Adjustable elevation modular assembly type road structure and construction method thereof

Abstract

The invention relates to the technical field of road engineering, in particular to an elevation-adjustable modular assembly type road structure and a construction method thereof.The road structure adopts the core technical scheme of prefabrication assembly, pier column supporting, nut pre-leveling, integrated plate efficient in-place and high-pressure grouting, and the construction process includes the steps of roadbed treatment, pier groove excavation and cushion layer pouring. The method comprises the following steps: hoisting a reinforced concrete pier column in place; measuring the elevation and mounting a positioning nut; hoisting a prefabricated bilateral ribbed beam integrated plate in sections and modules; mounting a fixing nut and treating in a mounting groove; the prefabricated curbstone beam is hoisted and fixed; the asphalt surface layer is paved for the second time; and other accessory components are mounted and a project is accepted. The assembly integrated construction technology is adopted, mechanical hoisting is achieved, components are accurately in place, the labor cost is greatly reduced, the construction period is shortened, the environment is protected, the green building standard requirement is met, and good economic benefits and social benefits are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of prefabricated road engineering, and particularly to an adjustable elevation modular prefabricated road structure and a construction method thereof. Background Art

[0002] The prefabricated construction technology has become a key planned construction method. To broaden the application field of the prefabricated construction technology and strengthen structural innovation and technology application, the construction of the complete set of key technologies for prefabricated roads has become a new topic in the current industry development. The high-road constant team of Jiangsu Vocational and Technical College of Engineering has opened up a new direction for the industry development in the "Key Technologies for the Construction of Prefabricated Road Structures" and formed a systematic key technology system. In order to solve the industry pain points in prefabricated roads, such as road alignment problems, large installation errors, many construction processes, difficult installation adjustment, high construction costs, construction quality, environmental protection, etc., our team, on the premise of deeply studying the technologies of relevant scholars, proposed "an adjustable elevation modular prefabricated road structure and a construction method thereof". This technology is the research result of the 2023 Nantong Science and Technology Plan Project undertaken by the high-road constant team of Jiangsu Vocational and Technical College of Engineering: Research and Application of Complete Sets of Key Technologies for the Construction of Prefabricated Roads (PFR Technology System) (Project No.: MSZ2023035). It is hoped that through school-enterprise cooperation, joint efforts will be made to make certain innovative contributions to the safe construction in the field of prefabricated roads in China, innovate the structural design, optimize the construction process, and make certain contributions to the high-quality development of the prefabricated road structure construction field in China. Summary of the Invention

[0003] The purpose of the present invention is to provide an adjustable elevation modular prefabricated road structure and a construction method thereof to solve the problems raised in the background art.

[0004] To achieve the above purpose, the present invention provides the following technical solution: An adjustable elevation modular prefabricated road structure, including reinforced concrete pier columns, high-strength bolt rods, precast double-sided rib beam integrated slabs, precast curb beams, and asphalt surface layers. A cushion layer is provided below the reinforced concrete pier columns, and the high-strength bolt rods and extended pier longitudinal bars are embedded inside, and an anchor plate is provided at the end of the pier longitudinal bars;

[0005] The precast double-sided rib beam integrated slab includes a support beam at the end and an inverted composite slab in the middle. Slurry overflow holes are provided on the composite slab. Truss bars and embedded rivets are also provided at the lower part of the precast double-sided rib beam integrated slab, and the truss bars are arranged in a vertical and horizontal two-way manner;

[0006] Both the supporting beam and the precast curb beam are provided with reserved perforations inside. The high-strength bolt rod passes through the reserved perforations, and fixing nuts are arranged on the high-strength bolt rod. Installation grooves are provided at the tops of the supporting beam and the precast curb beam, and the fixing nuts are accommodated in the installation grooves. The fixing nuts fix the precast double-sided ribbed beam integrated slab and the precast curb beam on the high-strength bolt rod;

[0007] Fine aggregate concrete is poured into the internal cavity of the overall structure by the high-pressure grouting method.

[0008] Preferably, the minimum cross-sectional dimension of the reinforced concrete pier column is not less than 250 mm, and the height is not less than 450 mm; the material of the cushion layer is fine aggregate concrete above C20, the thickness is not less than 60 mm, and the width of the cushion layer exceeds the side of the reinforced concrete pier column by not less than 120 mm on each side; the reinforced concrete pier column and the high-strength bolt rod are integrally prefabricated and formed in the PC factory, and the high-strength bolt rod extends into the reinforced concrete pier column by at least 2 / 3 of the height of the reinforced concrete pier column and not less than 300 mm; the pier longitudinal bars on both sides of the reinforced concrete pier column extend out and are anchored into the cavity of the overall structure, and the anchorage length is not less than 40d and not less than 1000 m, where d is the diameter of the pier longitudinal bar; the number of anchorage plates is set at 100% along with the pier longitudinal bars, and the protective layer thickness of the pier longitudinal bars is not less than 30 mm.

[0009] Preferably, the diameter of the high-strength bolt rod is not less than 30 mm, and the top is flush with the top elevation of the precast curb beam; a positioning nut is arranged on the high-strength bolt rod, and the elevation after the positioning nut is tightened on the high-strength bolt rod is the in-place elevation of the end of the precast double-sided ribbed beam integrated slab.

[0010] Preferably, the cross-sectional dimension of the supporting beam is not less than 200 mm×300 mm, the diameter of the longitudinal stressed reinforcement is not less than 22 mm, the diameter of the stirrups is not less than 8 mm, the spacing is not greater than 150 mm, and the stirrups within 500 mm at each end of the precast double-sided ribbed beam integrated slab should be densely arranged, and the stirrup spacing in the dense area is not greater than 100 mm;

[0011] The thickness of the precast part of the composite slab is not less than 70 mm, and double-layer and double-directional steel bars are arranged inside, and the diameter of the distribution steel bars is not less than 12 mm; the reserved perforations are pre-embedded with steel sleeves, and the steel sleeves are fixed and formed with the concrete pouring of the precast double-sided ribbed beam integrated slab in the PC factory. The diameter of the reserved perforations is 2 mm - 4 mm larger than the diameter of the high-strength bolt rod;

[0012] The installation groove is circular or square, and the minimum dimension is 10 mm - 12 mm larger than the outer diameter of the fixing nut. The internal gap after fixed connection is filled and compacted with asphalt.

[0013] Preferably, the diameter of the truss bars is designed according to the specifications, the spacing of the truss bars does not exceed 800 mm, the embedded rivets are designed with I-shaped steel, the length embedded inside the composite slab is not less than 1 / 2 of the thickness of the precast part of the composite slab and not less than 35 mm, and the length extending into the lower grouting material is not less than 120 mm.

[0014] Preferably, the precast curb beam is prefabricated and formed in the precast PC factory. The internal longitudinal stressed steel bars are arranged not less than 4Φ20. The length of each precast curb beam does not exceed 4.5 m, and the stress requirements during the hoisting process of the precast curb beam are met.

[0015] The present invention also discloses a construction method for an adjustable elevation modular prefabricated road structure, which adopts the core technical scheme of "prefabrication and assembly, pier column support, nut pre-leveling, efficient placement of integrated slab, and high-pressure grouting". The construction process flow is as follows:

[0016] Subgrade treatment, excavation of pier trenches --- Pouring of cushion layer, hoisting and placement of reinforced concrete pier columns --- Measuring elevation, installing positioning nuts --- Hoisting precast double-sided ribbed beam integrated slabs in sections and modules --- Installing and fixing nuts, treating inside the groove --- Installing aluminum formwork and grouting --- Joint treatment, first paving of asphalt surface layer --- Hoisting and fixing of precast curb beams --- Second paving of asphalt surface layer --- Installation of other accessory components and project acceptance.

[0017] Preferably, the key technical scheme is as follows:

[0018] Step S1: Subgrade treatment, excavation of pier trenches:

[0019] First, conduct measurement and layout to determine the road alignment and the elevation of subgrade excavation. The subgrade is reinforced by the resource recycling and utilization of mixed materials such as fly ash slag, slag, and solid particles of construction waste. According to the drawings and technical solutions, strictly control the top elevation after subgrade reinforcement treatment, including indicators such as the elevation of positioning nuts, the top elevation of precast double-sided ribbed beam integrated plates, the top elevation of precast curb beams, and the pouring volume of fine aggregate concrete in the high-pressure grouting layer in subsequent processes. On-site, reinforced concrete piers are used as the supporting components of the overall road structure. After measuring and laying out the plane positions of each pier, the excavation work of the holes for each reinforced concrete pier can be carried out. The reinforced concrete piers can be formed by precast or cast-in-place methods. In complex geological conditions such as sandy soil, silty soil, and abundant groundwater, the cast-in-place method can be selected. The hollow steel pipe pile is used for hole expansion, and concrete is poured inside, that is, the soil is squeezed to form a hole, the steel reinforcement cage is hoisted and placed, the concrete is poured, and the pile is pulled out for turnover to carry out the on-site construction of reinforced concrete piers. This plan does not require a cushion layer. Since the height of the precast reinforced concrete pier does not reach 2m, in a relatively hard geological environment, the manual excavation method can be selected for pier trench excavation. The size of the excavated pier trench should meet the design requirements and leave enough working space. Immediately pour cushion concrete after pier trench excavation, minimize the exposure time of the pier trench, and do a good job in the acceptance and record of the process procedures.

[0020] Step S2: Pour the cushion layer and hoist the reinforced concrete pier into place:

[0021] After the pier trench excavation is completed, the cushion concrete can be poured according to the technical solution. To save the construction period, the reinforced concrete piers should preferably be precast PC components. During on-site construction, directly hoist each precast reinforced concrete pier into place by machine, and do a good job in protecting the high-strength bolt rods inside the reinforced concrete piers and the longitudinal bars at the top of the piers. Problems such as damage to precast components, excessive deformation of high-strength bolt rods or longitudinal bars of the piers, and loss of the anchorage plates at the ends of the longitudinal bars of the piers shall not occur. The extended longitudinal bars on the top surface of the reinforced concrete piers should meet a certain anchorage length according to the drawing requirements, and the steel bars anchored into the installation structure cavity should not be less than 80% of the number of longitudinal bars of the reinforced concrete piers. Before hoisting the reinforced concrete piers, first review the top elevation of the cushion layer to ensure that the error is controllable. During the hoisting process, use the method of drawing positioning lines and control lines for plane positioning, and use a level or total station to review the elevation of the reinforced concrete piers in place. According to the road alignment, use a theodolite to control the plane positions of each reinforced concrete pier after hoisting in sections.

[0022] Step S3: Measure the elevation and install the positioning nuts:

[0023] After the reinforced concrete pier column is hoisted and positioned, check and adjust the deformation of the high-strength bolt rods on the reinforced concrete pier column. Use a level or total station to measure the elevation of the positioning nuts, and mark the elevation of the top surface of the positioning nuts on each high-strength bolt rod. The position relationship of the high-strength bolt rods, the elevation measurement of the positioning nuts, fixed nuts, etc. in adjacent construction sections can be operated synchronously. According to the road alignment, focus on measuring the elevation of the positioning nuts when they are in place. It should be emphasized that the elevation of the top surface of the positioning nuts on the reinforced concrete pier column is the elevation of the on-site hoisting and positioning of the precast double-sided ribbed beam integrated slab in the subsequent process. The elevation error of the top surface of the positioning nuts on each reinforced concrete pier column does not exceed 2 mm. After the on-site elevation measurement, mark it with red paint. It is best that the elevation measurement marks face the outside of the road to facilitate the installation of the positioning nuts one by one on-site. All elevation measurement marks should be in the same direction and not be marked randomly to avoid affecting the operation of on-site technicians. After all the elevation measurement marks of the top surface of the positioning nuts in the construction section are completed, the installation of the positioning nuts can be carried out. The operator should tighten the positioning nuts on-site so that the red mark is faintly visible on its top surface. Regardless of the design of several lanes, the elevation of the top surface of the positioning nuts on all the reinforced concrete pier columns in the transverse direction of the road should be the same. Install accurately on-site according to the construction drawings and technical solutions, and assign special personnel to stand by to do a good job in process acceptance and record keeping;

[0024] Step S4: Hoist the precast double-sided ribbed beam integrated slab in sections and modules:

[0025] After all the elevations of the top surfaces of the positioning nuts on each reinforced concrete pier column are marked and the process acceptance work is done, and after cleaning each reserved hole, the precast double-sided ribbed beam integrated slab can be hoisted in sections and modules. When designing for multiple lanes, it is possible to carry out a flow construction from the middle precast double-sided ribbed beam integrated slab to the ends, hoist the precast double-sided ribbed beam integrated slab one by one, and concentrate all the errors due to design, construction, measurement, etc. at the ends for unified treatment, without affecting the implementation of the overall hoisting plan. During the hoisting of the precast double-sided ribbed beam integrated slab, it is necessary to do a good job in protecting its lower truss bars and embedded bolts. It is not allowed to cause excessive deformation of its lower truss bars and embedded bolts during stacking, hoisting, and positioning processes, which may affect the subsequent construction quality. In the early stage, the lower part of the precast double-sided ribbed beam integrated slab is appropriately suspended along the roadside by adding wooden crossbeams. Add wooden crossbeams at the lower part of the support beams at both ends of the precast double-sided ribbed beam integrated slab. Set the walking route of the mechanical equipment and the stacking area of the precast double-sided ribbed beam integrated slab during on-site hoisting, and use the two-point common arc method to hoist it into place at one time to save the construction period. The hoisting machinery is not allowed to walk under load and strictly execute the hoisting task according to the technical plan. After hoisting the precast double-sided ribbed beam integrated slab in sections and modules, check the elevation of the top surface of the precast double-sided ribbed beam integrated slab in each section. If it is found that the precast double-sided ribbed beam integrated slab has a large error, or its lower truss bars, embedded bolts are deformed, or other special conditions affect, small jacks can be used to adjust at both ends of the precast double-sided ribbed beam integrated slab, and tighten the positioning nuts to re-position;

[0026] Step S5: Install the fixing nuts and process the installation grooves:

[0027] After the precast double-sided ribbed beam integrated slab is hoisted in sections and modules and in place, the installation grooves, reserved holes, etc. on its upper part are cleaned again. The reserved holes are grouted, and the fixing nuts are screwed one by one in the installation grooves at the top of the precast double-sided ribbed beam integrated slab. The fixing nuts are fixed by screwing twice. That is, more than 80% can be screwed for the first time. After the fixing nuts in each section are installed, after rechecking the in-place situation of the precast double-sided ribbed beam integrated slab, the second final screwing is carried out. For the screwed fixing nuts, anti-corrosion paint is applied to the gaps in the installation grooves, and then filled with slightly expanded high-strength mortar, or directly filled and solidified with asphalt glue at one time. During this construction process, the overflow holes on the upper part of the in-place precast double-sided ribbed beam integrated slab are temporarily blocked, and no sundries are allowed to fall into the cavity below the in-place precast double-sided ribbed beam integrated slab to ensure the construction quality of the subsequent high-pressure grouting fine aggregate concrete, and the process acceptance and records are done well;

[0028] Step S6: Install the aluminum formwork and grout:

[0029] After the installation of the fixing nuts is completed, it marks the end of the on-site installation of the precast components of the overall road structure. The aluminum formwork is installed on the outside of the overhead part between the reinforced concrete pier column and the precast double-sided ribbed beam integrated slab. The corner area of the aluminum formwork is provided with connection holes, and the lower part is provided with grouting holes. The outer sides of the reinforced concrete pier column and the precast double-sided ribbed beam integrated slab are pre-embedded with internal thread connectors when they are prefabricated and formed in the PC factory. The aluminum formwork is quickly installed on-site by screwing bolts. After the installation of the aluminum formwork is completed, high-pressure grouting can be carried out through the grouting holes at the lower part of the aluminum formwork, grouting diagonally. When the slurry flows out from the overflow holes at the top of the other precast double-sided ribbed beam integrated slab in the module, it means that the grouting work is completed. To prevent slurry leakage during the pouring process of the fine aggregate concrete, flexible coil strips can be set on the contact surfaces of the aluminum formwork with the reinforced concrete pier column and the precast double-sided ribbed beam integrated slab during the installation of the aluminum formwork. The coil strips are pasted on the sides of the reinforced concrete pier column and the precast double-sided ribbed beam integrated slab at the installation position of the aluminum formwork by cold bonding method. The on-site high-pressure grouting material uses self-compacting slightly expanded low-shrinkage fine aggregate concrete grouting material, and the grouting operation is completed at one time without leaving construction joints. For the grouting work, when necessary, a high-pressure secondary grouting or multiple grouting processes are adopted to ensure the construction quality of the concealed project of the structural grouting;

[0030] Step S7: Joint treatment and the first paving of the asphalt surface layer:

[0031] The joint between adjacent precast double-sided ribbed beam integrated slabs is designed to be no less than 20 mm. The joint between precast double-sided ribbed beam integrated slabs is a free end, which belongs to the technological joint of on-site structural installation and is also the deformation joint and temperature joint of the structure after subsequent traffic. The joint between adjacent precast double-sided ribbed beam integrated slabs shall be strictly processed according to the technical scheme. There shall be no hard debris left in the joint, and the joint shall be kept clean and the lines shall be smooth. One additional full-length steel bar not less than Φ16 + asphalt glue perfusion shall be used for filling and compacting. After the joint between adjacent precast double-sided ribbed beam integrated slabs is properly processed, the first comprehensive paving work of the upper asphalt surface layer can be carried out. The thickness of the first paving of the asphalt surface layer is 1 / 3 to 1 / 2 of the designed surface layer thickness. During the on-site construction process, the asphalt surface layer shall not be paved in the precast curb beam areas at both ends of the precast double-sided ribbed beam integrated slab. After the subsequent installation of the precast curb beam is completed, the comprehensive paving of the asphalt surface layer shall be carried out in place.

[0032] Step S8: Hoisting and fixing of precast curb beam:

[0033] After the first paving of the asphalt surface layer is completed, the hoisting work of the precast curb beam shall be carried out according to the technical scheme. Hoisting shall be carried out in sections. Reserved perforations and installation grooves are provided at both ends of each section of the precast curb beam. The on-site hoisting process is the same as that of the precast double-sided ribbed beam integrated slab. After each section of the precast curb beam is hoisted in sections and modules, the reserved perforations and the voids in the installation grooves at the top after the perforations are in place shall be filled with asphalt glue. The top of the precast curb beam shall be leveled with mortar and a certain drainage slope shall be left.

[0034] Step S9: Secondary paving of asphalt surface layer:

[0035] After the hoisting of the precast curb beam is completed, a preliminary acceptance of the overall structure shall be carried out. The top elevation of the asphalt surface layer in each section shall be measured and marked by using a level or total station. The top elevation of the asphalt surface layer shall be measured and marked on the inner side of the precast curb beam. The elevation position line and control line shall be snapped. The position line at the top of the asphalt surface layer shall be used as the standard line for secondary paving, and the control line shall be used as the verification line or acceptance marking line for the forming of the secondary paving of the asphalt surface layer. The completion of the secondary paving of the asphalt surface layer represents the end of all the construction procedures of the main structure. Strengthen the maintenance and finished product protection.

[0036] Step S10: Installation of other accessory components and project acceptance:

[0037] During the on-site construction process, precast grooves are used for the drainage components outside the road structure. The precast grooves are also fabricated and formed in the prefabricated PC factory. The designed length of each section of the precast groove is the same as the width of each section of the precast double-sided ribbed beam integrated slab in the same direction. Bolt connection holes are embedded on the precast groove, and the positions of the bolt connection holes correspond one-to-one with the installation points of the aluminum formwork on the outer side of the precast double-sided ribbed beam integrated slab. With supporting design, it better realizes the rapid installation of the precast groove and other accessory components on-site; a pipeline connection port is added to the precast groove, which is mainly used for road surface drainage and rainwater collection, and the road surface rainwater is concentrated and discharged into the river around the road; in areas with less rain, the water collection function of the precast groove can also concentrate and guide the rainwater into the surrounding crop irrigation channels for subsequent crop irrigation water; after all the road structure construction is completed, on the basis of the self-inspection of the construction unit being qualified, a comprehensive acceptance work will be carried out together with various units.

[0038] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0039] ① The structure of the present invention is reasonably designed, and the anti-vibration effect of the structure is remarkable; the truss bars and embedded rivets strengthen the connection between the precast double-sided ribbed beam integrated slab and the lower part, thereby enhancing the bearing capacity of the overall structural system.

[0040] ② The present invention adopts the assembly integrated construction technology, with mechanical hoisting, accurate positioning of components, greatly reducing the labor cost, saving the construction period, environmental protection, meeting the requirements of the green building standard, and having good economic and social benefits. Description of the Drawings

[0041] Figure 1 is a schematic cross-sectional view of the road structure of the present invention;

[0042] Figure 2 is a process flow chart of the road structure construction method of the present invention;

[0043] Reference numerals in the drawings: 1 - Reinforced concrete pier column, 2 - High-strength bolt rod, 3 - Precast double-sided ribbed beam integrated slab, 4 - Precast curb beam, 5 - Asphalt surface course, 6 - Pier column longitudinal reinforcement, 7 - Anchor plate, 8 - Truss bar, 9 - Embedded rivet, 10 - Installation groove, 11 - Overflow hole, 12 - Cushion layer, 13 - Reserved perforation, 14 - Locknut, 15 - Fixed nut. Detailed Embodiments

[0044] Please refer to Figure 1, in the embodiments of the present invention, an adjustable elevation modular prefabricated road structure is disclosed, which includes a reinforced concrete pier column 1, a high-strength bolt rod 2, a precast double-sided ribbed beam integrated slab 3, a precast curb beam 4, and an asphalt surface layer 5. High-strength bolt rods 2 and extended pier longitudinal bars 6 are embedded inside the reinforced concrete pier column 1. The high-strength bolt rods 2 pass through the precast double-sided ribbed beam integrated slab 3 and the precast curb beam 4. Fixed nuts 15 are provided on the high-strength bolt rods 2, and the fixed nuts 15 fix the precast double-sided ribbed beam integrated slab 3 and the precast curb beam 4 on the high-strength bolt rods 2. Truss bars 8 and embedded rivets 9 are also provided at the lower part of the precast double-sided ribbed beam integrated slab 3. Fine aggregate concrete is poured into the internal cavity of the overall structure by the high-pressure grouting method.

[0045] The overall structure adopts the design concept of "prefabrication and assembly, pier column support, nut pre-leveling, efficient positioning of the integrated slab, and high-pressure grouting", and strengthens the research and application of new technologies. The specific detailed solutions are as follows:

[0046] The minimum cross-sectional dimension of the reinforced concrete pier column 1 is not less than 250 mm, and the height is not less than 450 mm. A concrete cushion 12 is provided below the reinforced concrete pier column 1. The thickness of the cushion 12 is not less than 60 mm, and fine aggregate concrete above C20 is used. The width of the cushion 12 exceeds the side of the reinforced concrete pier column 1 by not less than 120 mm on each side.

[0047] The reinforced concrete pier column 1 and the high-strength bolt rod 2 are integrally prefabricated and formed in a PC factory. The high-strength bolt rod 2 extends into the reinforced concrete pier column 1 by at least 2 / 3 of the height of the reinforced concrete pier column 1 and not less than 300 mm.

[0048] The pier longitudinal bars 6 on both sides of the reinforced concrete pier column 1 extend out and are anchored into the cavity of the overall structure. The anchorage length is not less than 40d (d is the diameter of the pier longitudinal bar 6) and not less than 1000 m. An anchorage plate 7 is provided at the end of the extended pier longitudinal bar 6, and the number of the anchorage plates 7 is set at 100% along with the pier longitudinal bar 6. To adapt to various complex geological conditions and improve the durability of the structure, the protective layer thickness of the pier longitudinal bar 6 is not less than 30 mm.

[0049] The diameter of the high-strength bolt rod 2 is not less than 30 mm. Its cutting length is determined comprehensively according to the designed road surface elevation, the top elevation of the precast curb beam 4, the installation and positioning elevation of the precast double-sided ribbed beam integrated slab 3, the length of the high-strength bolt rod 2 inserted into the reinforced concrete pier column 1, etc. The top of the high-strength bolt rod 2 should be flush with the top surface elevation of the precast curb beam 4, and the maximum error shall not be greater than +10 mm.

[0050] A positioning nut 14 is provided on the high-strength bolt rod 2. The elevation after tightening (top elevation) of the positioning nut 14 on the high-strength bolt rod 2 is the placement elevation at the end of the precast double-sided ribbed beam integrated slab 3. Therefore, when designing the high-strength bolt rod 2, the layout range of the external thread for nut placement on it should meet the construction requirements. When necessary, BIM technology software can be used to simulate the installation according to the road alignment trend to check the accuracy of its position relationship.

[0051] The precast double-sided ribbed beam integrated slab 3 is formed by integrating the beam and slab in the precast PC factory, and is composed of a supporting beam at the end and an inverted composite slab in the middle. The composite slab is provided with slurry overflow holes 11. The cross-sectional size of the supporting beam at the end of the precast double-sided ribbed beam integrated slab 3 is not less than 200mm×300mm, the diameter of the longitudinal stressed steel bars is not less than 22mm, the diameter of the stirrups is not less than 8mm, and the spacing is not more than 150mm. The stirrups within 500mm at each end of the precast double-sided ribbed beam integrated slab 3 should be densely arranged, and the stirrup spacing in the dense area is not more than 100mm. Due to the "reverse arch force" of the foundation soil on the overall structure of the road project, the thickness of the precast part of the middle composite slab is not less than 70mm, and the internal double-layer and double-direction steel bars are arranged. The diameter of the distribution steel bars is not less than 12mm, which is determined by comprehensive design based on aspects such as the nature of the project, geological environment, soil layer distribution, traffic load, and traffic flow.

[0052] A reserved perforation 13 for connecting with the high-strength bolt rod 2 is provided in the supporting beam at the end of the precast double-sided ribbed beam integrated slab 3. The reserved perforation 13 is formed by pre-embedding a steel sleeve. The steel sleeve is fixed and formed with the concrete of the precast double-sided ribbed beam integrated slab 3 in the PC factory. The diameter of the reserved perforation 13 is 2mm - 4mm larger than the diameter of the high-strength bolt rod 2. A fixing nut 15 is also provided on the high-strength bolt rod 2. An installation groove 10 is provided at the top of the supporting beam. The installation groove 10 is mainly used to fix the precast double-sided ribbed beam integrated slab 3 and the high-strength bolt rod 2. It has an internal groove design, which does not affect the installation of the overall structure and the appearance quality index, and can accommodate the fixing nut 15. The installation groove 10 can be set as circular or square, and the minimum size is 10mm - 12mm larger than the outer diameter of the fixing nut 15. The internal gap after fixed connection is filled densely with asphalt, which not only achieves the installation and fixing effect but also takes into account the anti-corrosion effect of the fixing nut 15.

[0053] The lower part of the precast double-sided ribbed beam integrated slab 3 is designed with truss bars 8 arranged in a vertical and horizontal two-way manner. The diameter of the truss bars 8 is designed according to the specifications, and the spacing of the truss bars 8 does not exceed 800mm. The embedded rivets 9 are designed with I-shaped steel, and the length embedded in the composite slab is not less than 1 / 2 of the thickness of the precast part of the composite slab and not less than 35mm, and the length extending into the lower grout is not less than 120mm. The truss bars 8 and the embedded rivets 9 mainly strengthen the connection between the precast double-sided ribbed beam integrated slab 3 and the lower part, thereby enhancing the bearing capacity of the overall structural system.

[0054] The precast curb beam 4 is also prefabricated and formed in the precast PC factory together with the reinforced concrete pier column 1 and the precast double-sided ribbed beam integrated slab 3. There are no special requirements for the cross-sectional dimensions of the precast curb beam 4, which are determined according to the actual situation of the project. The internal longitudinal stressed steel bars are arranged not less than 4Φ20. The length of each precast curb beam 4 does not exceed 4.5 m, and the stress requirements during the hoisting process of the precast curb beam 4 should be satisfied. The precast curb beam 4 is also provided with reserved perforations 13 and installation grooves 10 inside. The installation of the overall prefabricated component is completed through fixing nuts 15 at the top. The internal treatment method of the installation groove 10 at the top of the precast curb beam 4 is the same as the specific method of the precast double-sided ribbed beam integrated slab 3.

[0055] There is a fine aggregate concrete grouting layer in the internal cavity after the installation of the overall component. The concrete strength is not less than C30, and self-compacting micro-expansion fine aggregate concrete grouting material is used.

[0056] The construction method of the above structure adopts the core technical solution of "prefabrication and assembly, pier support, nut pre-leveling, efficient positioning of the integrated slab, and high-pressure grouting". The construction process flow is as follows:

[0057] Subgrade treatment, excavation of pier grooves --- cushion casting, hoisting and positioning of reinforced concrete pier columns --- elevation measurement, installation of positioning nuts --- segmental and modular hoisting of precast double-sided ribbed beam integrated slabs --- installation of fixing nuts, internal treatment in the installation grooves --- formwork installation and grouting --- joint treatment, first paving of asphalt surface layer --- hoisting and fixing of precast curb beams --- second paving of asphalt surface layer --- installation of other accessory components and project acceptance.

[0058] The specific technical solutions of the construction process flow are as follows:

[0059] Step S1: Subgrade treatment, excavation of pier grooves

[0060] First, conduct measurement and layout to determine the road alignment and subgrade excavation elevation. The subgrade is reinforced by the resource recycling and utilization of mixed materials such as fly ash slag, slag, and construction waste solid particles. According to the drawings and technical solutions, strictly control the top elevation after subgrade reinforcement treatment, including indicators such as the elevation of positioning nuts, the top elevation of precast double-sided ribbed beam integrated slabs, the top elevation of precast curb beams, and the pouring volume of fine aggregate concrete in the high-pressure grouting layer in subsequent processes. Reinforced concrete piers are used as supporting components for the overall road structure on-site. After measuring and laying out the plane positions of each pier, the excavation work of the holes for each reinforced concrete pier can be carried out. The reinforced concrete piers can be formed by precast or cast-in-place methods. In complex geological conditions such as sandy soil, silty soil, and abundant groundwater, the cast-in-place method can be selected. The hollow steel pipe piles are used for hole expansion, and concrete is poured inside, that is, the soil is squeezed to form holes, the steel reinforcement cages are hoisted and placed, the concrete is poured, and the piles are pulled out for turnover to carry out the on-site construction of reinforced concrete piers. This plan does not require a cushion layer. Since the height of the precast reinforced concrete piers does not reach 2m, the manual excavation method can be selected for pier trench excavation in a relatively hard geological environment. The size of the excavated pier trench should meet the design requirements and leave enough working space. Immediately pour cushion concrete after pier trench excavation, minimize the exposure time of the pier trench, and do a good job in the acceptance and record of the process procedures.

[0061] Step S2: Pour the cushion layer and hoist the reinforced concrete pier into place

[0062] After the pier trench excavation is completed, the cushion concrete can be poured according to the technical solution. To save the construction period, the reinforced concrete piers are preferably precast PC components. During on-site construction, directly hoist each precast reinforced concrete pier into place by machine, and do a good job in protecting the high-strength bolt rods inside the reinforced concrete piers and the longitudinal pier reinforcement at their tops. Problems such as damage to precast components, excessive deformation of high-strength bolt rods or longitudinal pier reinforcement, and loss of the anchorage plate at the end of the longitudinal pier reinforcement shall not occur. The extended longitudinal pier reinforcement on the top surface of the reinforced concrete pier should meet a certain anchorage length according to the drawing requirements, and the reinforcement anchored into the installation structure cavity should not be less than 80% of the number of longitudinal pier reinforcement in the reinforced concrete pier. Before hoisting the reinforced concrete pier, first review the top elevation of the cushion layer to ensure that the error is controllable. During the hoisting process, use the method of drawing positioning lines and control lines for plane positioning, and use a level or total station to review the elevation of the reinforced concrete pier in place. According to the road alignment, use a theodolite to control the plane positions of each reinforced concrete pier after hoisting in sections.

[0063] Step S3: Measure the elevation and install the positioning nuts

[0064] After the reinforced concrete pier column is hoisted and positioned in place, check and adjust the deformation of the high-strength bolt rods on the reinforced concrete pier column. Use a level or total station to measure the elevation of the positioning nuts, and mark the elevation of the top surface of the positioning nuts on each high-strength bolt rod. The position relationship of the high-strength bolt rods, the elevation measurement of the positioning nuts, the fixed nuts, etc. in adjacent construction sections can be operated synchronously. According to the road alignment, focus on measuring the elevation of the positioning nuts in place. It should be emphasized that the elevation of the top surface of the positioning nuts on the reinforced concrete pier column is the elevation of the on-site hoisting and positioning in place of the precast double-sided ribbed beam integrated slab in the subsequent process. The elevation error of the top surface of the positioning nuts on each reinforced concrete pier column does not exceed 2 mm. After the on-site elevation measurement, mark it with red paint. The elevation measurement marks are preferably facing the outside of the road for the convenience of installing the positioning nuts one by one on site. All elevation measurement marks are in the same direction and shall not be marked randomly to avoid affecting the operation of on-site technicians. After all the elevation measurement marks of the top surface of the positioning nuts in the construction section are completed, the installation of the positioning nuts can be carried out. The operator should tighten the positioning nuts on site so that the red mark is faintly visible on its top surface. Regardless of the design of several lanes, the elevation of the top surface of the positioning nuts on all the reinforced concrete pier columns in the transverse direction of the road should be the same. Install accurately on site according to the construction drawings and technical solutions, and assign special personnel to stand by to do a good job in the process acceptance and record work.

[0065] Step S4: Hoist the precast double-sided ribbed beam integrated slab in sections and modules

[0066] After all the elevations of the top surfaces of the positioning nuts on each reinforced concrete pier column are marked and the process acceptance work is done, and after cleaning each reserved hole, the precast double-sided ribbed beam integrated slab can be hoisted in sections and modules. In the case of multi-lane design, the construction can be carried out in a flowing manner from the middle precast double-sided ribbed beam integrated slab to the ends, hoisting the precast double-sided ribbed beam integrated slab one by one, and concentrating all the errors due to design, construction, measurement, etc. at the ends for unified treatment, without affecting the implementation of the overall hoisting plan. During the hoisting of the precast double-sided ribbed beam integrated slab, it is necessary to do a good job in protecting its lower truss bars and embedded bolts. It is not allowed to cause excessive deformation of its lower truss bars and embedded bolts during stacking, hoisting, and positioning processes, which may affect the subsequent construction quality. In the early stage, the lower part of the precast double-sided ribbed beam integrated slab is appropriately suspended along the roadside by adding wooden crossbeams. Add wooden crossbeams at the lower part of the supporting beams at both ends of the precast double-sided ribbed beam integrated slab. Set the walking route of the mechanical equipment and the stacking area of the precast double-sided ribbed beam integrated slab during on-site hoisting, and use the two-point common arc method to hoist it in place at one time to save the construction period. The hoisting machinery shall not walk under load and shall strictly execute the hoisting task according to the technical plan. After hoisting the precast double-sided ribbed beam integrated slab in sections and modules, check the elevation of the top surface of the precast double-sided ribbed beam integrated slab in each section. If it is found that the error of the precast double-sided ribbed beam integrated slab is large, or the deformation of its lower truss bars and embedded bolts, or other special working conditions affect, small jacks can be used to adjust at both ends of the precast double-sided ribbed beam integrated slab, and tighten the positioning nuts to re-position.

[0067] Step S5: Install the fixing nuts and process the installation grooves

[0068] After the precast double-sided ribbed beam integrated slab is hoisted in segments and modules and in place, the installation grooves, reserved holes, etc. on its upper part are cleaned again. The reserved holes are grouted, and the fixing nuts are screwed one by one in the installation grooves at the top of the precast double-sided ribbed beam integrated slab. The fixing nuts are fixed by screwing twice. That is, more than 80% can be screwed for the first time. After the fixing nuts in each section are installed, and after rechecking the in-place situation of the precast double-sided ribbed beam integrated slab, the second final screwing is carried out. For the screwed fixing nuts, anti-corrosion paint is applied to the gaps in the installation grooves, and then filled with slightly expanded high-strength mortar, or directly filled and solidified with asphalt glue at one time. During this construction process, the overflow holes on the upper part of the in-place precast double-sided ribbed beam integrated slab are temporarily blocked, and no sundries can fall into the cavity under the in-place precast double-sided ribbed beam integrated slab, ensuring the construction quality of the subsequent high-pressure grouting fine aggregate concrete, and doing a good job in process acceptance and records.

[0069] Step S6: Install the aluminum formwork and grout

[0070] After the installation of the fixing nuts is completed, it marks the end of the on-site installation of the precast components of the overall road structure. The aluminum formwork is installed on the outer side of the overhead part between the reinforced concrete pier column and the precast double-sided ribbed beam integrated slab. The corner area of the aluminum formwork is provided with connection holes, and the lower part is provided with grouting holes. The inner threaded connectors are pre-embedded on the outer sides of the reinforced concrete pier column and the precast double-sided ribbed beam integrated slab when they are prefabricated and formed in the PC factory. The aluminum formwork is quickly installed on-site by screwing bolts. After the installation of the aluminum formwork is completed, high-pressure grouting can be carried out through the grouting holes at the lower part of the aluminum formwork, grouting diagonally. When the slurry flows out from the overflow holes at the top of the other precast double-sided ribbed beam integrated slab in the module, it means that the grouting work is completed. To prevent slurry leakage during the pouring process of the fine aggregate concrete, flexible coil strips can be set on the contact surfaces between the aluminum formwork and the reinforced concrete pier column and the precast double-sided ribbed beam integrated slab during the installation of the aluminum formwork. The coil strips are pasted on the sides of the reinforced concrete pier column and the precast double-sided ribbed beam integrated slab at the installation position of the aluminum formwork by cold adhesion method. The on-site high-pressure grouting material uses self-compacting slightly expanded low-shrinkage fine aggregate concrete grouting material, and the grouting operation is completed at one time without leaving construction joints. For the grouting work, when necessary, the high-pressure secondary grouting or multiple grouting processes are adopted to ensure the construction quality of the concealed project of the structural grouting.

[0071] Step S7: Joint treatment and the first paving of the asphalt surface course

[0072] The joint between two adjacent precast double-sided ribbed beam integrated slabs is designed to be no less than 20 mm. The joint between precast double-sided ribbed beam integrated slabs serves as a free end, which is a technological joint for on-site structural installation, and also a deformation joint and temperature joint of the structure after subsequent traffic. The joint between two adjacent precast double-sided ribbed beam integrated slabs shall be treated strictly in accordance with the technical plan. There shall be no hard debris left in the joint, and the joint shall be kept clean and the lines shall be smooth. One additional full-length steel bar not less than Φ16 + asphalt glue perfusion shall be used for filling and compacting. After the joint between two adjacent precast double-sided ribbed beam integrated slabs is properly treated, the first comprehensive paving work of the upper asphalt surface layer can be carried out. The thickness of the first paving of the asphalt surface layer is 1 / 3 to 1 / 2 of the designed surface layer thickness. During the on-site construction process, the paving of the asphalt surface layer may not be carried out in the precast curb beam areas at both ends of the precast double-sided ribbed beam integrated slab. After the subsequent installation of the precast curb beam is completed, the comprehensive paving of the asphalt surface layer shall be carried out in place.

[0073] Step S8: Hoisting and fixing of precast curb beam

[0074] After the first paving of the asphalt surface layer is completed, the hoisting work of the precast curb beam shall be carried out according to the technical plan. Hoisting shall be carried out in sections. Reserved perforations and installation grooves are provided at both ends of each section of the precast curb beam. The on-site hoisting process is the same as that of the precast double-sided ribbed beam integrated slab. After each section of the precast curb beam is hoisted in sections and modules, the reserved perforations and the gaps in the top installation grooves after the perforations are in place shall be filled with asphalt glue. The top of the precast curb beam shall be leveled with mortar and a certain drainage slope shall be left.

[0075] Step S9: Secondary paving of asphalt surface layer

[0076] After the hoisting of the precast curb beam is completed, a preliminary acceptance of the overall structure shall be carried out. The top elevation of the asphalt surface layer in each section shall be measured and marked using a level or total station. The top elevation of the asphalt surface layer shall be measured and marked on the inner side of the precast curb beam, and the elevation position line and control line shall be snapped. The position line at the top of the asphalt surface layer shall be used as the standard line for secondary paving, and the control line shall be used as the verification line or acceptance marking line for the formation of the secondary paving of the asphalt surface layer. The completion of the secondary paving of the asphalt surface layer represents the complete end of the main structure construction process. Strengthen the maintenance and finished product protection

[0077] Step S10: Installation of other accessory components and project acceptance

[0078] During the on-site construction process, precast grooves are used for the drainage components outside the road structure. The precast grooves are also fabricated and formed in the prefabricated PC factory. The designed length of each section of the precast groove is the same as the width of each section of the precast double-sided ribbed beam integrated slab in the same direction. Bolt connection holes are embedded in the precast grooves, and the positions of the bolt connection holes correspond one-to-one with the aluminum form installation points on the outer side of the precast double-sided ribbed beam integrated slab. With supporting design, it better realizes the rapid installation of precast grooves and other accessory components on site. A pipeline connection port is added to the precast groove, which is mainly used for road surface drainage and rainwater collection, and concentrates the road surface rainwater into the river around the road. In areas with less rainfall, the water collection function of the precast groove can also concentrate and guide the rainwater into the surrounding crop irrigation channels for subsequent crop irrigation water. After all the road structure construction is completed, on the basis of the self-inspection qualification of the construction unit, a comprehensive acceptance work is carried out together with various units.

[0079] In summary, the structure of the present invention is reasonably designed, the anti-vibration effect of the structure is remarkable, the assembly integrated construction technology is adopted, mechanical hoisting is carried out, and the components are accurately positioned, greatly reducing the labor cost, saving the construction period, protecting the environment, meeting the requirements of the green building standard, and having good economic and social benefits.

[0080] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used 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 recorded 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. A modular prefabricated road structure with adjustable elevation, characterized by: It includes reinforced concrete piers, high-strength bolt rods, prefabricated double-sided rib beam integrated plates, prefabricated curb beams and asphalt surface layers. A cushion layer is provided under the reinforced concrete piers, in which the high-strength bolt rods and the extended pier longitudinal reinforcement are pre-embedded, and anchor plates are provided at the ends of the pier longitudinal reinforcements. The prefabricated double-sided rib beam integrated plate comprises a supporting beam at the end and an inverted composite plate in the middle, wherein the composite plate is provided with a grouting hole, and the lower part of the prefabricated double-sided rib beam integrated plate is also provided with a truss rib and a pre-embedded rivet bolt, wherein the truss rib is arranged in both longitudinal and transverse directions; The supporting beam and the prefabricated curb beam are both provided with reserved through-holes, the high-strength bolt rod passes through the reserved through-holes, the high-strength bolt rod is provided with a fixing nut, the tops of the supporting beam and the prefabricated curb beam are both provided with mounting grooves, the mounting grooves contain the fixing nut, and the fixing nut fixes the prefabricated double-sided rib beam integrated plate and the prefabricated curb beam to the high-strength bolt rod; Fine stone concrete is poured into the internal cavity of the overall structure by high-pressure grouting method.

2. The adjustable elevation modular assembled road structure according to claim 1 is characterized in that: The minimum cross-sectional dimension of the reinforced concrete pier shall not be less than 250mm, and the height shall not be less than 450mm; the cushion layer shall be made of fine stone concrete of C20 or above, with a thickness of not less than 60mm, and the cushion layer width shall exceed the side of the reinforced concrete pier by not less than 120mm on each side; the reinforced concrete pier and the high-strength bolt rods shall be prefabricated in an integrated manner in the PC factory, and the high-strength bolt rods shall extend into the reinforced concrete pier for at least 2 / 3 of the height of the reinforced concrete pier and not less than 300mm; the longitudinal reinforcements of the pier on both sides of the reinforced concrete pier shall extend outward and be anchored into the cavity of the overall structure, with an anchoring length of not less than 40d and not less than 1000m, where d is the diameter of the longitudinal reinforcement of the pier; the number of anchor plates shall be set with 100% of the longitudinal reinforcement of the pier, and the thickness of the protective layer of the longitudinal reinforcement of the pier shall not be less than 30mm.

3. The adjustable elevation modular assembled road structure according to claim 1 is characterized by: The diameter of the high-strength bolt rod is not less than 30 mm, and the top is flush with the top surface elevation of the prefabricated curb beam; a positioning nut is provided on the high-strength bolt rod, and the elevation of the positioning nut after being tightened on the high-strength bolt rod is the positioning elevation of the end of the prefabricated double-sided rib beam integrated plate.

4. The adjustable elevation modular assembled road structure according to claim 1 is characterized by: The cross-sectional size of the supporting beam shall not be less than 200mm×300mm, the diameter of the longitudinal force-bearing steel bar shall not be less than 22mm, the diameter of the stirrup shall not be less than 8mm, and the spacing shall not be greater than 150mm. The stirrups within 500mm of the end of the prefabricated double-sided rib beam integrated plate shall be densely arranged, and the spacing of the stirrups in the dense area shall not be greater than 100mm; The thickness of the prefabricated part of the composite slab is not less than 70mm, and the internal double-layer bidirectional steel bars are arranged, and the diameter of the distributed steel bars is not less than 12mm; the reserved perforations are pre-buried with steel sleeves, and the steel sleeves are fixedly formed by concrete pouring with the prefabricated bilateral rib beam integrated slab in the PC factory, and the diameter of the reserved perforations is 2mm to 4mm larger than the diameter of the high-strength bolt rod; The installation groove is circular or square, and its minimum size is 10 mm to 12 mm larger than the outer diameter of the fixing nut. The internal gap after the fixed connection is densely filled with asphalt.

5. The adjustable elevation modular assembled road structure according to claim 1 is characterized by: The diameter of the truss reinforcement is designed in accordance with the specifications, the spacing of the truss reinforcement does not exceed 800mm, the embedded rivets are designed with I-beams, the length embedded inside the composite plate is not less than 1 / 2 of the thickness of the prefabricated part of the composite plate and not less than 35mm, and the length extending outward into the lower grouting material is not less than 120mm.

6. The adjustable elevation modular assembled road structure according to claim 1 is characterized by: The prefabricated curb beam is prefabricated in an assembled PC factory, the internal longitudinal stress-bearing steel bars are arranged not less than 4Φ20, the length of each section of the prefabricated curb beam does not exceed 4.5m, and meets the stress requirements of the prefabricated curb beam hoisting process.

7. A construction method for an adjustable elevation modular assembled road structure, characterized in that: The core technical solution of "prefabrication and assembly, pier support, nut pre-leveling, integrated plate efficient positioning, high-pressure grouting" is adopted, and the construction process is as follows: Roadbed treatment, pier trench excavation---cushion pouring, reinforced concrete pier column hoisting into place---elevation measurement, positioning nut installation---prefabricated double-sided rib beam integrated plate hoisting in sections and modules---fixing nut installation, groove treatment---aluminum mold installation and grouting---joint treatment, asphalt surface layer first paving---prefabricated curb beam hoisting and fixing---asphalt surface layer second paving---other auxiliary components installation and project acceptance.

8. The construction method of the adjustable elevation modular assembled road structure according to claim 7 is characterized by: The key technical solutions are as follows: Step S1: Roadbed treatment and trench excavation: First, survey and lay out to determine the road line type and roadbed excavation elevation, and use fly ash, slag, solid particles of construction waste and other mixed materials for resource recycling to reinforce the roadbed; according to the drawings and technical plans, strictly control the top elevation of the roadbed after reinforcement, including the positioning nut elevation in the subsequent process, the top elevation of the prefabricated double-sided rib beam integrated plate, the top elevation of the prefabricated curb beam, and the injection volume of fine stone concrete in the high-pressure grouting layer. Reinforced concrete piers are used on site as the supporting components of the overall road structure. After measuring and laying out the plane positions of each pier, the excavation of the holes of each reinforced concrete pier can be carried out. The reinforced concrete piers can be Prefabrication or cast-in-place molding. In complex geological conditions such as sand, silt, and abundant groundwater, cast-in-place molding can be selected. Holes are enlarged with hollow steel pipe piles, and concrete is poured inside. That is, soil is squeezed to form holes, steel cages are suspended, concrete is poured, and piles are pulled out for on-site construction of reinforced concrete piers. This scheme does not require a cushion layer. Since the height of prefabricated reinforced concrete piers does not reach 2m, manual digging can be selected for pier trench excavation in a relatively hard geological environment. The size of the excavated pier trench should meet the design requirements and leave enough working surface. After the pier trench is excavated, the cushion layer concrete is poured immediately to minimize the exposure time of the pier trench, and the acceptance and record of the process procedures are done well. Step S2: pouring the cushion layer and hoisting the reinforced concrete pier into place: After the excavation of the pier trench is completed, the cushion concrete can be poured according to the technical plan; in order to save construction time, the reinforced concrete pier column should be prefabricated PC components. During the on-site construction, the prefabricated reinforced concrete pier columns should be directly hoisted into place by machinery, and the high-strength bolt rods inside the reinforced concrete pier column and the longitudinal reinforcement of the pier column at the top should be well protected. There should be no problems such as damage to the prefabricated components, excessive deformation of the high-strength bolt rods or the longitudinal reinforcement of the pier column, and loss of the anchor plate at the end of the longitudinal reinforcement of the pier column. The longitudinal reinforcement of the pier column protruding from the top surface of the reinforced concrete pier column should meet a certain anchoring length according to the requirements of the drawings, and the steel bars anchored in the cavity of the installation structure should not be less than 80% of the number of longitudinal reinforcements of the reinforced concrete pier column; before hoisting the reinforced concrete pier column, the elevation of the top of the cushion layer should be checked to ensure that the error is controllable. During the hoisting process, the plane is positioned by using the method of elastic positioning lines and control lines. The elevation of the reinforced concrete pier column in place is checked by using a level or a total station. According to the linear direction of the road, the theodolite is used in sections to control the plane position of each reinforced concrete pier column after hoisting; Step S3: Measure the elevation and install the positioning nut: After the reinforced concrete piers are hoisted into place, the deformation of the high-strength bolt rods on the reinforced concrete piers is checked and adjusted, the elevation of the positioning nuts is measured with a level or a total station, and the top surface positioning nut elevation is marked on each high-strength bolt rod. The position relationship of the high-strength bolt rods, the positioning nuts, the fixed nuts and other elevation measurements in the adjacent construction sections can be performed simultaneously. According to the road line direction, the positioning nut elevation is focused on. It should be emphasized that the top surface elevation of the positioning nuts on the reinforced concrete piers is the on-site hoisting elevation of the prefabricated double-sided rib beam integrated slab in the subsequent process. The top surface elevation error of the positioning nuts on each reinforced concrete pier shall not exceed 2 mm, after the site elevation is measured and set, it should be marked with red paint. The elevation measurement mark should preferably face the outside of the road to facilitate the installation of the locating nuts one by one on site. All elevation measurement marks should be in the same direction and should not be randomly marked to avoid affecting the operation of on-site technical personnel; after all the elevation measurement and setting marks of the top surface of the locating nuts in the construction section are completed, the installation of the locating nuts can be carried out. The operator should tighten the locating nuts on site so that the red mark is faintly visible on the top surface. Regardless of the number of lanes designed, the top surface elevation of the locating nuts on all reinforced concrete piers in the transverse direction of the road should be consistent. Accurate installation should be carried out on site according to the construction drawings and technical plans, and a dedicated person should be stationed to ensure the process acceptance and record work; Step S4: Hoisting prefabricated double-sided rib beam integrated slabs in sections and modules: After marking all the top elevations of the positioning nuts on each reinforced concrete pier, and completing the process acceptance work and cleaning all the reserved holes, the prefabricated double-sided rib beam integrated panels can be hoisted in sections and modules; when multiple lanes are designed, the prefabricated double-sided rib beam integrated panels can be constructed in a continuous manner from the middle to the ends, and the prefabricated double-sided rib beam integrated panels can be hoisted one by one, so that all errors due to design, construction, measurement, etc. are concentrated at the ends for unified processing, which does not affect the implementation of the overall hoisting plan; the hoisting of the prefabricated double-sided rib beam integrated panels requires the protection of the lower truss reinforcement and embedded rivets, and shall not be The stacking, lifting and positioning process causes excessive deformation of the lower truss bars and embedded rivets, which affects the subsequent construction quality. In the early stage of the prefabricated double-sided rib beam integrated plate, wooden beams are added along the side of the road to appropriately suspend the lower part. Wooden beams are added to the lower part of the supporting beams at both ends of the prefabricated double-sided rib beam integrated plate. The walking route of the mechanical equipment and the stacking area of ​​the prefabricated double-sided rib beam integrated plate are set for on-site lifting. The two-point common arc method is used for one-time lifting and positioning, which saves construction time. The lifting machinery is not allowed to travel with load, and the lifting task is carried out strictly in accordance with the technical plan; After the prefabricated double-sided rib beam integrated slab is hoisted in sections and modules, check the top elevation of the prefabricated double-sided rib beam integrated slab in each section. If it is found that the prefabricated double-sided rib beam integrated slab has a large error or its lower truss reinforcement and embedded rivet bolts are deformed or affected by other special working conditions, a small jack can be used to adjust the two ends of the prefabricated double-sided rib beam integrated slab and tighten the positioning nuts to re-position it; Step S5: Install the fixing nut and process the inside of the installation groove: After the prefabricated double-sided rib beam integrated plate is hoisted in place in sections and modules, the installation grooves and reserved holes on the upper part are cleaned for the second time, the reserved holes are grouted, and the fixing nuts are tightened one by one in the installation grooves on the top of the prefabricated double-sided rib beam integrated plate; the fixing nuts are fixed by secondary tightening, that is, more than 80% can be tightened for the first time. After the fixing nuts in each section are installed, the position of the prefabricated double-sided rib beam integrated plate is checked again, and then the secondary final tightening is performed; for the tightened fixing nuts, anti-corrosion paint is applied to the gaps in the installation grooves, and then filled with micro-expansion high-strength mortar, or directly filled with asphalt glue at one time; during this construction process, the overflow holes on the upper part of the prefabricated double-sided rib beam integrated plate that has been in place are temporarily blocked, and debris must not be dropped into the cavity at the lower part of the prefabricated double-sided rib beam integrated plate that has been in place, to ensure the quality of the subsequent high-pressure grouting fine stone concrete construction, and to do a good job of process acceptance and record; Step S6: Aluminum mold installation and grouting: The installation of the fixing nuts is completed, marking the completion of the on-site installation of the prefabricated components of the overall road structure. The aluminum formwork is installed on the outside of the overhead part between the reinforced concrete pier and the prefabricated double-sided rib beam integrated plate. The aluminum formwork is provided with connection holes in the corner area and grouting holes in the lower part. The outer sides of the reinforced concrete pier and the prefabricated double-sided rib beam integrated plate are pre-embedded with internal threaded connectors when they are prefabricated in the PC factory. The aluminum formwork is quickly installed on site by tightening the bolts. After the aluminum formwork is installed, high-pressure grouting and diagonal grouting can be carried out through the grouting holes at the bottom of the aluminum formwork. When the top of the prefabricated double-sided rib beam integrated plate at the other end of the module is The grouting work is completed when slurry is left in the overflow hole at the bottom. To prevent slurry leakage during the pouring of fine stone concrete, flexible coiled material strips can be set on the contact surface between the aluminum formwork and the reinforced concrete pier column and the prefabricated double-sided rib beam integrated plate when the aluminum formwork is installed. The coiled material strips are attached to the reinforced concrete pier column and the side of the prefabricated double-sided rib beam integrated plate at the installation position of the aluminum formwork by cold bonding. The on-site high-pressure grouting material adopts self-compacting micro-expansion and low-shrinkage fine stone concrete grouting material. The grouting operation is completed at one time without leaving construction joints. For the grouting work, high-pressure secondary grouting or multiple grouting processes are used when necessary to ensure the construction quality of the hidden structure grouting project. Step S7: Joint treatment, first paving of asphalt surface layer: The joint between the prefabricated bilateral rib beam integrated panels of two adjacent modules is designed to be no less than 20mm. The joint between the prefabricated bilateral rib beam integrated panels is a free end, which is a process joint for on-site structural installation, and also a deformation joint and temperature joint of the structure after subsequent traffic opening. The joint between the prefabricated bilateral rib beam integrated panels of two adjacent modules shall be processed strictly in accordance with the technical plan. No hard debris shall be left in the joint. The joint shall be kept clean and the lines shall be smooth. One full-length steel bar of no less than Φ16 + asphalt glue shall be added for filling. After the joint between the prefabricated bilateral rib beam integrated panels of two adjacent modules is properly processed, the first full paving of the upper asphalt surface layer can be carried out. The first paving thickness of the asphalt surface layer is 1 / 3 to 1 / 2 of the designed surface layer thickness. During the on-site construction process, the asphalt surface layer may not be paved in the prefabricated curb beam area at both ends of the prefabricated bilateral rib beam integrated panels. The asphalt surface layer can be fully paved in place after the subsequent prefabricated curb beams are installed. Step S8: Prefabricated curb beam hoisting and fixing: After the first paving of the asphalt surface layer is completed, the prefabricated curb beam is hoisted according to the technical plan; hoisting is carried out in sections, and both ends of each prefabricated curb beam are provided with reserved perforations and installation grooves. The on-site hoisting process is the same as that of the prefabricated double-sided rib beam integrated plate. Each section of the prefabricated curb beam is hoisted in sections and modules. The reserved perforations and the gaps in the top installation grooves after the perforations are in place are filled with asphalt glue. The top of the prefabricated curb beam is smoothed with mortar and a certain drainage slope is left; Step S9: Secondary paving of asphalt surface layer: After the prefabricated curb beam is hoisted, the overall structure is preliminarily inspected and accepted. The elevation of the top surface of the asphalt surface layer in each section is measured and marked using a level or total station. The elevation of the top surface of the asphalt surface layer is measured and marked on the inner side of the prefabricated curb beam. The elevation position line and control line are marked. The position line of the top of the asphalt surface layer is used as the standard line for secondary paving, and the control line is used as the verification line or acceptance line for the secondary paving of the asphalt surface layer. The completion of the secondary paving of the asphalt surface layer represents the completion of all the main structure construction processes, and the maintenance and protection of the finished product are strengthened. Step S10: Installation of other auxiliary components and project acceptance: During the on-site construction process, prefabricated grooves are used for the drainage components on the outside of the road structure. The prefabricated grooves are also manufactured in the assembled PC factory. The designed length of each section of the prefabricated groove is the same as the width of each section of the prefabricated double-sided rib beam integrated plate in the same direction. Bolt connection holes are embedded in the prefabricated grooves. The positions of the bolt connection holes correspond one-to-one with the installation points of the aluminum molds on the outer sides of the prefabricated double-sided rib beam integrated plate. The matching design better realizes the rapid installation of the prefabricated grooves and other auxiliary components on site; the prefabricated grooves are equipped with pipe connection ports, which are mainly used for road drainage and rainwater collection, and the rainwater on the road is concentrated into the river around the road; in areas with less rain, the water collection function of the prefabricated grooves can also concentrate and guide rainwater into the surrounding crop irrigation channels for subsequent crop irrigation water; after the construction of all road structures is completed, on the basis of the qualified self-inspection of the construction unit, a comprehensive acceptance work will be carried out together with various units.

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