrated slab. Prestressed tendon perforations are provided on the upper part of the inverted rib beam at the end where the four-sided inverted rib beam integrated slab is connected to the L-shaped reinforced concrete curb beam. Prestressed tendon perforations are also left on the L-shaped reinforced concrete curb beam at the corresponding positions during the production in the precast PC factory. The prestressed tendon passes through the holes in the L-shaped reinforced concrete curb beam and the four-sided inverted rib beam integrated slab and then is tensioned and anchored, and the prestressed tendon is anchored outside the L-shaped reinforced concrete curb beam using an anchor. The diameter of the reserved prestressed tendon perforation is 2 mm - 3 mm larger than the outer diameter of the designed prestressed tendon.

[0008] Preferably, the grouting layer provided between the subgrade strengthening layer and the four-sided inverted rib beam integrated slab is made of fine aggregate concrete or low-shrinkage and slightly expanding grouting material, and the thickness of the grouting layer is not less than 30 mm.

[0009] Preferably, the fine aggregate concrete layer is arranged above the integral slab with four-sided inverted rib beams. The strength of the fine aggregate concrete is not less than C35, and it is cast in modules. The top elevation of the cast fine aggregate concrete exceeds the top surface of the superimposed beams at both ends of the integral slab with four-sided inverted rib beams by at least 50 mm.

[0010] Preferably, along the driving direction, a damping device is provided between the joints of adjacent integral slabs with four-sided inverted rib beams. The damping device is used to resist structural vibration, displacement, etc. for energy dissipation, and improve the durability of the assembled road structure after opening to traffic. The damping device is set in groups at intervals of 2 modules or every 10 m or more, and each group has at least 3; the outer surface of the damping device is coated with anti-corrosion + waterproof material and vacuum sealed. In addition to the damping device, the other spaces between the joints of adjacent integral slabs with four-sided inverted rib beams are filled with loose vermiculite and grouted with asphalt glue, combining precast hoisting with damping energy dissipation.

[0011] The present invention also provides: a construction method for an energy-dissipating modular unbonded prestressed assembled road structure, following the design concept of "strengthening the roadbed, precast hoisting, grouting connection with mortar anchor, sleeve grouting, prestress application, high-pressure grouting, and full paving of asphalt surface layer", applicable to engineering projects in earthquake-prone areas or areas with large long-term vibration effects or high-standard road design requirements. Its construction process flow is roadbed treatment, measurement and setting out, excavation of pier column soil --- hoisting of reinforced concrete pier columns, checking of reserved inserted steel bars --- hoisting of L-shaped reinforced concrete curb beams, sleeve grouting --- construction of roadbed reinforcement layer, local treatment --- adjustment of in-place elevation, anchor mortar perfusion --- hoisting of integral slab with four-sided inverted rib beams --- installation of damping device, joint treatment, high-pressure grouting --- laying of unbonded prestressed tendons --- tensioning and anchoring of unbonded prestressed tendons --- pouring of fine aggregate concrete, paving of asphalt surface layer.

[0012] Preferably, the key technical solutions are as follows:

[0013] Step S1: Roadbed treatment, measurement and setting out, excavation of pier column soil:

[0014] First, the roadbed within the construction scope is excavated and treated. According to the construction plan, the road alignment is clearly defined by measurement and setting out, and the top elevation of the roadbed excavation is located by total station, and the roadbed soil layer is further compacted; the positions of the reinforced concrete pier columns are surveyed and set out, and the soil at the positions of the reinforced concrete pier columns is excavated. The excavation depth of the pier column trench soil should be controlled according to the top elevation of the reinforced concrete pier column, and appropriately over-excavated by 100 mm. The excavation width of the pier column trench soil should be 200 mm - 300 mm larger than the cross-sectional dimension of the precast reinforced concrete pier column, leaving a certain working surface or grouting space. The excavation of the pier column trench soil adopts the manual excavation method, and the protection work after the excavation of the pier column trench soil is strengthened, and the construction in the rainy season is avoided;

[0015] Step S2: Hoisting of reinforced concrete pier columns, checking of reserved inserted steel bars

[0016] Before hoisting the reinforced concrete pier column, the bottom elevation of the earthwork excavation in the pier column groove shall be checked. Combining with the actual height of the precast reinforced concrete pier column produced in the PC factory, the bottom excavation elevation of the earthwork excavation in the pier column groove shall be preliminarily determined. During the on-site construction process, the "bottom elevation method with post-grouting" is adopted for the hoisting and positioning of the reinforced concrete pier column, that is, two precast reinforced concrete slab strips are placed on the earthwork excavation surface in the pier column groove. The length of the precast reinforced concrete slab strip is equal to the side length of the reinforced concrete pier column, and the height of the precast reinforced concrete slab strip is 100 mm. When the reinforced concrete pier column is hoisted on-site, the placement position of the precast reinforced concrete slab strip is the hoisting position of the reinforced concrete pier column. Before hoisting the reinforced concrete pier column, the top elevation of the already installed precast reinforced concrete slab strip shall be further checked to ensure that the reinforced concrete pier column is hoisted and positioned in one go on-site, reducing the workload of repeated checking. After the reinforced concrete pier column is hoisted and positioned, grouting in the groove is carried out in two times, that is, first, fine aggregate concrete is used to carry out the first grouting at the bottom of the hoisted and positioned reinforced concrete pier column. Since precast reinforced concrete slab strips are arranged at the bottom of the pier column in the early stage, on the one hand, it helps the hoisting and positioning of the reinforced concrete pier column, and at the same time, it forms a cavity by jacking up the bottom of the positioned reinforced concrete pier column. The first grouting is carried out to 50 mm above the bottom surface of the reinforced concrete pier column. After the strength of the first grouting reaches more than 75% of the designed strength, the second grouting can be carried out. The second grouting is carried out to the top surface of the reinforced concrete pier column, and the vibration and curing work are strengthened. Finally, the inserted steel bars reserved at the top of the reinforced concrete pier column are straightened and corrected, and the process acceptance records are made.

[0017] Step S3: Hoisting of the L-shaped reinforced concrete curb beam and grouting of the connecting sleeve

[0018] After the reinforced concrete pier column is hoisted and positioned and fixed, the L-shaped reinforced concrete curb beam can be hoisted between the hoisted and positioned adjacent two reinforced concrete pier columns according to the construction plan. Before on-site hoisting, the positional relationship of the inserted steel bars reserved at the top of the reinforced concrete pier column is checked again, focusing on checking the positional relationship of the inserted steel bars reserved at each reinforced concrete pier column and the positional relationship between the inserted steel bars reserved after the hoisting and positioning of the adjacent two reinforced concrete pier columns to ensure the subsequent hoisting and positioning processes of the L-shaped reinforced concrete curb beam. After the L-shaped reinforced concrete curb beam is hoisted and positioned, the steel bar sleeves at the bottom of the L-shaped reinforced concrete curb beam are immediately grouted. Low-shrinkage, micro-expansion and high-strength grouting material is used for high-pressure grouting, the supervision of the grouting process is strengthened, and the concealed works acceptance of the sleeve grouting is done well and records are made.

[0019] Step S4: Construction of the subgrade reinforcement layer and local treatment

[0020] After the L-shaped reinforced concrete curb beams are hoisted and in place, the construction of the subgrade reinforcement layer can be carried out in each module between the L-shaped reinforced concrete curb beams; the subgrade reinforcement layer is laid on the subgrade soil layer after being mixed with cement, fly ash slag, construction waste particles, and coarse sand in a ratio of 1:3.5:6.25:2.18, and then subjected to enhanced compaction treatment, and then cured by the "secondary watering and one-time grouting method". The thickness of the subgrade reinforcement layer is 200mm - 300mm; sufficient loose laying thickness should be left for the on-site laying of the subgrade reinforcement layer, and enhanced compaction should be carried out. Local treatment should be carried out on the subgrade reinforcement layer near the ends of the L-shaped reinforced concrete curb beams. In the case of complex geological environments or complex working conditions, additional steel bars can be left at the subgrade reinforcement layer during the prefabrication of the L-shaped reinforced concrete curb beams in the early stage. The additional steel bars left on the body of the L-shaped reinforced concrete curb beam can extend into the subgrade reinforcement layer or into the grouting layer; there should be at least a 6-hour interval between the first watering and the second watering. After the subgrade reinforcement layer is watered and cured for 24 hours, the one-time grouting process is carried out again;

[0021] Step S5: Adjust the in-place elevation and grout the anchor:

[0022] After the construction of the subgrade reinforcement layer is completed, the top elevation of the in-place L-shaped reinforced concrete curb beams is checked and processed to ensure that the top elevation of the L-shaped reinforced concrete curb beams is the in-place bottom elevation of the four-sided inverted rib beam integral slab; after the elevation check is completed, the grout anchor holes on the top of the in-place L-shaped reinforced concrete curb beams are cleaned with a high-pressure air gun, and all the grout anchor holes are cleaned before the subsequent hoisting of the four-sided inverted rib beam integral slab. There should be no debris left in the grout anchor holes to avoid affecting the subsequent process operations; after all the above processes are completed, anchor grout is poured into the grout anchor holes on the top of each L-shaped reinforced concrete curb beam, and the acceptance work for each process is done well;

[0023] Step S6: Hoist the four-sided inverted rib beam integral slab:

[0024] After the grouting anchor holes on the top surface of each L-shaped reinforced concrete curb beam are processed, the hoisting work of the integrated slab with four-sided inverted rib beams can be carried out; before hoisting the integrated slab with four-sided inverted rib beams, the subgrade reinforcement layer and its internal cavity in each construction section shall be cleaned twice, and no sundries shall be left to avoid affecting the construction quality of the subsequent grouting layer; check the positional relationship between the reserved steel inserts at the lower part of the integrated slab with four-sided inverted rib beams and the grouting anchor holes that have been constructed. When the error is large and affects the hoisting and positioning of the integrated slab with four-sided inverted rib beams, the embedded steel inserts can be adjusted appropriately or the anchor grouting holes can be reamed appropriately. After it is correct, the hoisting of the integrated slab with four-sided inverted rib beams in each construction section can be carried out. The on-site hoisting of the integrated slab with four-sided inverted rib beams shall be in place at one time on the basis of accurately checking the positional relationship between the embedded steel inserts and the anchor grouting holes, and shall not be operated repeatedly to avoid affecting the grouting anchor connection quality; during the hoisting process of the integrated slab with four-sided inverted rib beams, the reserved holes on it shall be blocked with foam plug strips, and the plug strips shall not be pulled out throughout the process or sundries shall enter the grouting layer through the reserved holes after the plug strips fall off;

[0025] Step S7: Install the damping device, joint treatment, and high-pressure grouting:

[0026] After the hoisting of the integrated slab with four-sided inverted rib beams is completed, install the damping device at the joint between the adjacent two integrated slabs with four-sided inverted rib beams for energy consumption of the road main structure after traffic to improve the service life of the assembled road structure; first, install the damping device between the adjacent two integrated slabs with four-sided inverted rib beams, then fill the joint with asphalt glue, and at the same time do the anti-corrosion treatment of the damping device; there shall be no hard sundries such as large-diameter stones in the space where the damping device is installed. Before installing the damper, the space shall be cleaned to ensure the effective energy consumption of the damping device; after installing the damping device, use the high-pressure device to carry out high-pressure grouting on the cavity between the subgrade reinforcement layer and the integrated slab with four-sided inverted rib beams. The operation is carried out through the reserved holes arranged diagonally on the integrated slab with four-sided inverted rib beams. The double holes are grouted synchronously and grouted once, and then pressurized to supplement the grout. After the grouting is completed, seal the holes with rubber plugs and pressurize to supplement the grout again to ensure the completeness of the grouting process, improve the construction quality of the grouting layer, strengthen the maintenance, and do a good job in the acceptance and record of the concealed project of the grouting process during the process;

[0027] Step S8: Lay the unbonded prestressed tendons:

[0028] The unbonded prestressed tendons enter the construction site as finished products. During the on-site construction process, according to the construction plan, the cutting work of the unbonded prestressed tendons shall be done in advance, and the position relationship between the rib beams at the ends of the integrated slab with four-sided reverse rib beams and the embedded holes on the L-shaped reinforced concrete curb beams shall be checked. After the grouting layer construction is completed and the curing time is not less than 48 hours, the unbonded prestressed tendons shall be installed on the upper part of the integrated slab with four-sided reverse rib beams. After the unbonded prestressed tendons pass through the rib beams at the ends of the integrated slab with four-sided reverse rib beams and the embedded holes on the L-shaped reinforced concrete curb beams, they can be fixed to the truss bars on the upper part of the integrated slab with four-sided reverse rib beams by trapezoidal steel supports; after installing the unbonded prestressed tendons according to the linear direction of the prestressed tendons, the joints between the integrated slab with four-sided reverse rib beams and the L-shaped reinforced concrete curb beams shall be caulked or grouted, and the construction shall be carried out in a flowing manner to complete the installation work of the unbonded prestressed tendons in each construction section one by one, and the process acceptance shall be done well;

[0029] Step S9: Tensioning and anchoring of unbonded prestressed tendons:

[0030] The construction shall be carried out in a flowing manner and in modules. During the installation process of the unbonded prestressed tendons, to ensure the requirements of tensioning and anchoring of the prestressed tendons, the cutting length of the unbonded prestressed tendons shall be at least 240 mm longer than the designed length of the prestressed tendons to ensure the operation requirements of the subsequent tensioning and anchoring process of the unbonded prestressed tendons; for the unbonded prestressed tendons of multi-lane or more than 10 m, symmetric tensioning shall be adopted, and the 1.05σcom over-tensioning method shall be used. The unbonded prestressed tendons shall be tensioned and anchored at the outer side ends of the L-shaped reinforced concrete curb beams, and the sealing of the anchor fittings of the unbonded prestressed tendons shall be done well. This process does not require duct grouting as in the construction of bonded prestressed tendons;

[0031] Step S10: Pouring of fine aggregate concrete and paving of asphalt surface course:

[0032] After the tensioning and anchoring of the unbonded prestressed tendons are completed, the pouring work of the fine aggregate concrete layer can be carried out immediately; since the pouring volume of the fine aggregate concrete is not large, the fine aggregate concrete layer can be poured centrally after all the unbonded prestressed tendons in multiple construction sections are installed; the strength of the fine aggregate concrete is preferably C35 - C40, and it shall be poured integrally in multiple construction sections; according to the designed elevation of the top surface of the road structure, the pouring thickness of the fine aggregate concrete shall be effectively controlled. Based on the linear direction of the road, the elevation of the top surface of the main structure shall be measured and set in sections. Generally, the elevation of the top surface of the formed fine aggregate concrete is 50 mm - 100 mm higher than the top surface of the superimposed beams at both ends of the integrated slab with four-sided reverse rib beams. Finally, the overall paving of the asphalt surface course shall be carried out, and the construction shall be carried out in a flowing manner to complete all the structural hoisting work.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention adopts a modular prefabricated post-grouting process to carry out structural innovation and optimization of technical solutions, and diversifies and integrates energy-consuming technologies to realize the functional design and application of the prefabricated road construction system. The overall technical solution follows the design concept of "strengthening the roadbed, prefabricating and hoisting, grouting anchor connection, sleeve grouting, prestress application, high-pressure grouting, and full paving of asphalt surface course", and is applicable to engineering projects in areas with frequent earthquakes or large long-term vibration effects or high-standard requirements for road design levels. It strengthens the research and development and application of new technologies, providing favorable technical support for the high-quality development of the prefabricated road field in China. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a schematic cross-sectional view of the road structure of the present invention;

[0035] Figure 2 is a schematic plan view of the road structure of the present invention;

[0036] Figure 3 is a process flow chart of the construction method of the present invention;

[0037] BRIEF DESCRIPTION OF THE DRAWINGS: 1 - Roadbed strengthening layer, 2 - Reinforced concrete pier column, 3 - L-shaped reinforced concrete curb beam, 4 - Integral slab with four-sided inverted rib beams, 5 - Grouting layer, 6 - Prestressing tendon, 7 - Fine aggregate concrete layer, 8 - Damping device, 9 - Asphalt surface course, 10 - Reserved hole, 11 - Steel sleeve, 12 - Embedded inserted steel bar, 13 - Anchor, 14 - Embedded steel plug-in. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] Please refer to Figure 1-2 , an embodiment of a modular energy-dissipating unbonded prestressed assembled road structure is disclosed in the present invention. The road structure is composed of a roadbed strengthening layer 1, a reinforced concrete pier column 2, an L-shaped reinforced concrete curb beam 3, an integral slab with four-sided inverted rib beams 4, a grouting layer 5, a prestressing tendon 6, a fine aggregate concrete layer 7, a damping device 8, and an asphalt surface course 9. An L-shaped reinforced concrete curb beam 3 is provided above the reinforced concrete pier column 2. A roadbed reinforcement layer and an integral slab with four-sided inverted rib beams 4 are provided between adjacent two L-shaped reinforced concrete curb beams 3. A grouting layer 5 is provided between the roadbed reinforcement layer and the integral slab with four-sided inverted rib beams 4. A fine aggregate concrete layer 7 is provided on the integral slab with four-sided inverted rib beams 4. A prestressing tendon 6 is provided inside the fine aggregate concrete layer 7. An asphalt surface course 9 is further provided above the overall structure. Following the design concept of "strengthening the roadbed, prefabricating and hoisting, grouting anchor connection, sleeve grouting, prestress application, high-pressure grouting, and full paving of asphalt surface course", it is applicable to engineering projects in areas with frequent earthquakes or large long-term vibration effects or high-standard requirements for road design levels.

[0039] The described subgrade strengthening layer 1 is arranged above the subgrade soil layer. Reinforced concrete pier columns 2 are provided inside the subgrade soil layer. Embedded insert bars 12 are provided inside the reinforced concrete pier columns 2. The embedded insert bars 12 and the L-shaped reinforced concrete curb beam 3 above them are connected by grouting with a steel sleeve 11. The thickness of the subgrade strengthening layer 1 is not less than 200 mm. The minimum cross-sectional dimension of the reinforced concrete pier column 2 is not less than 800 mm, and the height is 450 mm - 600 mm. The length of the embedded insert bar 12 extending into the reinforced concrete pier column 2 is not less than 350 mm, and a 90-degree hook is provided at the bottom. The outer extension length of the embedded insert bar 12 is not less than 2 / 3 of the length of the steel sleeve 11 and not less than 150 mm. The number of embedded insert bars 12 provided in each reinforced concrete pier column 2 is not less than 6 to strengthen the connection strength between the reinforced concrete pier column 2 and the L-shaped reinforced concrete curb beam 3 and improve the seismic performance of the structure.

[0040] Both ends of the four-sided inverted rib beam integrated slab 4 are supported on the L-shaped reinforced concrete curb beam 3. Embedded steel inserts 14 are provided at the bottoms of both ends of the four-sided inverted rib beam integrated slab 4 during the manufacturing process in the precast PC factory. The upper end of the L-shaped reinforced concrete curb beam 3 is provided with grout anchor holes. The four-sided inverted rib beam integrated slab 4 and the L-shaped reinforced concrete curb beam 3 are connected and fixed by the grout anchor method using the embedded steel inserts 14. The cutting length of the embedded steel insert 14 is not less than 160 mm, the middle diameter is not less than 30 mm, and the thickened parts at both ends are not less than 40 mm. The embedded steel insert 14 is anchored into the four-sided inverted rib beam integrated slab 4 by not less than 80 mm. The diameter of the grout anchor hole provided at the upper end of the L-shaped reinforced concrete curb beam 3 is 5 mm - 8 mm larger than the diameter of the thickened parts at both ends of the embedded steel insert 14, and the designed depth of the grout anchor hole is the outer extension length of the embedded steel insert 14 + 15 mm.

[0041] There are 2 reserved holes 10 provided inside each four-sided inverted rib beam integrated slab 4, namely a grouting hole and a bleeding hole. The layout positions of the grouting hole and the bleeding hole are preferably arranged along the diagonal of the four-sided inverted rib beam integrated slab 4. The shown in the attached drawing is the basic scheme. There are prestressed tendon perforations provided on the upper part of the inverted rib beam at the end where the four-sided inverted rib beam integrated slab 4 is connected to the L-shaped reinforced concrete curb beam 3. Prestressed tendon perforations are also left on the L-shaped reinforced concrete curb beam 3 at the corresponding positions during the manufacturing and production in the precast PC factory. The prestressed tendon 6 passes through the holes in the L-shaped reinforced concrete curb beam 3 and the four-sided inverted rib beam integrated slab 4 and then is tensioned and anchored, and the prestressed tendon 6 is anchored outside the L-shaped reinforced concrete curb beam 3 using an anchor 13. The diameter of the reserved prestressed tendon perforation is 2 mm - 3 mm larger than the outer diameter of the designed prestressed tendon 6.

[0042] The grouting layer 5 provided between the subgrade strengthening layer 1 and the four-sided inverted rib beam integrated slab 4 uses fine aggregate concrete or low-shrinkage and slightly expanding grouting material, and the thickness of the grouting layer 5 is not less than 30 mm.

[0043] The fine aggregate concrete layer 7 is arranged above the integrated slab with four-sided inverted rib beams 4. The strength of the fine aggregate concrete is not lower than C35, and it is cast in modules. The top elevation of the cast fine aggregate concrete exceeds the top surface of the overlapping beams at both ends of the integrated slab with four-sided inverted rib beams 4 by at least 50 mm.

[0044] Along the driving direction, a damping device 8 is provided between the joints of two adjacent integrated slabs with four-sided inverted rib beams 4. The damping device 8 is used to resist structural vibration, displacement, etc. for energy consumption, improving the durability of the assembled road structure after opening to traffic. The damping device 8 can be set in groups at intervals of 2 modules or every 10 m or more, with at least 3 in each group. The outer surface of the damping device 8 is coated with anti-corrosion + waterproof material and vacuum-sealed. Except for the damping device 8, the other spaces between the joints of two adjacent integrated slabs with four-sided inverted rib beams 4 are filled with loose vermiculite and grouted with asphalt glue, combining precast hoisting and damping energy consumption.

[0045] The present invention also discloses a construction method for an energy-dissipating modular unbonded prestressed assembled road structure, following the design concept of "strengthening the roadbed, precast hoisting, grouting connection with mortar anchor, sleeve grouting, prestress application, high-pressure grouting, and full paving of asphalt surface course", applicable to engineering projects in earthquake-prone areas or areas with long-term large vibration effects or high-standard road design requirements. Its construction process flow is roadbed treatment, surveying and setting out, excavation of pier column soil --- hoisting of reinforced concrete pier columns, checking of reserved inserted steel bars --- hoisting of L-shaped reinforced concrete curb beams, grouting of connecting sleeves --- construction of roadbed reinforcement layer, local treatment --- adjustment of in-place elevation, grouting of anchor mortar --- hoisting of integrated slab with four-sided inverted rib beams --- installation of damping device, joint treatment, high-pressure grouting --- laying of unbonded prestressed tendons --- tensioning and anchoring of unbonded prestressed tendons --- pouring of fine aggregate concrete, paving of asphalt surface course.

[0046] The key technical solutions of this construction method are as follows:

[0047] Step S1: Roadbed treatment, surveying and setting out, excavation of pier column soil

[0048] First, the roadbed within the construction scope is excavated and treated. According to the construction plan, surveying and setting out are carried out to clarify the road alignment. The total station is used to locate the top elevation of the roadbed excavation, and the roadbed soil layer is further compacted. The positions of the reinforced concrete pier columns are measured and set out, and the soil at the locations of the reinforced concrete pier columns is excavated. The excavation depth of the pier column trench soil should be controlled according to the top elevation of the reinforced concrete pier column, with appropriate over-excavation of 100 mm. The excavation width of the pier column trench soil should be 200 mm - 300 mm larger than the cross-sectional dimension of the precast reinforced concrete pier column, leaving a certain working surface or grouting space. The manual excavation method is used for the excavation of the pier column trench soil, and the protection work after the excavation of the pier column trench soil is strengthened, and the rainy season construction is avoided.

[0049] Step S2: Hoisting of reinforced concrete pier columns and checking of reserved inserted steel bars

[0050] Before hoisting the reinforced concrete pier columns, the bottom elevation of the excavation of the pier column groove should be checked. Combining with the actual height of the precast reinforced concrete pier columns produced in the PC factory, the bottom excavation elevation of the pier column groove is initially determined. During the on-site construction process, the "method of post-grouting after padding at the bottom" is adopted for the hoisting and positioning of the reinforced concrete pier columns, that is, two precast reinforced concrete slab strips are placed on the excavation surface of the pier column groove. The length of the precast reinforced concrete slab strips is equal to the side length of the reinforced concrete pier columns, and the height of the precast reinforced concrete slab strips is 100 mm. When the reinforced concrete pier columns are hoisted on-site, the placement position of the precast reinforced concrete slab strips is the hoisting position of the reinforced concrete pier columns. Before hoisting the reinforced concrete pier columns, the top elevation of the already placed precast reinforced concrete slab strips should be further checked to ensure that the reinforced concrete pier columns are hoisted and positioned in one go on-site, reducing the workload of repeated checking. After the reinforced concrete pier columns are hoisted and positioned, grouting in the groove is carried out in two times. That is, first, fine aggregate concrete is used to carry out the first grouting at the bottom of the hoisted and positioned reinforced concrete pier columns. Since precast reinforced concrete slab strips are set at the bottom of the pier columns in the early stage, on the one hand, it helps the hoisting and positioning of the reinforced concrete pier columns, and at the same time, it forms a cavity by jacking up the bottom of the positioned reinforced concrete pier columns. The first grouting is carried out to 50 mm above the bottom surface of the reinforced concrete pier columns. After the strength of the first grouting reaches more than 75% of the design strength, the second grouting can be carried out. The second grouting is carried out to the top surface of the reinforced concrete pier columns, and the vibration and curing work are strengthened. Finally, the reserved inserted steel bars at the top of the reinforced concrete pier columns are straightened and corrected, and the process acceptance records are made.

[0051] Step S3: Hoisting of L-shaped reinforced concrete curb beams and grouting of connecting sleeves

[0052] After the reinforced concrete pier columns are hoisted and positioned and fixed, the L-shaped reinforced concrete curb beams can be hoisted between the hoisted and positioned adjacent two reinforced concrete pier columns according to the construction plan. Before on-site hoisting, the positional relationship of the reserved inserted steel bars at the top of the reinforced concrete pier columns is checked again, focusing on checking the positional relationship of the reserved inserted steel bars at each reinforced concrete pier column and the positional relationship between the reserved inserted steel bars after the adjacent two reinforced concrete pier columns are positioned, so as to ensure the subsequent hoisting and positioning processes of the L-shaped reinforced concrete curb beams. After the L-shaped reinforced concrete curb beams are hoisted and positioned, the steel bar sleeves at the bottom of the L-shaped reinforced concrete curb beams are immediately grouted. Low-shrinkage, slightly expanding and high-strength grouting material is used for high-pressure grouting, and the supervision of the grouting process is strengthened. The concealed works acceptance of the sleeve grouting is done and records are made.

[0053] Step S4: Construction of the subgrade reinforcement layer and local treatment

[0054] After the L-shaped reinforced concrete curb beams are hoisted and positioned in place, the construction of the subgrade reinforcement layer can be carried out within each module between the L-shaped reinforced concrete curb beams. The subgrade reinforcement layer is laid on the subgrade soil layer after being mixed with cement, fly ash slag, construction waste particles, and coarse sand in a ratio of 1:3.5:6.25:2.18, and then subjected to enhanced compaction treatment. Then, the "secondary watering and one-time grouting method" is used for solidification treatment. The thickness of the subgrade reinforcement layer is 200mm - 300mm. When laying the subgrade reinforcement layer on-site, sufficient loose laying thickness should be reserved, and enhanced compaction should be carried out. Local treatment should be carried out on the subgrade reinforcement layer near the ends of the L-shaped reinforced concrete curb beams. In complex geological environments or complex working conditions, additional steel bars can be reserved at the subgrade reinforcement layer during the prefabrication production of the L-shaped reinforced concrete curb beams. The additional steel bars left on the L-shaped reinforced concrete curb beam body can extend into the subgrade reinforcement layer or into the grouting layer. There should be at least a 6-hour interval between the first watering and the second watering. After the subgrade reinforcement layer is watered and solidified for 24 hours, the one-time grouting process is carried out again.

[0055] Step S5: Adjust the installation elevation and grout the anchor

[0056] After the construction of the subgrade reinforcement layer is completed, the top elevation of the installed L-shaped reinforced concrete curb beams is checked and processed to ensure that the top elevation of the L-shaped reinforced concrete curb beams is the bottom elevation for the installation of the four-sided inverted rib beam integrated slab. After the elevation check is completed, a high-pressure air gun is used to clean the grout anchor holes on the top of the installed L-shaped reinforced concrete curb beams, and all the grout anchor holes are cleaned before the subsequent hoisting of the four-sided inverted rib beam integrated slab. There should be no debris left in the grout anchor holes to avoid affecting the subsequent process operations. After all the above processes are completed, anchor grout is poured into the grout anchor holes on the top of each L-shaped reinforced concrete curb beam, and the acceptance work for each process is done well.

[0057] Step S6: Hoist the four-sided inverted rib beam integrated slab

[0058] After the grouting holes on the top surface of each L-shaped reinforced concrete curb beam are processed, the hoisting work of the integrated slab with four-sided inverted rib beams can be carried out. Before hoisting the integrated slab with four-sided inverted rib beams, the subgrade reinforcement layer and its internal cavity in each construction section shall be cleaned twice, and no sundries shall be left to avoid affecting the construction quality of the subsequent grouting layer. Check the positional relationship between the reserved steel inserts at the lower part of the integrated slab with four-sided inverted rib beams and the grouting holes that have been constructed. When the error is large and affects the hoisting and positioning of the integrated slab with four-sided inverted rib beams, the embedded steel inserts can be adjusted appropriately or the grouting holes can be reamed appropriately. After it is correct, the hoisting of the integrated slab with four-sided inverted rib beams in each construction section can be carried out. The on-site hoisting of the integrated slab with four-sided inverted rib beams shall be in place at one time on the basis of accurate verification of the positional relationship between the embedded steel inserts and the grouting holes, and repeated operation is not allowed to avoid affecting the grouting anchor connection quality. During the hoisting process of the integrated slab with four-sided inverted rib beams, the reserved holes on it shall be blocked with foam plug strips, and the plug strips shall not be pulled out throughout the process or sundries shall enter the grouting layer through the reserved holes after the plug strips fall off.

[0059] Step S7: Install the damping device, joint treatment, and high-pressure grouting

[0060] After the hoisting of the integrated slab with four-sided inverted rib beams is completed, a damping device is installed at the joint between two adjacent integrated slabs with four-sided inverted rib beams for energy consumption of the main road structure after opening to traffic, so as to improve the service life of the assembled road structure. First, install the damping device between two adjacent integrated slabs with four-sided inverted rib beams, then fill the joint with asphalt glue, and at the same time, do a good job in the anti-corrosion treatment of the damping device. There shall be no hard sundries such as large-diameter stones in the space where the damping device is installed. The space shall be cleaned before installing the damper to ensure the effective energy consumption of the damping device. After installing the damping device, use a high-pressure device to carry out high-pressure grouting on the cavity between the subgrade reinforcement layer and the integrated slab with four-sided inverted rib beams. The operation is carried out through the reserved holes arranged diagonally on the integrated slab with four-sided inverted rib beams. The two holes are grouted synchronously, grouted once, and then pressurized and replenished with grout again. After the grouting is completed, seal the holes with rubber plugs and pressurize and replenish the grout for the second time to ensure the completeness of the grouting process, improve the construction quality of the grouting layer, strengthen the maintenance, and do a good job in the acceptance and record of the concealed works of the grouting process during the process.

[0061] Step S8: Lay the unbonded prestressed tendons

[0062] The unbonded prestressed tendons enter the construction site as finished products. During the on-site construction process, according to the construction plan, the cutting work of the unbonded prestressed tendons should be done in advance, and the position relationship between the rib beams at the ends of the integrated slab with four-sided inverted rib beams and the embedded holes on the L-shaped reinforced concrete curb beams should be checked. After the grouting layer construction is completed and the curing time is not less than 48 hours, the unbonded prestressed tendons should be installed on the upper part of the integrated slab with four-sided inverted rib beams. After the unbonded prestressed tendons pass through the rib beams at the ends of the integrated slab with four-sided inverted rib beams and the embedded holes on the L-shaped reinforced concrete curb beams, they can be fixed to the truss bars on the upper part of the integrated slab with four-sided inverted rib beams by trapezoidal steel supports. After installing the unbonded prestressed tendons according to the linear direction of the prestressed tendons, the joints between the integrated slab with four-sided inverted rib beams and the L-shaped reinforced concrete curb beams should be caulked or grouted. Carry out flow construction, complete the installation work of the unbonded prestressed tendons in each construction section one by one, and do a good job in the process acceptance.

[0063] Step S9: Tensioning and anchoring of unbonded prestressed tendons

[0064] Carry out flow operation and modular operation. During the installation process of the unbonded prestressed tendons, to ensure the requirements of tensioning and anchoring of the prestressed tendons, the cutting length of the unbonded prestressed tendons should be at least 240 mm longer than the designed length of the prestressed tendons to ensure the operation requirements of the subsequent tensioning and anchoring process of the unbonded prestressed tendons. For multi-lane or unbonded prestressed tendons over 10 m, symmetric tensioning is adopted, and the 1.05σcom over-tensioning method is used. The unbonded prestressed tendons are tensioned and anchored at the outer side ends of the L-shaped reinforced concrete curb beams, and the sealing of the anchor fittings of the unbonded prestressed tendons should be done well. This process does not require duct grouting like the construction of bonded prestressed tendons.

[0065] Step S10: Pouring of fine aggregate concrete and paving of asphalt surface course

[0066] After the tensioning and anchoring of the unbonded prestressed tendons are completed, the pouring work of the fine aggregate concrete layer can be carried out immediately. Since the pouring volume of the fine aggregate concrete is not large, the fine aggregate concrete layer can be poured centrally after all the unbonded prestressed tendons in multiple construction sections are installed. The strength of the fine aggregate concrete is preferably C35 - C40, and it is poured integrally in multiple construction sections. According to the designed elevation of the top surface of the road structure, effectively control the pouring thickness of the fine aggregate concrete. Based on the linear direction of the road, measure and set the elevation of the top surface of the main structure in sections. Generally, the elevation of the top surface of the formed fine aggregate concrete is 50 mm - 100 mm higher than the top surface of the superimposed beams at both ends of the integrated slab with four-sided inverted rib beams. Finally, carry out the overall paving of the asphalt surface course, carry out flow construction, and complete all the structural hoisting work.

[0067] In summary, the present invention adopts a modular prefabricated post-grouting construction process to carry out structural innovation and optimization design of technical solutions, and diversifies and integrates energy-consuming technologies to achieve the functional design and application of the prefabricated road construction system. The overall technical solution follows the design concept of "strengthening the roadbed, prefabricating and hoisting, grouting anchor connection, sleeve grouting, prestressing application, high-pressure grouting, and full paving of asphalt surface course", and is applicable to engineering projects in areas with frequent earthquakes or large long-term vibration effects or with high-standard requirements for road design levels. It strengthens the research and development and application of new technologies, providing favorable technical support for the high-quality development of the prefabricated road field in China.

[0068] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An energy-dissipating modular non-bonded prestressed assembled road structure, characterized in that: It includes a roadbed reinforcement layer, reinforced concrete piers, L-shaped reinforced concrete curb beams, an integrated plate of four-sided anti-rib beams, a grouting layer, prestressed tendons, a fine stone concrete layer, a damping device and an asphalt surface layer; an L-shaped reinforced concrete curb beam is arranged above the reinforced concrete piers, a roadbed reinforcement layer and an integrated plate of four-sided anti-rib beams are arranged between two adjacent L-shaped reinforced concrete curb beams, a grouting layer is arranged between the roadbed reinforcement layer and the integrated plate of four-sided anti-rib beams, a fine stone concrete layer is arranged on the integrated plate of four-sided anti-rib beams, prestressed tendons are arranged inside the fine stone concrete layer, and an asphalt surface layer is also arranged above the overall structure.

2. The energy-dissipative modular non-bonded prestressed assembled road structure according to claim 1, characterized in that: The roadbed reinforcement layer is arranged above the roadbed soil layer, and reinforced concrete piers are arranged inside the roadbed soil layer. Embedded dowels are arranged inside the reinforced concrete piers, and the embedded dowels are connected to the L-shaped reinforced concrete curb beam above them by steel sleeve grouting; the thickness of the roadbed reinforcement layer is not less than 200mm, the minimum cross-sectional dimension of the reinforced concrete pier is not less than 800mm, the height is 450mm~600mm, the length of the embedded dowels extending into the reinforced concrete pier is not less than 350mm, a 90-degree hook is arranged at the bottom, the outward extension length of the embedded dowels is not less than 2 / 3 of the length of the steel sleeve and not less than 150mm, and each reinforced concrete pier is provided with not less than 6 embedded dowels to strengthen the connection strength between the reinforced concrete pier and the L-shaped reinforced concrete curb beam and improve the seismic performance of the structure.

3. The energy-dissipative modular non-bonded prestressed assembled road structure according to claim 1, characterized in that: Both ends of the four-sided inverted rib beam integrated plate are supported on the L-shaped reinforced concrete curb beam. Pre-embedded steel plug-ins are set at the bottom of both ends of the four-sided inverted rib beam integrated plate during the manufacturing process of the assembled PC factory. A grout anchor hole is provided at the upper end of the L-shaped reinforced concrete curb beam. The four-sided inverted rib beam integrated plate and the L-shaped reinforced concrete curb beam are connected and fixed by the grout anchor method through the pre-embedded steel plug-in. The cutting length of the pre-embedded steel plug-in is not less than 160mm, the middle diameter is not less than 30mm, the thickened parts at both ends are not less than 40mm, and the pre-embedded steel plug-in is anchored into the four-sided inverted rib beam integrated plate by not less than 80mm. The diameter of the grout anchor hole provided at the upper end of the L-shaped reinforced concrete curb beam is 5mm to 8mm larger than the diameter of the thickened parts at both ends of the embedded steel plug-in. The designed depth of the grout anchor hole is the overhanging length of the embedded steel plug-in + 15mm.

4. The energy-dissipative modular non-bonded prestressed assembled road structure according to claim 1, characterized in that: Each of the four-sided anti-rib beam integrated plates is provided with two reserved holes, which are a grouting hole and a grouting hole, respectively, and are arranged diagonally along the four-sided anti-rib beam integrated plates; the upper part of the anti-rib beam connecting the four-sided anti-rib beam integrated plates to the end of the L-shaped reinforced concrete curb beam is provided with prestressed tendon through holes, and the L-shaped reinforced concrete curb beam at the corresponding position of the prestressed tendon through holes are also reserved when the prestressed tendon is manufactured in the assembled PC factory. The prestressed tendons are tensioned and anchored after passing through the holes on the L-shaped reinforced concrete curb beam and the four-sided anti-rib beam integrated plates, and the prestressed tendons are anchored to the outside of the L-shaped reinforced concrete curb beam using anchors, and the diameter of the reserved prestressed tendon through holes is 2mm to 3mm larger than the designed prestressed tendon outer diameter.

5. The energy-dissipative modular non-bonded prestressed assembled road structure according to claim 1, characterized in that: The grouting layer set between the roadbed reinforcement layer and the four-side anti-rib beam integrated plate is made of fine stone concrete or low shrinkage and micro-expansion grouting material, and the thickness of the grouting layer is not less than 30mm.

6. The energy-dissipative modular non-bonded prestressed assembled road structure according to claim 1, characterized in that: The fine stone concrete layer is arranged above the integrated plate of the four-sided anti-rib beams. The strength of the fine stone concrete is not less than C35. It is cast in modules. The top surface elevation of the fine stone concrete casting exceeds the top surface of the composite beams at both ends of the integrated plate of the four-sided anti-rib beams by at least 50mm.

7. The energy-dissipative modular non-bonded prestressed assembled road structure according to claim 1, characterized in that: Along the driving direction, damping devices are installed between the joints of two adjacent four-sided inverted rib beam integrated plates. The damping devices are used to resist structural vibration, displacement, etc. for energy consumption, so as to improve the durability of the structure after the prefabricated road is opened to traffic. The damping devices are arranged in a group every 2 modules or every 10m or more, with at least 3 in each group. The outer surface of the damping device is coated with anti-corrosion + waterproof material for vacuum sealing. In addition to the damping device, the other spaces between the joints of two adjacent four-sided inverted rib beam integrated plates are filled with loose vermiculite and filled with asphalt glue, combining prefabrication and hoisting with damping energy consumption.

8. A construction method for an energy-consuming modular non-bonded prestressed assembled road structure, characterized in that: It follows the design concept of "strengthening roadbed, prefabrication and hoisting, grout-anchor connection, sleeve grouting, prestressing, high-pressure grouting, and comprehensive paving of asphalt surface layer". It is suitable for areas with frequent earthquakes or long-term vibration or engineering projects with high road design standards. Its construction process is roadbed treatment, measurement and layout, pier excavation---reinforced concrete pier hoisting, reserved dowel verification---L-type reinforced concrete curb beam hoisting, connection sleeve grouting---roadbed reinforcement layer construction, local treatment---in-situ elevation adjustment, anchor grouting---four-side anti-rib beam integrated plate hoisting---damping device installation, joint treatment, high-pressure grouting---unbonded prestressed tendon laying---unbonded prestressed tendon tensioning and anchoring---fine stone concrete pouring, asphalt surface layer paving.

9. The construction method of the energy-dissipative modular non-bonded prestressed assembled road structure according to claim 8, characterized in that: The key technical solutions are as follows: Step S1: Roadbed treatment, surveying and laying out, pier excavation: First, the roadbed within the construction scope is excavated. According to the construction plan, the road line direction is determined by measuring and laying out. The elevation of the top surface of the roadbed excavation is located using a total station, and the roadbed soil layer is further compacted. The position of the reinforced concrete pier is measured and set, and the earthwork at the reinforced concrete pier is excavated. The excavation depth of the pier groove should be based on the elevation of the top surface of the reinforced concrete pier, and an appropriate over-excavation of 100mm is allowed. The excavation width of the pier groove should be 200mm to 300mm larger than the cross-sectional size of the prefabricated reinforced concrete pier, leaving a certain working surface or grouting space. The pier groove earthwork is excavated by manual excavation, and the protection work after the pier groove earthwork excavation is strengthened, and construction is avoided during the rainy season. Step S2: Lifting of reinforced concrete piers and checking of reserved dowel bars Before the reinforced concrete pier is hoisted, the bottom elevation of the earthwork excavation of the pier groove shall be checked, and the bottom elevation of the earthwork excavation of the pier groove shall be preliminarily determined in combination with the actual height of the prefabricated reinforced concrete pier produced in the PC factory; during the on-site construction, the "bottom padding and then grouting method" is adopted to carry out the hoisting of the reinforced concrete pier, that is, first place two reinforced concrete prefabricated slabs on the earthwork excavation surface of the pier groove, the length of the reinforced concrete prefabricated slabs is equal to the side length of the reinforced concrete pier, and the height of the reinforced concrete prefabricated slabs is 100mm. When the reinforced concrete pier is hoisted on-site, the placement position of the reinforced concrete prefabricated slabs is the hoisting position of the reinforced concrete pier; before the hoisting of the reinforced concrete pier, the top elevation of the installed reinforced concrete prefabricated slabs shall be further checked to ensure that the reinforced concrete The reinforced concrete pier column is hoisted and put into place at one time on site, which reduces the workload of repeated verification. After the reinforced concrete pier column is hoisted and put into place, it is grouted in the groove twice, that is, fine stone concrete is used to carry out the first grouting on the bottom of the reinforced concrete pier column after hoisting and putting into place. Since the reinforced concrete prefabricated slabs are set at the bottom of the pier column in the early stage, it is helpful to hoist the reinforced concrete pier column into place, and the bottom of the reinforced concrete pier column after being put into place is also emptied to form a cavity. The first grouting is carried out to 50mm above the bottom surface of the reinforced concrete pier column. After the first grouting strength reaches more than 75% of the design strength, the second grouting can be carried out. The second grouting is carried out to the top surface of the reinforced concrete pier column to strengthen vibration and maintenance work. Finally, the dowel bars reserved at the top of the reinforced concrete pier column are straightened and corrected, and the process acceptance records are kept. Step S3: L-shaped reinforced concrete curb beam hoisting and connecting sleeve grouting: After the reinforced concrete piers are hoisted into place and fixed, the L-shaped reinforced concrete curb beam can be hoisted between the two adjacent reinforced concrete piers according to the construction plan; before on-site hoisting, check the position relationship of the reserved dowel bars at the top of the reinforced concrete pier again, and focus on checking the position relationship of the reserved dowel bars at each reinforced concrete pier and the position relationship between the reserved dowel bars after the two adjacent reinforced concrete piers are in place, so as to ensure the subsequent L-shaped reinforced concrete curb beam hoisting and positioning process; after the L-shaped reinforced concrete curb beam is hoisted into place, the steel sleeve at the bottom of the L-shaped reinforced concrete curb beam is immediately grouting, and low-shrinkage, micro-expansion, high-strength grouting material is used for high-pressure grouting, and the supervision of the grouting process is strengthened, and the sleeve grouting concealed project acceptance is well done and records are kept; Step S4: Construction of roadbed reinforcement layer, local treatment After the L-shaped reinforced concrete curb beam is hoisted in place, the roadbed reinforcement layer can be constructed in each module between the L-shaped reinforced concrete curb beams; the roadbed reinforcement layer is made of cement, fly ash slag, construction waste particles, and coarse sand in a ratio of 1:3.5:6.25:2.18 and laid on the roadbed soil layer, strengthened compaction treatment, and then solidified by "secondary watering and primary slurry laying method". The thickness of the roadbed reinforcement layer is 200mm~300mm; sufficient space should be left for laying the roadbed reinforcement layer on site. The virtual paving thickness is increased, and compaction is strengthened. The roadbed reinforcement layer near the end of the L-shaped reinforced concrete curb beam is locally treated. In complex geological environments or complex working conditions, additional steel bars can be left at the roadbed reinforcement layer during the prefabrication of the L-shaped reinforced concrete curb beam in the early stage. The additional steel bars left in the L-shaped reinforced concrete curb beam body can be extended into the roadbed reinforcement layer or into the grouting layer; there should be at least 6 hours between the first and second watering, and the grouting process should be carried out again after the roadbed reinforcement layer is watered and solidified for 24 hours; Step S5: Adjust the elevation in place and pour the anchor grout: After the construction of the roadbed reinforcement layer is completed, the elevation of the top surface of the L-shaped reinforced concrete curb beam that has been in place is checked to ensure that the elevation of the top surface of the L-shaped reinforced concrete curb beam is the bottom elevation of the four-side anti-rib beam integrated plate in place; after the elevation is checked, the grout anchor holes on the top surface of the L-shaped reinforced concrete curb beam that has been in place are cleaned with a high-pressure air gun, and all the grout anchor holes are cleaned before the subsequent hoisting of the four-side anti-rib beam integrated plate, and no debris is left in the grout anchor holes to avoid affecting the subsequent process operations; after all the above processes are completed, the anchor grout is poured into the grout anchor holes on the top surface of each L-shaped reinforced concrete curb beam, and the acceptance of each process is done well; Step S6: Hoisting of the integrated plate with four-side inverted rib beams: After the grout anchor holes on the top surface of each L-shaped reinforced concrete curb beam are processed, the hoisting work of the four-side anti-rib beam integrated plate can be carried out; before the hoisting of the four-side anti-rib beam integrated plate, the roadbed reinforcement layer and its internal cavity in each construction section should be cleaned twice, and no debris should be left to avoid affecting the quality of subsequent grouting layer construction; check the position relationship between the reserved steel plug-in at the bottom of the four-side anti-rib beam integrated plate and the completed grout anchor holes. If the error is large and affects the hoisting of the four-side anti-rib beam integrated plate, the embedded steel plug-in can be Make appropriate adjustments or expand the anchor holes appropriately. After everything is correct, you can proceed with the hoisting of the four-side inverted rib beam integrated slab in each construction section. The on-site hoisting of the four-side inverted rib beam integrated slab should be done once the relationship between the embedded steel plug-in and the anchor hole is accurately checked. Repeated operations are not allowed to prevent affecting the quality of the slurry-anchor connection. During the hoisting of the four-side inverted rib beam integrated slab, the reserved holes on it should be sealed with foam plugs. The plugs should not be pulled out or debris should not enter the grouting layer through the reserved holes after the plugs fall off. Step S7: Install damping device, joint treatment, high pressure grouting: After the hoisting of the four-sided anti-rib beam integrated plate is completed, the damping device is installed at the joint between the two adjacent modules of the four-sided anti-rib beam integrated plate, which is used for energy consumption of the main structure of the road after opening to traffic, so as to improve the service life of the assembled road structure; first, the damping device is installed between the two adjacent four-sided anti-rib beam integrated plates, and then the seams are filled with asphalt glue, and the anti-corrosion treatment of the damping device is done; there must be no hard debris such as large-diameter stones in the space where the damping device is installed. Before installing the damper, the space needs to be cleaned to ensure the effective energy consumption of the damping device; after the damping device is installed, a high-pressure device is used to perform high-pressure grouting on the cavity between the roadbed reinforcement layer and the four-sided anti-rib beam integrated plate, and the operation is performed through the reserved holes arranged diagonally on the four-sided anti-rib beam integrated plate, and the two holes are grouted synchronously, grouting is performed once, and grouting is pressurized again. After the grouting is completed, the hole is sealed with a rubber plug, and grouting is pressurized for a second time to ensure that the grouting process is complete, the construction quality of the grouting layer is improved, and maintenance is strengthened. During the process, the acceptance and record of the hidden engineering of the grouting process are done well; Step S8: Laying of unbonded prestressed tendons: The unbonded prestressed tendons are brought into the construction site as finished products. During the on-site construction process, the unbonded prestressed tendons are cut in advance according to the construction plan, and the position relationship between the rib beams at the ends of the four-side anti-rib beam integrated plate and the embedded holes on the L-shaped reinforced concrete curb beam is checked. After the grouting layer is completed and the curing time is not less than 48 hours, the unbonded prestressed tendons are installed on the upper part of the four-side anti-rib beam integrated plate. After the unbonded prestressed tendons pass through the rib beams at the ends of the four-side anti-rib beam integrated plate and the embedded holes on the L-shaped reinforced concrete curb beam, they can be fixed to the truss tendons on the upper part of the four-side anti-rib beam integrated plate with a trapezoidal steel bar bracket; after the unbonded prestressed tendons are installed according to the linear direction of the prestressed tendons, the joints between the four-side anti-rib beam integrated plate and the L-shaped reinforced concrete curb beam are filled or grouted, and the unbonded prestressed tendons in each construction section are installed one by one, and the process acceptance is carried out; Step S9: Unbonded prestressed tendon tensioning and anchoring: Flow operation, modular operation. During the installation of unbonded prestressed tendons, in order to ensure the tensioning and anchoring requirements of the prestressed tendons, the cutting length of the unbonded prestressed tendons should be at least 240mm longer than the design length of the prestressed tendons to ensure the subsequent tensioning and anchoring process requirements of the unbonded prestressed tendons. For unbonded prestressed tendons with multiple lanes or more than 10m, symmetrical tensioning and 1.05σcom super tensioning method are adopted. The unbonded prestressed tendons are tensioned and anchored at the outer edge of the L-shaped reinforced concrete curb beam, and the anchoring work of the unbonded prestressed tendon anchor is done well. This process does not require grouting of the channel as in the construction of bonded prestressed tendons. Step S10: pouring fine stone concrete and paving asphalt surface layer: After the unbonded prestressed tendons are tensioned and anchored, the fine stone concrete layer can be poured immediately; since the amount of fine stone concrete poured is not large, the fine stone concrete layer can be poured intensively after all the unbonded prestressed tendons in multiple construction sections are installed; The strength of fine stone concrete should be C35-C40, and it should be cast in one piece in multiple construction sections. The pouring thickness of fine stone concrete should be effectively controlled according to the design elevation of the top surface of the road structure. The elevation of the top surface of the main structure should be measured and set in sections based on the linear direction of the road. Generally, the top surface elevation of the fine stone concrete casting should exceed the top surface of the composite beams at both ends of the integrated slab of the four-sided anti-rib beams by 50mm-100mm. Finally, the asphalt surface layer should be fully paved and constructed in a continuous flow manner to complete the entire structure hoisting work.

Images