Construction method of irregular cobblestone mosaic concrete pavement of automobile test field

Abstract

This invention discloses a construction method for irregular pebble-embedded concrete pavement in an automotive proving ground, comprising the following steps: construction preparation; surveying and setting out; steel mesh layout; elevation control point layout; concrete pouring; pebble embedding; construction joint layout; pavement curing; and joint sealing. This invention, through reasonable optimization of construction techniques, achieves high construction quality and speed, ensuring project progress, saving construction time, improving the accuracy of pavement elevation control and the quality of the finished road, increasing labor efficiency, saving human resources, and reducing costs. The new process achieves a one-time forming rate for irregular pebble-embedded concrete pavement, ensuring pavement forming quality and providing a reference for similar road construction.

Description

Technical Field

[0001] This invention belongs to the technical field of road construction methods, specifically relating to a construction method for irregular pebble-embedded concrete pavement in an automotive proving ground. Background Technology

[0002] Irregularly embedded pebbles of different types are irregularly embedded into cement concrete pavement according to a construction road spectrum. Irregularly embedded pavement is a major special test road with high difficulty in controlling the construction elevation and high requirements for various design indicators. It is mainly used for durability testing of vehicle steering and suspension systems. This special road is mainly an irregular cement concrete test road constrained by the road spectrum, mainly used for fatigue durability, reinforcement durability, and abnormal noise testing of commercial vehicles. The closest construction process to this type of road is the conventional concrete pavement pouring construction process. However, this construction technology cannot guarantee the elevation qualification rate of the irregular concrete pavement undulation position under the road spectrum control, nor can it control the fixed position and elevation qualification rate of the surface pebbles. Therefore, we propose a construction method for irregularly embedded concrete pavement in automotive proving grounds. Summary of the Invention

[0003] The purpose of this invention is to provide a construction method for irregular pebble-embedded concrete pavement in an automotive proving ground, so as to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a method for constructing an irregular pebble-embedded concrete pavement for an automotive proving ground, comprising the following steps:

[0005] Construction preparation: The construction preparation includes data preparation, tool preparation, material preparation and base preparation;

[0006] Surveying and setting out: Use a total station to mark out the road markings at equal intervals on the curb;

[0007] Steel mesh installation: Steel mesh is installed on the concrete base according to the design requirements of the construction drawings;

[0008] Elevation control point layout: The elevation control point layout includes drilling for elevation control point determination and installation of elevation control piles;

[0009] Concrete pouring: The concrete pouring includes concrete pouring and concrete vibration;

[0010] Pebble inlay: The pebble inlay includes pebble positioning, pebble embedding depth, and concrete pavement shaping;

[0011] Construction joint layout: The construction joint layout includes contraction joints and expansion joints;

[0012] Road surface curing: Use water-retaining geotextile to cover and cure irregular cobblestone inlaid road surfaces;

[0013] Crack filling: Use silicone sealant to fill the expansion joints and gaps between adjacent concrete slabs.

[0014] Preferably, the data preparation includes the following steps:

[0015] The irregular pebble-embedded concrete pavement is divided into a commercial vehicle test road and a passenger vehicle test road: the commercial vehicle test road is 580m long and 3.8m wide, with 19,000-20,000 elevation control points; the passenger vehicle test road is 760m long and 3.8m wide, with 25,000-26,000 elevation control points.

[0016] Extract the design road spectrum data table: Based on the design road spectrum, extract the elevation back-calculation data corresponding to the intersection points of the longitudinal 0.4m and the transverse 0.17m, 0.40m, 0.53m, 0.40m, 0.50m, 0.40m, 0.43m, 0.40m, 0.40m, and 0.27m, and assign them as row numbers. Define the top elevation of the curbstone as 0, positive values ​​as the elevation control point relatively higher than the curbstone + a, and negative values ​​as the elevation control point relatively lower than the curbstone - a.

[0017] Road Spectrum Elevation Difference Data Table Compilation: Based on the relative elevation difference H between the elevation controller benchmark beam and the curbstone, and combined with the design road spectrum data table, the road spectrum elevation difference data table is compiled using the inverse elevation difference formula, where the inverse elevation difference formula is: △h=Hh;

[0018] H represents the relative height difference between the reference beam and the curb stones on both sides;

[0019] h represents the design road spectrum elevation control data;

[0020] △h represents the inversely calculated elevation difference data;

[0021] The tool prepared in the tool preparation is an elevation controller;

[0022] The elevation controller includes a stabilizing main frame, a stabilizing reference plate, a reference beam, and an elevation adjusting screw. The elevation controller has a "gate" structure.

[0023] The stabilizing reference plate is fixedly connected to the stabilizing main frame by welding, and the reference beam is connected to the stabilizing main frame by bolts. The reference beam is made of stainless steel and its length is consistent with the road width. The reference beam is engraved with scales that are consistent with the design lateral elevation control spacing. The distance error between the scales on the reference beam is less than 1mm. The bolts are used to adjust the distance between the reference beam and the stabilizing main frame to ensure that the reference beam is parallel to the top surface of the curb stones on both sides.

[0024] The material preparation includes the following steps:

[0025] Pebble classification: Based on the pebble parameters required in the road design specifications, the pebble raw materials are classified into three categories: A, B, and C.

[0026] Pebble preparation: Weigh and classify the raw pebble materials using an electronic scale with an accuracy of 0.2 kg. After classification, rinse the raw pebble materials with a water truck. After rinsing, the surface of the raw pebble materials must not have any impurities that affect the quality.

[0027] The specific steps for grassroots preparation are as follows:

[0028] Use tools to clean the concrete base of the irregular pebble-embedded road. Manually use a handheld gasoline blower to clean the formed concrete base. Before construction, the concrete base must not have sand, gravel, mortar, or garbage and waste soil. After the concrete base is completely cleaned, sprinkle water to moisten it.

[0029] Preferably, the specific steps for the measurement and layout are as follows:

[0030] Using a total station, starting from the starting point, the road curb is marked with 20-meter intervals, with an error of less than 2mm. Within the 20-meter intervals, points are marked with longitudinal intervals of 40cm, and the point numbers are n1, n2, n3, etc., with an error of less than 1mm. The point numbers correspond to the row numbers in the elevation back-calculation data table.

[0031] Preferably, the steel mesh installation includes the following steps:

[0032] The steel mesh is pre-processed and produced at the steel processing plant according to the design requirements of the construction drawings, and then transported to the site for installation.

[0033] At the construction site, an engineering ink marker was used to accurately mark a 5m*3.8m grid on the concrete base according to the irregular pebble inlay road reinforcement diagram. A marker pen and steel tape measure were used to mark the spacing points of the reinforcement. The reinforcement was tied with double wire and twisted securely, with the excess wire end extending into the inside of the reinforcement. The horizontal spacing of the reinforcement mesh was 0.2m and the vertical spacing was 0.15m. The reinforcement mesh was arranged as a single-layer structure, with a reinforcement protective layer thickness of 4-6cm.

[0034] In the longitudinal steel mesh, a dowel bar is installed every 5m and 5m apart. The length of the dowel bar is 0.7m and the dowel bar is a plain round steel bar with a diameter of 25mm.

[0035] After the first layer of reinforcing bars is tied, place spacers on the first layer of reinforcing bars. After the reinforcing bars are tied, check and inspect the spacing between the reinforcing bars.

[0036] Check whether the thickness of the concrete cover at the bottom of the reinforcing bars and the side formwork meets the design requirements. If it does not meet the design requirements, adjust the non-compliant parts.

[0037] Preferably, the specific steps for determining the elevation control points through drilling are as follows:

[0038] Based on the design road map data, mark the drilling points at the construction site according to the standard lines marked by the ink line;

[0039] The specific steps for installing the elevation control piles are as follows: insert 8mm diameter threaded steel bars into the drilled holes. Before inserting the steel bars, inject steel bar fixing adhesive into the holes, and then use a small hammer to vertically hammer the steel bars. The depth of the steel bar holes is 110cm and the steel bars are exposed 23cm.

[0040] After the elevation control stakes are installed, the reverse elevation difference value is marked next to each elevation control stake, based on the back-calculated road spectrum elevation difference data table.

[0041] A 10cm-20cm long PVC sleeve is fitted over each rebar to meet the design road profile requirements. A customized elevation controller is used to adjust the top elevation of the PVC sleeve according to the values ​​marked next to the elevation control stakes in advance. The top elevation of the PVC sleeve is the road design elevation. The adjustment error of the road design elevation is controlled within ±1mm. After the road design elevation is properly adjusted, the 8mm diameter rebar is wrapped tightly and fixed to the PVC sleeve with tape.

[0042] Preferably, the concrete pouring process includes the following steps:

[0043] The road surface layer is poured using a concrete compartmentalized pouring device. The concrete is C35 freeze-thaw resistant concrete with a flexural strength of HF-4.5. The concrete is poured continuously to avoid concentrated dumping that could impact the elevation control piles when it is poured into the formwork.

[0044] The concrete slab is poured continuously using a dowel bar positioner to ensure continuous concrete pouring. After pouring, a end plate is added, with pre-drilled holes located in the middle of the wooden formwork and spaced 60cm apart. Dowel bars are inserted into the end plate, with the insertion length of the dowel bars being half the length of the dowel bar.

[0045] Concrete slabs are poured continuously. If an interval is required during the pouring process, the interval should be shortened to before the initial setting of the previous concrete. The maximum interval for pouring concrete slabs is determined based on the type of cement used, the temperature, and the concrete setting conditions. If the interval for pouring concrete slabs exceeds 1 hour, it should be treated as a construction joint. When the surface of the poured concrete slab is no longer sticky to the touch, the surface of the concrete slab should be roughened.

[0046] When pouring concrete slabs, observe whether the formwork, reinforcing bars, and reserved holes have moved, deformed, or blocked. If any of the above situations are found, they need to be dealt with immediately and repaired before the poured concrete slabs have initially set.

[0047] When the concrete pouring is almost complete, estimate the remaining volume of concrete and contact the commercial concrete batching plant for reasonable scheduling.

[0048] The specific steps for concrete vibration are as follows:

[0049] Concrete vibration should follow the principle of quick insertion and slow withdrawal. The insertion points of the vibrator should be evenly arranged in a quincunx pattern, and the vibrator should be moved point by point in sequence to ensure uniform compaction. The vibration movement distance should be less than 1.5 times the vibration radius, and the vibration movement distance should be 30-40cm. The vibration duration should be until the concrete surface produces laitance, no air bubbles, and no settling.

[0050] Preferably, the specific steps for locating the pebble are as follows:

[0051] Based on the summary of multiple test block constructions, the optimal time for cobblestone embedding is 30-45 minutes after concrete pouring. The cobblestones are then manually embedded to the top of the corresponding elevation control piles according to the cobblestone road map requirements.

[0052] The pebbles were laid out according to the road layout design;

[0053] The specific steps for embedding the pebbles at the specified depth are as follows:

[0054] According to the pebble path requirements, the pebbles are inlaid in the designed positions, and the form of the pebbles is randomly determined during the inlaying process;

[0055] The gravel should be buried at a depth of 2 / 3 of its diameter, with the larger end facing down and the smaller end facing up.

[0056] The specific steps for shaping the concrete pavement are as follows: The shaping process is carried out manually, in three stages.

[0057] After the first pour of concrete on the irregular concrete road surface, the concrete is shaped. During the first shaping, the elevation difference of the set elevation control piles is connected in an arc shape to ensure that the concrete surfaces of every two elevation control piles are connected smoothly.

[0058] The second shaping and finishing process is carried out after the pebbles are inlaid. The shape of the first shaping is used as a reference to refine the concrete pavement after the pebbles are inlaid.

[0059] The third shaping process involves shaping the area around the pebbles before the concrete sets. This third shaping ensures a tight connection between the concrete and the pebbles at the joints after the concrete collapses, guaranteeing a strong bond between the concrete and the pebbles.

[0060] Preferably, the specific steps for applying the contraction joint are as follows:

[0061] After the concrete pavement has set, joints can be cut. One contraction joint should be set every 5m of concrete pavement. The width of the joint should be 4-6mm and the depth of the contraction joint should be greater than 1 / 3 of the thickness of the poured slab. A dowel bar with a diameter of 25mm should be set at the contraction joint. The length of the dowel bar should be 45-55cm and the spacing between the dowel bars should be 55-65cm. One end of the dowel bar should be coated with asphalt and wrapped with polyethylene film.

[0062] The specific steps for the expansion joint are as follows: one expansion joint is set every 200m of concrete pavement. The expansion joint uses a 2cm joint filler board. The dowel bar is installed in the same way as the contraction joint steps described above. The joint is filled to a depth of 30-40mm.

[0063] When contraction joints, expansion joints, and pebbles conflict, adjust the position of the expansion joints and contraction joints.

[0064] Preferably, the specific steps of the road surface maintenance are as follows:

[0065] After the irregular pebble-embedded pavement has been poured and embedded, it is covered with water-retaining geotextile for curing. The number of times the pavement is sprayed with water during the curing period depends on the natural temperature of the day, and the surface is kept moist at all times. The curing time is more than 7 days.

[0066] Preferably, the crack sealing includes the following steps:

[0067] Remove the extruded polystyrene board and clear away debris. Use silicone sealant to install standard basalt bricks, ensuring the shrinkage and elevation requirements between adjacent boards.

[0068] Expansion joints and gaps between adjacent concrete slabs are filled with silicone sealant. Before filling, debris inside the joints must be cleaned, and the sponge strips should be filled tightly. The filling depth should be consistent with the original depth of the expansion joint.

[0069] Compared with the prior art, the beneficial effects of the present invention are:

[0070] This invention optimizes construction processes to achieve high-quality and fast construction, ensuring project progress, saving construction time, improving road elevation control accuracy and finished road quality, increasing labor efficiency, saving human resources, and reducing costs. The new process achieves a one-time forming rate for irregular pebble-embedded concrete pavement, ensuring pavement forming quality and providing a reference for similar road construction. Attached Figure Description

[0071] Figure 1 This is a schematic diagram of the construction process of the present invention;

[0072] Figure 2 This is a road spectrum data table for the design of irregular pebble-inlaid roads according to the present invention;

[0073] Figure 3 This is a comparison table of elevation control network data after back-calculation of the irregular pebble-paved road of the present invention;

[0074] Figure 4 This is a schematic diagram of the elevation controller of the present invention;

[0075] Figure 5 This is a schematic diagram of the elevation control network of the present invention. Detailed Implementation

[0076] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0077] Please see Figures 1-5 The present invention provides a method for constructing an irregular pebble-embedded concrete pavement for an automotive proving ground, comprising the following steps:

[0078] Construction preparation includes data preparation, tool preparation, material preparation, and base layer preparation;

[0079] Data preparation includes the following steps:

[0080] The irregular pebble-embedded concrete pavement is divided into a commercial vehicle test road and a passenger vehicle test road: the commercial vehicle test road is 580m long and 3.8m wide, with 19,000-20,000 elevation control points; the passenger vehicle test road is 760m long and 3.8m wide, with 25,000-26,000 elevation control points.

[0081] Extract the design road spectrum data table: Based on the design road spectrum, extract the elevation back-calculation data corresponding to the intersection points of the longitudinal 0.4m and the transverse 0.17m, 0.40m, 0.53m, 0.40m, 0.50m, 0.40m, 0.43m, 0.40m, 0.40m, and 0.27m, and assign them as row numbers. Define the top elevation of the curbstone as 0, positive values ​​as the elevation control point relatively higher than the curbstone + a, and negative values ​​as the elevation control point relatively lower than the curbstone - a.

[0082] Road Spectrum Elevation Difference Data Table Compilation: Based on the relative elevation difference H between the elevation controller benchmark beam and the curbstone, and combined with the design road spectrum data table, the road spectrum elevation difference data table is compiled using the inverse elevation difference formula, where the inverse elevation difference formula is: Δh=Hh;

[0083] H represents the relative height difference between the reference beam and the curb stones on both sides;

[0084] h represents the design road spectrum elevation control data;

[0085] Δh represents the inversely calculated elevation difference data;

[0086] The tool prepared in the tool preparation section is an elevation controller;

[0087] The elevation controller includes a stabilizing main frame, a stabilizing reference plate, a reference beam, and an elevation adjusting screw. The elevation controller has a "gate" structure.

[0088] The stabilizing reference plate and the stabilizing main frame are fixedly connected by welding, and the reference beam is connected to the stabilizing main frame by bolts. The reference beam is made of stainless steel and its length is consistent with the road width. The reference beam is engraved with scales that are consistent with the design transverse elevation control spacing. The error between the scales on the reference beam is less than 1mm. The bolts are used to adjust the distance between the reference beam and the stabilizing main frame to ensure that the reference beam and the top surface of the curb stones on both sides are in the same parallel state.

[0089] Material preparation includes the following steps:

[0090] Pebble Classification: Based on the pebble parameters required in the road design specifications, the pebble raw materials are classified into three categories: A, B, and C. Specific pebble parameters are shown in the table below.

[0091] Serial Number pebble type Pebble weight (commercial road) Weight of pebbles (passenger transport) Remark 1 A 2.5-3.5 0.5-1.0 Smooth river stones 2 B 3.5-4.5 1.0-2.0 Smooth river stones 3 C 4.5-5.5 2.0-3.0 Smooth river stones

[0092] Pebble preparation: Weigh and classify the raw pebble materials using an electronic scale with an accuracy of 0.2 kg. After classification, rinse the raw pebble materials with a water truck. After rinsing, the surface of the raw pebble materials must not have any impurities that affect the quality.

[0093] The specific steps for grassroots preparation are as follows:

[0094] Use tools to clean the concrete base of the irregular pebble-embedded road. Manually use a handheld gasoline blower to clean the formed concrete base. Before construction, the concrete base must not have sand, gravel, mortar, or garbage and waste soil. After the concrete base is completely cleaned, sprinkle water to moisten it.

[0095] Measurement and Setting Out: The specific steps for measurement and setting out are as follows:

[0096] Using a total station, the road curbstone is marked out at 20-meter intervals starting from the starting point, with an error of less than 2mm. Within the 20-meter intervals, points are marked at 40cm intervals longitudinally, and the points are numbered n1, n2, n3, etc., with an error of less than 1mm. The point numbers correspond to the row numbers in the elevation back-calculation data table to avoid the phenomenon of reading the wrong row and causing errors in the elevation control points of irregular road surfaces during later data use.

[0097] Reinforcing mesh installation: The reinforcing mesh installation includes the following steps:

[0098] The steel mesh is pre-processed and produced at the steel processing plant according to the design requirements of the construction drawings, and then transported to the site for installation.

[0099] At the construction site, an engineering chalk line is used to accurately mark a 5m*3.8m grid on the concrete base according to the irregular pebble inlay road reinforcement diagram. Markers and steel tape measures are used to mark the spacing points of the reinforcement. The reinforcement is tied with double wires and twisted securely. The excess wire ends extend into the inside of the reinforcement but must not extend into the net protective layer. The horizontal spacing of the reinforcement mesh is 0.2m and the vertical spacing is 0.15m. The reinforcement mesh is a single-layer structure with a reinforcement protective layer thickness of 4-6cm.

[0100] In the longitudinal steel mesh, a dowel bar is installed every 5m and 5m apart. The length of the dowel bar is 0.7m and the dowel bar is a plain round steel bar with a diameter of 25mm.

[0101] After the first layer of reinforcing bars is tied, place spacers on the first layer of reinforcing bars. After the reinforcing bars are tied, check and inspect the spacing of the reinforcing bars and adjust any reinforcing bars that do not meet the design and specification requirements.

[0102] Check whether the thickness of the concrete cover at the bottom of the reinforcing bars and the side formwork meets the design requirements. If it does not meet the design requirements, adjust the non-compliant parts to avoid corrosion of the reinforcing bars due to insufficient concrete cover thickness.

[0103] Establishment of elevation control points: The establishment of elevation control points includes the following steps:

[0104] Drilling for determining elevation control points: Based on the design road map data, mark and drill holes at the construction site according to the standard line marked by the chalk line;

[0105] Elevation control pile installation: Insert 8mm diameter threaded steel bars into the drilled holes. Before inserting the steel bars, inject steel bar fixing adhesive into the holes, and then use a small hammer to vertically hammer the steel bars. The depth of the steel bar holes is 110cm and the steel bars are exposed 23cm.

[0106] After the elevation control stakes are installed, the reverse elevation difference value is marked next to each elevation control stake, based on the back-calculated road spectrum elevation difference data table.

[0107] A 10cm-20cm long PVC sleeve is fitted over each steel bar to meet the design road profile requirements. A customized elevation controller is used to adjust the top elevation of the PVC sleeve according to the values ​​marked next to the elevation control stake in advance. The top elevation of the PVC sleeve is the road design elevation. The adjustment error of the road design elevation is controlled within ±1mm. After the road design elevation is properly adjusted, the 8mm diameter steel bar is wrapped and fixed to the PVC sleeve with tape.

[0108] Pouring concrete: Pouring concrete includes the following steps:

[0109] Pouring concrete:

[0110] The road surface layer is poured using a concrete compartmentalized pouring device. The concrete is C35 freeze-thaw resistant concrete with a flexural strength of HF-4.5. The concrete is poured continuously. When pouring the concrete into the formwork, avoid concentrated dumping that impacts the elevation control piles. To reduce the impact force of the concrete and cause errors in the top elevation of the elevation control piles, which would affect the elevation qualification rate after the road surface is formed, the concrete compartmentalized pouring device is used. This allows for adjustment of the pouring area, reduces the downward potential energy of the concrete, and ensures the qualification rate of the top elevation of the elevation control piles.

[0111] The concrete slab is poured continuously using a dowel bar positioner to ensure continuous concrete pouring. After pouring, a end plate is added, with pre-drilled holes located in the middle of the wooden formwork and spaced 60cm apart. Dowel bars are inserted into the end plate, with the insertion length of the dowel bars being half the length of the dowel bar.

[0112] Concrete slabs are poured continuously. If an interval is required during the pouring process, the interval should be shortened to before the initial setting of the previous concrete. The maximum interval for pouring concrete slabs is determined based on the type of cement used, the temperature, and the concrete setting conditions. If the interval for pouring concrete slabs exceeds 1 hour, it should be treated as a construction joint. When the surface of the poured concrete slab is no longer sticky to the touch, the surface of the concrete slab should be roughened.

[0113] When pouring concrete slabs, observe whether the formwork, reinforcing bars, and reserved holes have moved, deformed, or blocked. If any of the above situations are found, they need to be dealt with immediately and repaired before the poured concrete slabs have initially set.

[0114] When the concrete pouring is almost complete, estimate the remaining volume of concrete and contact the commercial concrete batching plant for reasonable scheduling to avoid construction waste;

[0115] Concrete vibration:

[0116] Concrete vibration should follow the principle of quick insertion and slow withdrawal. The insertion points of the vibrator should be evenly arranged in a quincunx pattern, and the vibrator should be moved point by point in sequence to ensure uniform compaction. The vibration movement distance should be less than 1.5 times the vibration radius, and the vibration movement distance should be 30-40cm. The vibration duration should be until the concrete surface produces laitance, no air bubbles, and no settling.

[0117] Pebble setting: Pebble setting includes the following steps:

[0118] Location of the pebble:

[0119] Based on the summary of multiple test block constructions, the optimal time for cobblestone embedding is 30-45 minutes after concrete pouring. The cobblestones are then manually embedded to the top of the corresponding elevation control piles according to the cobblestone road map requirements.

[0120] The pebbles were laid out according to the road layout design;

[0121] Pebble Inlay:

[0122] According to the pebble road pattern requirements, the pebbles are embedded in the designed positions. The form of the pebbles is randomly determined during the embedding process to avoid the same placement of pebbles in the area, which would affect the test results.

[0123] The gravel should be buried at a depth of 2 / 3 of its diameter, with the larger end facing down and the smaller end facing up.

[0124] Concrete pavement shaping: The shaping process is carried out manually, in three stages.

[0125] After the first pour of concrete on the irregular concrete road surface, the concrete is shaped. During the first shaping, the elevation difference of the set elevation control piles is connected in an arc shape to ensure that the concrete surfaces of every two elevation control piles are connected smoothly.

[0126] The second shaping and finishing process is carried out after the pebbles are inlaid. The shape of the first shaping is used as a reference to refine the concrete pavement after the pebbles are inlaid.

[0127] The third shaping is performed before the concrete sets. This third shaping ensures a tight connection between the concrete and the pebbles at the joints after the concrete collapses, guaranteeing a strong bond between the concrete and the pebbles.

[0128] Construction joint installation: Construction joint installation includes the following steps:

[0129] Contraction joints: After the concrete pavement has set, joints can be cut. One contraction joint should be set every 5m of concrete pavement. The width of the joint should be 4-6mm and the depth of the contraction joint should be greater than 1 / 3 of the thickness of the poured slab. A dowel bar with a diameter of 25mm should be set at the contraction joint. The length of the dowel bar should be 45-55cm and the spacing between the dowel bars should be 55-65cm. One end of the dowel bar should be coated with asphalt and wrapped with polyethylene film.

[0130] Expansion joints: One expansion joint is set every 200m of concrete pavement. The expansion joint is filled with 2cm joint filler board. The dowel bar is installed in the same way as the contraction joint above. The joint is filled to a depth of 30-40mm.

[0131] When contraction joints, expansion joints, and pebbles conflict, adjust the position of the expansion joints and contraction joints;

[0132] Road surface maintenance: The specific steps for road surface maintenance are as follows:

[0133] After the irregular pebble-embedded pavement has been poured and embedded, it will be covered with water-retaining geotextile for curing. The number of times the pavement is sprayed with water during the curing period depends on the natural temperature of the day, and the surface should always be kept moist. The curing time is more than 7 days.

[0134] Crack filling: Crack filling includes the following steps:

[0135] Remove the extruded polystyrene board and clear away debris. Use silicone sealant to install standard basalt bricks, ensuring the shrinkage and elevation requirements between adjacent boards.

[0136] Silicone sealant was used to fill the expansion joints and gaps between adjacent concrete slabs. Before filling the joints, the debris inside the joints must be cleaned, the sponge strips must be filled tightly, and the filling depth must be consistent with the original cutting depth of the expansion joints.

[0137] This invention, through reasonable optimization of construction techniques, achieves high-quality construction, fast construction speed, and ensures project progress. The irregular cobblestone inlaid road is 1340m long, and the special pavement layer construction was completed within an effective construction period of 100.5 days. In contrast, the traditional construction process, which uses manual drilling and rebar installation, has an effective construction period of 134 days. This invention saves construction time, improves the accuracy of pavement elevation control and the quality of the finished road, increases labor efficiency, saves human resources, and reduces costs. The new process achieves a one-time forming rate for irregular cobblestone inlaid concrete pavement, ensuring the quality of pavement formation and providing a reference for similar road construction.

[0138] Table 1 below is a comparison table of the construction method of this invention and the traditional construction method. This comparison table uses a construction section of 1.34 km in length as the comparison for both construction methods:

[0139] Table 1

[0140]

[0141] Construction period using traditional methods: The cobblestone road is 1.34km long. Assuming an 8-hour workday, the time required to construct 10m of cobblestone road using traditional methods is shown in Table 2 below.

[0142] Table 2

[0143]

[0144] Using conventional construction methods, it takes 8 hours to construct 10 meters of cobblestone road, and 134 days to complete 1.34 km.

[0145] Construction period of the construction method of this invention: The length of the cobblestone road is 1.34km, and the daily working time is calculated as 8 hours. The time required to construct 10m of cobblestone road using the construction method of this invention is shown in Table 3 below:

[0146] Table 3

[0147]

[0148] Using the construction method of this invention, it takes 6 hours to construct 10m of cobblestone road, and 100.5 days to complete 1.34km.

[0149] Table 4 below compares the specific construction personnel costs required to construct 20 meters using traditional construction methods and the construction method of this invention.

[0150] Table 4

[0151]

[0152] The main equipment used in the construction of this irregular pebble-embedded concrete pavement is a 50mm vibrator and a concrete mixer truck. The traditional construction method requires 16.75 days for vibration and pouring, while the construction method of this invention reduces the vibration and pouring time to 12.56 days, improving construction efficiency by 25%.

[0153] The following two construction projects represent two implementation scenarios for this construction method:

[0154] The irregular cobblestone pavement in a certain test site project is located on the T13 fatigue durability road. The commercial vehicle test road is 580 meters long and 3.8 meters wide, with a total of 19,160 elevation control points; the passenger vehicle road is 760 meters long and 3.8 meters wide, with 25,160 elevation control points and a cross slope of 1%. The pavement material is mainly composed of C35 freeze-thaw resistant concrete and cobblestones. The construction period of this road was from June 2018 to November 2018.

[0155] The above-mentioned test site project adopted the construction method of this invention for road construction, which solved the problem of difficulty in controlling the elevation of irregular cobblestone inlaid concrete pavement and irregular cobblestone inlay, improved the pass rate of various control indicators of irregular cobblestone inlaid road, solved the problems of difficult construction, high rework rate, high construction cost and low machinery utilization, improved construction progress and construction quality, and achieved good economic and social benefits.

[0156] The irregular pebble-paved road in a certain test site project is 1450 meters long and 3.8 meters wide, with a total of 53,642 elevation control points. The road surface material is mainly composed of C35 freeze-thaw resistant concrete and pebbles. The construction period of this road is from April 2017 to September 2017.

[0157] The above-mentioned test site project adopted the construction method of this invention for road construction. The construction process of reverse calculation of elevation using an inverted ruler is simple, fast and accurate, effectively saving manpower, shortening the construction period, and facilitating construction production organization. By controlling the initial setting node of concrete before irregular cobblestone inlay, the elevation, firmness, finished road surface and appearance quality of the irregular cobblestones are guaranteed.

[0158] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for constructing an irregular pebble-embedded concrete pavement at an automotive proving ground, characterized in that, Includes the following steps: Construction preparation: The construction preparation includes data preparation, tool preparation, material preparation and base preparation; Surveying and setting out: Use a total station to mark out the road markings at equal intervals on the curb; Steel mesh installation: Steel mesh is installed on the concrete base according to the design requirements of the construction drawings; Elevation control point layout: The elevation control point layout includes drilling for elevation control point determination and installation of elevation control piles; Concrete pouring: The concrete pouring includes concrete pouring and concrete vibration; Pebble inlay: The pebble inlay includes pebble positioning, pebble embedding depth, and concrete pavement shaping; Construction joint layout: The construction joint layout includes contraction joints and expansion joints; Road surface curing: Use water-retaining geotextile to cover and cure irregular cobblestone inlaid road surfaces; Crack filling: Use silicone sealant to fill expansion joints and gaps between adjacent concrete slabs; The material preparation includes the following steps: Pebble classification: Based on the pebble parameters required in the road design specifications, the pebble raw materials are classified into three categories: A, B, and C. Pebble preparation: Weigh and classify the raw pebble materials using an electronic scale with an accuracy of 0.2 kg. After classification, rinse the raw pebble materials with a water truck. After rinsing, the surface of the raw pebble materials must not have any impurities that affect the quality. The specific steps for locating the pebble are as follows: Based on the summary of multiple test block constructions, the optimal time for cobblestone embedding is 30-45 minutes after concrete pouring. The cobblestones are then manually embedded to the top of the corresponding elevation control piles according to the cobblestone road map requirements. The pebbles were laid out according to the road layout design; The specific steps for embedding the pebbles at the specified depth are as follows: According to the pebble path requirements, the pebbles are inlaid in the designed positions, and the form of the pebbles is randomly determined during the inlaying process; The gravel should be buried at a depth of 2 / 3 of its diameter, with the larger end facing down and the smaller end facing up. The specific steps for shaping the concrete pavement are as follows: The shaping process is carried out manually, in three stages. After the first pour of concrete on the irregular concrete road surface, the concrete is shaped. During the first shaping, the elevation difference of the set elevation control piles is connected in an arc shape to ensure that the concrete surfaces of every two elevation control piles are connected smoothly. The second shaping and finishing process is carried out after the pebbles are inlaid. The shape of the first shaping is used as a reference to refine the concrete pavement after the pebbles are inlaid. The third shaping is performed before the concrete sets. This third shaping ensures a tight connection between the concrete and the pebbles at the joints after the concrete collapses, guaranteeing a strong bond between the concrete and the pebbles. The specific steps for road surface maintenance are as follows: After the irregular pebble-embedded pavement has been poured and embedded, it will be covered with water-retaining geotextile for curing. The number of times the pavement is sprayed with water during the curing period depends on the natural temperature of the day, and the surface should always be kept moist. The curing time is more than 7 days. The crack sealing process includes the following steps: Remove the extruded polystyrene board and clear away debris. Use silicone sealant to install standard basalt bricks, ensuring the shrinkage and elevation requirements between adjacent boards. Expansion joints and gaps between adjacent concrete slabs are filled with silicone sealant. Before filling, debris inside the joints must be cleaned, and the sponge strips should be filled tightly. The filling depth should be consistent with the original depth of the expansion joint.

2. The construction method for an irregular pebble-embedded concrete pavement in an automotive proving ground according to claim 1, characterized in that: The data preparation includes the following steps: The irregular pebble-embedded concrete pavement is divided into a commercial vehicle test road and a passenger vehicle test road: the commercial vehicle test road is 580m long and 3.8m wide, with 19,000-20,000 elevation control points; the passenger vehicle test road is 760m long and 3.8m wide, with 25,000-26,000 elevation control points. Extract the design road spectrum data table: Based on the design road spectrum, extract the elevation back-calculation data corresponding to the intersection points of the longitudinal 0.4m and the transverse 0.17m, 0.40m, 0.53m, 0.40m, 0.50m, 0.40m, 0.43m, 0.40m, 0.40m, and 0.27m, and assign them as row numbers. Define the top elevation of the curbstone as 0, positive values ​​as the elevation control point relatively higher than the curbstone + a, and negative values ​​as the elevation control point relatively lower than the curbstone - a. Road Spectrum Elevation Difference Data Table Compilation: Based on the relative elevation difference H between the elevation controller benchmark beam and the curbstone, and combined with the design road spectrum data table, the road spectrum elevation difference data table is compiled using the inverse elevation difference formula, where the inverse elevation difference formula is: △h=Hh; H represents the relative height difference between the reference beam and the curb stones on both sides; h represents the design road spectrum elevation control data; △h represents the inversely calculated elevation difference data; The tool prepared in the tool preparation is an elevation controller; The elevation controller includes a stabilizing main frame, a stabilizing reference plate, a reference beam, and an elevation adjusting screw. The elevation controller has a "gate" structure. The stabilizing reference plate is fixedly connected to the stabilizing main frame by welding, and the reference beam is connected to the stabilizing main frame by bolts. The reference beam is made of stainless steel and its length is consistent with the road width. The reference beam is engraved with scales that are consistent with the design lateral elevation control spacing. The distance error between the scales on the reference beam is less than 1mm. The bolts are used to adjust the distance between the reference beam and the stabilizing main frame to ensure that the reference beam is parallel to the top surface of the curb stones on both sides. The specific steps for grassroots preparation are as follows: Use tools to clean the concrete base of the irregular pebble-embedded road. Manually use a handheld gasoline blower to clean the formed concrete base. Before construction, the concrete base must not have sand, gravel, mortar, or garbage and waste soil. After the concrete base is completely cleaned, sprinkle water to moisten it.

3. The construction method for an irregular pebble-embedded concrete pavement in an automotive proving ground according to claim 1, characterized in that: The specific steps for the measurement and layout are as follows: Using a total station, starting from the starting point, the road curb is marked with 10-meter intervals, with an error of less than 2mm. Within 20 meters, points are marked with longitudinal intervals of 40cm, and the points are numbered n1, n2, n3, etc., with an error of less than 1mm. The point numbers correspond to the row numbers in the elevation back-calculation data table.

4. The construction method for an irregular pebble-embedded concrete pavement in an automotive proving ground according to claim 1, characterized in that: The installation of the steel mesh includes the following steps: The steel mesh is pre-processed and produced at the steel processing plant according to the design requirements of the construction drawings, and then transported to the site for installation. At the construction site, an engineering ink marker was used to accurately mark a 5m*3.8m grid on the concrete base according to the irregular pebble inlay road reinforcement diagram. A marker pen and steel tape measure were used to mark the spacing points of the reinforcement. The reinforcement was tied with double wire and twisted securely, with the excess wire end extending into the inside of the reinforcement. The horizontal spacing of the reinforcement mesh was 0.2m and the vertical spacing was 0.15m. The reinforcement mesh was arranged as a single-layer structure, with a reinforcement protective layer thickness of 4-6cm. In the longitudinal steel mesh, a dowel bar is installed every 5m and 5m apart. The length of the dowel bar is 0.7m and the dowel bar is a plain round steel bar with a diameter of 25mm. After the first layer of reinforcing bars is tied, place spacers under the first layer of reinforcing bars. After the reinforcing bars are tied, check and inspect the spacing between the reinforcing bars. Check whether the thickness of the concrete cover at the bottom of the reinforcing bars and the side formwork meets the design requirements. If it does not meet the design requirements, adjust the non-compliant parts.

5. The construction method for an irregular pebble-embedded concrete pavement in an automotive proving ground according to claim 1, characterized in that: The specific steps for determining the elevation control points through drilling are as follows: Based on the design road map data, mark the drilling points at the construction site according to the standard lines marked by the ink line; The specific steps for installing the elevation control piles are as follows: insert 8mm diameter threaded steel bars into the drilled holes. Before inserting the steel bars, inject steel bar fixing adhesive into the holes, and then use a small hammer to vertically hammer the steel bars. The depth of the steel bar holes is 110cm and the steel bars are exposed 23cm. After the elevation control stakes are installed, the reverse elevation difference value is marked next to each elevation control stake, based on the back-calculated road spectrum elevation difference data table. A 10cm-20cm long PVC sleeve is fitted over each rebar to meet the design road profile requirements. A customized elevation controller is used to adjust the top elevation of the PVC sleeve according to the values ​​marked next to the elevation control stakes in advance. The top elevation of the PVC sleeve is the road design elevation. The adjustment error of the road design elevation is controlled within ±1mm. After the road design elevation is properly adjusted, the 8mm diameter rebar is wrapped tightly and fixed to the PVC sleeve with tape.

6. The construction method for an irregular pebble-embedded concrete pavement in an automotive proving ground according to claim 1, characterized in that: The specific steps for concrete pouring are as follows: The road surface layer is poured using a concrete compartmentalized pouring device. The concrete is C35 freeze-thaw resistant concrete with a flexural strength of HF-4.

5. The concrete is poured continuously to avoid concentrated dumping that could impact the elevation control piles when it is poured into the formwork. The concrete slab is poured continuously using a dowel bar positioner to ensure continuous concrete pouring. After pouring, a end plate is added, with pre-drilled holes located in the middle of the wooden formwork and spaced 60cm apart. Dowel bars are inserted into the end plate, with the insertion length of the dowel bars being half the length of the dowel bar. Concrete slabs are poured continuously. If an interval is required during the pouring process, the interval should be shortened to before the initial setting of the previous concrete. The maximum interval for pouring concrete slabs is determined based on the type of cement used, the temperature, and the concrete setting conditions. If the interval for pouring concrete slabs exceeds 1 hour, it should be treated as a construction joint. When the surface of the poured concrete slab is no longer sticky to the touch, the surface of the concrete slab should be roughened. When pouring concrete slabs, observe whether the formwork, reinforcing bars, and reserved holes have moved, deformed, or blocked. If any of the above situations are found, they need to be dealt with immediately and repaired before the poured concrete slabs have initially set. When the concrete pouring is almost complete, estimate the remaining volume of concrete and contact the commercial concrete batching plant for reasonable scheduling. The specific steps for concrete vibration are as follows: Concrete vibration should follow the principle of quick insertion and slow withdrawal. The insertion points of the vibrator should be evenly arranged in a quincunx pattern, and the vibrator should be moved point by point in sequence to ensure uniform compaction. The vibration movement distance should be less than 1.5 times the vibration radius, and the vibration movement distance should be 30-40cm. The vibration duration should be until the concrete surface produces laitance, no air bubbles, and no settling.

7. The construction method for an irregular pebble-embedded concrete pavement in an automotive proving ground according to claim 1, characterized in that: The specific steps for the contraction joint are as follows: After the concrete pavement has set, joints can be cut. One contraction joint should be set every 5m of concrete pavement. The width of the joint should be 4-6mm and the depth of the contraction joint should be greater than 1 / 3 of the thickness of the poured slab. A dowel bar with a diameter of 25mm should be set at the contraction joint. The length of the dowel bar should be 45-55cm and the spacing between the dowel bars should be 55-65cm. One end of the dowel bar should be coated with asphalt and wrapped with polyethylene film. The specific steps for the expansion joint are as follows: one expansion joint is set every 200m of concrete pavement. The expansion joint uses a 2cm joint filler board. The dowel bar is installed in the same way as the contraction joint steps described above. The joint is filled to a depth of 30-40mm. When contraction joints, expansion joints, and pebbles conflict, adjust the position of the expansion joints and contraction joints.

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