Main construction methods (1). Before laying 1 sidewalk blocks and lofting sidewalk pavement, according to the designed plane and elevation, measure the setting-out along the center line (or sideline) of the sidewalk, measure a brick every 5m~ 10m as the control point, and establish a grid to control the elevation and direction. 2. Cushion shall be constructed according to the location and elevation of survey lofting. The pavement cushion adopts C 15 cm thick non-pumped commercial concrete cushion. 3. Paving (1) generally adopts the sequence of "setting out and positioning", and colored bricks should be close to the cushion layer, and there should be no "void" phenomenon. (2) often use a three-meter ruler to measure the flatness of the surface along the longitudinal, transverse and oblique directions. If it is found that it does not meet the requirements, it will be repaired in time. (3) Paving must be smooth and stable, with straight vertical and horizontal joints, neat rows and even gaps. 4. After the completion of joint filling and curing paving, joint filling can be carried out only after passing the inspection. Mix the sieved dry sand with cement and evenly fill the brick joints, sprinkle water on the brick surface to make the sand ash sink, and tick off the joints with cement mortar that meets the design requirements. The jointing must be completely hooked and pressed into the concave joint on the surface; After the mortar is solidified, it can only be used by sprinkling water for 7 days. (2) cement concrete pavement construction 1, before the construction lofting, according to the design requirements, the temporary pile points set during the construction of water-stable layer are used for measuring lofting, and the plate positions are determined and well divided, and positioning control is carried out. Control piles are set at each corner of the roadway for inspection and retest at any time. 2. Formwork shall be supported according to the vertical and horizontal elevation of concrete slab. Formwork shall be supported by corresponding high steel formwork. Because the formwork is supported on the cement stabilized macadam layer, the aperture and depth should be slightly smaller than the supporting steel bar and supporting depth for convenient operation. Before formwork support, the steel formwork shall be drilled and numbered according to the setting requirements of dowel bars and pull rods designed for longitudinal and transverse joints, and formwork support shall be carried out in strict order. The position of the hole is slightly larger than the diameter of the designed dowel bar and pull rod. In order to avoid slurry leakage, elevation measurement should be carried out after formwork is supported to check whether it is firm, and release agent should be brushed before pouring cement concrete. 3, concrete mixing, transportation concrete using centralized mixing concrete, by our company in advance in accordance with the design requirements for trial mixing, mixing in strict accordance with the requirements of accurate materials provided by the laboratory. Concrete is transported by concrete truck. 4. Steel bars are made. After steel bars are processed and made, they are put to the site in a unified way according to the design requirements, and put outside before cement concrete pouring. 5. 1 The steel bars at the edge of the free plate should be placed at the edge of the free plate, not less than 5cm away from the edge of the plate, supported by precast concrete pads, with the pad thickness of 4cm, the pad spacing not more than 80cm, and the spacing between two steel bars not less than 10cm. In the process of pouring concrete, the middle of the steel bar should be straight, without deformation and deflection, and prevent displacement. 5.2 Corner steel bars shall be placed when the concrete is poured and vibrated to a difference of 5cm from the design thickness, with a distance of 10cm from expansion joints and slab edges, and the pouring and vibrating shall be continued after the upper concrete is laid in place. 5.3 The anti-crack reinforcement of inspection wells and rain outlets shall be placed in the same way as the reinforcement on the edge of the free plate. 6, concrete paving, vibrating steel bar in place after concrete paving, besmear brushs release agent before paving, in order to protect the steel bar from moving or dislocation. That is, after the concrete is spread to half thickness, it will be vibrated with a flat vibrator first, and then with a flat vibrator after preliminary leveling. When vibrating, the vibrator moves from the roadside to the pavement line by line in the longitudinal direction, and the overlapping surface before and after each plate movement is about 20cm (about 1/3 plate width), so as not to leak vibration. The vibration time of the vibrator at each position is generally 15s-25s, which should not be too long until the concrete mixture is submerged and the surface is uniform without obvious lumps or blisters. In places that cannot be vibrated, such as the edge of the formwork and near the water inlet, plug-in vibrators should be used for vibration. When vibrating, the vibrator should twitch vertically and slowly, and the distance between each movement should not be greater than 1.5 times the action radius. The spacing between the plug-in vibrator and the template is generally about 10cm. The plug-in vibrator does not vibrate on the dowel bar, so as not to damage the concrete at the edge of adjacent plates. The concrete surface leveled by flat vibrator is basically flat, and there is no obvious concave-convex trace. Then use vibration tamping template to tamp and level. When vibrating, put both ends of the vibrating rod template on the longitudinal templates on both sides, or on the poured cement slabs on both sides as the basis for controlling the pavement elevation. Vibrate twice from one end to the other. 7. After plastering and embossing the concrete slab, use a trowel to smooth the concrete surface, and then manually dry the concrete surface. For the last time, it is required to be meticulous, eliminate sand holes, and make the concrete slab meet the flatness requirements. After polishing, brush lightly along the cross slope with a combination brush to flatten the traces, and then emboss the concrete surface with an embossing machine. In order to ensure the uniform indentation depth and control the embossing operation time, angle iron is used as a guide during embossing. During construction, the straightness of the guide rule should be checked frequently, and the deviation should be replaced in time. 8. Be careful when tearing. Don't knock with a sledgehammer to avoid damaging the corners. The formwork removal time should be within 36~48 hours after the final setting of concrete, so as to avoid premature formwork removal and damage to concrete corners. 9. Expansion joint expansion joint plate is made of 2cm thick asphalt plate, coated with 1-2mm asphalt on both sides, and buried in the road surface, and the height of the plate is consistent with the height of the road surface. Before filling asphalt mortar, cut 4-5cm from its upper part, and then fill asphalt mortar. 10, joints and contraction joints are cut by concrete cutting machine, with a depth of 5cm and a slice thickness of 3mm, and the cutting shall be carried out after formwork removal. When the formwork is removed, the position of the contraction joint has been marked on the cement concrete block. If the transverse contraction joint position (without dowel bar) is located at the inspection well and the rain mouth, the contraction joint position should be readjusted, and in principle, it should be controlled at a distance of more than 1.2m from the well position. Line drawing is required before cutting, and the line drawing should be aligned with the cutting line to ensure that the horizontal joints at the same pile position are straight and beautiful, and the depth is even when cutting. 1 1, asphalt mortar should be poured into the joint to expand with heat and contract with cold. Dust and sundries in the joint should be removed before pouring, and pouring should be carried out after the joint is completely dry. 12. Maintenance: After the final setting of road concrete, cover the straw bag and spray water for maintenance. During the maintenance period, no heavy objects will be piled up, and pedestrians and vehicles will not pass on the concrete pavement. (III) Materials for asphalt concrete pavement construction 1 and construction preparation (1) Commercial asphalt concrete is used in this project. (2) Asphalt prime coat In the pavement construction of this project, it is considered to spread prime coat asphalt between asphalt concrete and between asphalt concrete and gravel layer. Before construction, grass-roots units should thoroughly check it again and strictly control it to prevent potential quality hazards. Use asphalt distributor to automatically spread asphalt with the dosage of 0.8- 1KG/M2, immediately spread 3-8MM aggregate with the dosage of 1 M3/ 1000 M2, and roll it with 6-8t steel roller 1-2 times. In specific construction, first make a test road and wait for construction. The running speed of distributor, the height and angle of nozzle are determined by experiments and reported to the supervision engineer for approval. During the construction, it is necessary to prevent asphalt from polluting the structure, pay attention to protecting the side slabs and sidewalk boards, so as not to affect the beauty of the road, and minimize traffic after sealing construction. (3) Before the asphalt pavement in the test section is formally constructed, select a suitable section as the test road. The construction of the test road is divided into two stages: trial mixing and trial paving. The test content mainly includes the following aspects: a. According to the matching principle of various construction machinery on asphalt pavement, determine the reasonable construction machinery, the number of machinery and the combination mode. B, determining the paving temperature, paving speed, paving width and automatic leveling mode of the paver through trial paving; Determine the compaction sequence, compaction temperature, compaction speed and compaction times of the roller; Determine loose laying coefficient, joint method, etc. C. Verify the design result of asphalt mixture ratio, and put forward the mineral mixture ratio and asphalt consumption for production. D, establish the comparative relationship between the drilling method and the nuclear densitometer method to determine the density. Determine the compaction standard density of various internal asphalt concrete. E. determine the construction output and the length of the operation section, and make the construction plan. F. comprehensively check the quality of materials and construction. G determine the construction organization and management system, personnel, communication and command mode. In the process of paving the test section, carefully record and analyze, take the initiative to accept the supervision of the supervision engineer or the engineering quality supervision department, check the construction quality of the test section, and judge the relevant results. After paving, put forward the test summary report of each test content in time and submit it to the supervision engineer for approval as the construction basis. 2, transportation and paving A. The arrangement of transportation vehicles should ensure the traffic flow of the asphalt mixing station for one hour, and at the same time ensure that there are always vehicles waiting in line for unloading in front of the paver. The floor and side plates of the trunk of vehicles transporting asphalt mixture must be clean and free of organic substances. In order to prevent the mixture from sticking to the trunk floor, a thin layer of oil-water (diesel water is 1:3) mixture can be coated. In order to keep the temperature of asphalt mixture and prevent the mixture from being polluted by dust, the truck should be covered with tarpaulin and transported by a large dump truck, and the temperature of asphalt mixture transported to the site should not be lower than 135℃. Mixtures that do not meet the temperature requirements or are caked and wet by rain should be discarded. B. Before paving asphalt pavement, the pavement base must be checked again to eliminate quality hidden dangers before the next working procedure can be carried out. Usually, the contents to be checked include whether the asphalt seal on the surface of the base is damaged, whether the flatness, cross slope, width and elevation meet the requirements, and at the same time, the surface of the structure contacted by the asphalt mixture is coated with sticky asphalt. Before paving, engineers and technicians should first release the construction layout and set the leveling datum line. One pile shall be set every 10m for straight line section and every 5m for flat curve section. The special pile for hanging line should be placed at 0.3~0.5m from the road edge on both sides, and the hanging line height should be loose height. Make the upper and lower standard cushion blocks respectively (design thickness+loose laying thickness). Through the successful experience of paving in the experimental section, the data such as paving speed, vibration frequency, loose paving coefficient, rolling speed, rolling times and minimum rolling temperature of pavement are determined. In order to improve the smoothness of the pavement, the paving speed should match the material entry speed, so as to ensure the continuous paving of the paver in an operation section, and the asphalt concrete entry plan should be arranged reasonably during the construction process to prevent the loss caused by excessive cooling of the asphalt mixture. The lower layer is paved with steel wire to take the datum line to control the elevation, flatness and transverse slope, and the upper layer is paved with floating datum beam to ensure the paving thickness and smoothness. Before paving, the paver should be in place 30 minutes in advance, and the screed should be preheated to 120℃ before paving. The paving temperature of asphalt mixture should not be lower than 130℃. Usually, two pavers are used to form an echelon for joint paving. The spacing between two pavers is generally 10-30m, and the tracks of the two pavers overlap by 50 ~ 100. When paving the whole width with a paver, a trial paving must be carried out, and the segregation degree of the mixture must be guaranteed not to affect the quality of asphalt pavement, and it can only be adopted with the consent of the supervision engineer. During paving, it is not allowed to change the speed or stop halfway at will. After paving, it is not allowed to trim the mixture repeatedly by hand, except for the following situations: △ The cross section is not up to the requirements △ There is a local shortage of materials at the joint of the structure △ There is a local shortage of materials at the edge of the paving belt △ The surface is obviously uneven △ The local mixture is obviously separated △ There are obvious drag marks after the paver. The paved asphalt mixture shall be rolled immediately. If it cannot be rolled in time for any reason or in case of rain, the rolling should be stopped immediately and the asphalt mixture should be insulated. After the lower pavement paving is completed, the upper pavement paving should be arranged as soon as possible. If the interval is long and the surface of the lower layer is polluted, the surface of the lower layer should be cleaned before paving the upper layer, and an appropriate amount of prime asphalt should be sprinkled as appropriate. C. The rolling operation shall be carried out at the temperature where the mixture can obtain the maximum compactness. Generally, the initial rolling temperature is not lower than 120℃, and the final rolling temperature is not lower than 70℃ for steel wheel roller, 80℃ for tire roller and 65℃ for vibratory roller. The compaction work shall be carried out according to the combination and procedure of compaction equipment determined by paving the test pavement. The general rolling process is divided into three stages: primary rolling, secondary rolling and final rolling. Because the uranium paver used in this project has double rammers and mechanical vibration devices, and the vibration frequency can be adjusted according to the type of mixture and paving thickness, the pre-compaction degree of paving pavement can reach more than 80%. Therefore, the compaction method we adopt is to follow the paver with a road roller for static rolling for L times, then with a heavy tire roller for 4-6 times, and then with a vibratory roller for vibration rolling for L times and static rolling for 1-2 times to eliminate wheel tracks. Compaction should be carried out from the outside to the center of the road surface, with adjacent rolling belts overlapping a certain wheel width. The road surface where the roller travels back and forth should be straight, and the position of turning back from both ends is trapezoidal every time, and it will be pushed forward with the paver, so that the turning back place is not on the same cross section. The tire pressure of the tire roller should be consistent (not less than 0.5MPa) to prevent uneven tire hardness and smoothness. When the pavement temperature drops below 70℃, it can't be rolled again. The rolling speed is kept slow and uniform, with the general initial rolling speed of 1.5-2km/h, recompression speed of vibration roller of 4-5km/h, tire roller of 3.5-4.5km/h and final rolling speed of 2-3 km/h. When the paver is spreading continuously, the roller shall not be stopped at will. In other places along kerbs or where rollers cannot reach, the mixture should be fully compacted with a small compactor. Rolled pavement shall not be repaired. The rolling method of asphalt pavement is not static, because the compaction quality is directly related to the compaction temperature, and the temperature of the mixture after paving is constantly changing, especially within 4- 15 minutes after paving, the temperature loss is the largest, so it is necessary to master the effective compaction time, roll in time, and adjust the rolling method in time according to the paving thickness and natural conditions to ensure the compaction quality. D. The quality of joint transverse joint treatment directly affects the smoothness and driving comfort of asphalt pavement. When paving, the transverse joints should be located at the joints of the structure as far as possible. If it is unavoidable, at the end of the construction, the paver will lift the screed slightly about L meters away from the site before approaching the end, manually shovel the mixture at the end and then roll it, then check the flatness with a three-meter ruler, and vertically remove the part with insufficient thickness at the end before cooling, so that it can be connected at right angles in the next construction. Before re-paving, carefully check the end flatness with a three-meter ruler, and reject those that do not meet the requirements. After meeting the requirements, apply sticky asphalt on the vertical surface, adjust the reserved height when paving, and roll it in time after paving. Firstly, a roller is used for transverse rolling, and a slideway driven by the roller is placed outside the rolling belt. When rolling, the roller is located on the compacted mixture layer, and the width of the new rolling layer is 15cm. Then move 15-20cm to the freshly paved mixture every time, and then roll it longitudinally. After the joint construction is completed, check the flatness with a three-meter ruler. If it does not meet the requirements, it should be treated immediately when the mixture is not cooled to ensure the smoothness of the pavement at the transverse joints. In addition, it should be noted that the transverse joints of two adjacent floors or upper and lower floors should be staggered by more than L meters. E. quality control during paving, always pay attention to visual inspection, handle problems in time when found, and ensure that the surface is smooth and dense, the edges are neat, there are no phenomena such as flooding, looseness, cracks, edge gnawing, concentration of coarse and fine aggregates, no obvious wheel marks on the surface, the horizontal joints are tight and smooth, and the surface layer is connected smoothly with kerbs and other structures without water. (4), brick drainage ditch 1, construction preparation: ordinary bricks should be watered the day before laying, and it is not appropriate to water and spray bricks immediately, but should be used immediately. Pop up the wall of the ditch on the foundation cushion, and indicate the number of skins on the skin number line according to the ditch depth, brick specifications and mortar joint thickness required by the design. According to the elevation of the bottom brick on the skin number line, it can be checked by drawing or level gauge. When the horizontal mortar joint thickness of the first leather brick exceeds 20mm, it should be leveled with fine stone concrete first. It is strictly forbidden to mix broken bricks into masonry mortar or level it with mortar, and the method of filling the middle with bricks on both sides shall not be adopted. 2. Mixing mortar Mortar is mixed by the mortar mixing station set on site. Weigh the ingredients according to the mortar mixture ratio provided by the laboratory, and the accuracy of cement batching is controlled within 2%; The accuracy of sand and gravel batching is within 5%. Mortar should be mechanically stirred, and the feeding sequence is sand, cement and admixture before adding water. From the end of feeding, the mixing time shall not be less than 65438 0.5 minutes. Mortar should be used with mixing, and cement mortar and cement mixed mortar must be used within 3 hours and 4 hours after mixing respectively. 3. Before laying, the number of skins should be calculated according to the height of red brick and the thickness of mortar joint, and the number of skins should be set on both sides of the ditch. Red brick masonry should be watered before wetting. The horizontal mortar joint should be straight, the horizontal mortar joint thickness and vertical mortar joint width are generally 10mm, the minimum is 8mm, and the maximum is 12 mm ... The corner and junction of red brick should be built at the same time. If it cannot be built at the same time, the inclined IF should be retained. The length of the inclined fork should be equal to or greater than the height of the inclined fork. (5) The side flat stones of paving stones are actually composed of side stones and flat stones. Its function is to divide the boundary between roadway and sidewalk, and it is also an important facility for road drainage, and at the same time it plays a role in protecting the edge of pavement structure. Sidestone: it bears the lateral pressure of sidewalks, safety posts and green belts, and forms a pavement drainage ditch with the plane. The longitudinal slope of the side stone is generally parallel to the longitudinal slope of the road, and the top surface of the side stone is the edge of the sidewalk, which is higher than the top surface of the flat stone 12- 18 cm. Flat stone: determine the width of roadway, protect the edge of pavement surface structure, and form pavement drainage ditch together with kerbstone. 1, lofting (1) After checking that the road centerline is correct, measure the road boundary in turn, carry out sideline lofting, and determine the side piles. (2) According to the principle that the longitudinal slope of pavement design is parallel to the longitudinal slope of kerb, the top elevation of kerb is calculated and determined. (3) When the road is rebuilt, the side flat stone shall be laid at the site according to the requirements of the new row of masonry, and the elevation of the original rainwater outlet shall be adjusted to smoothly connect with the original side flat stone. 2. Trench tamping: excavate the foundation trench according to the design drawing, level and tamp the trench bottom, and pave the paving layer. 3. Paving gravel cushion and concrete foundation: (1) The construction width of subgrade shall include the width of side flat stone foundation, which shall be replaced by corresponding pavement materials. (2) The lower part of the bottom surface of concrete base shall be filled with suitable road-building materials, leveled and compacted. 4. Sidestone paving construction (1): Set out the construction line according to the plane position and top elevation of the side stone determined by the construction drawing. Generally, the kerb at the slope of the sidewalk is about 2-3 cm higher than the flat stone, and the joints at both ends should be made into a slope shape (commonly known as "bracket type"). (2) Joints of adjacent kerbs must be flush, and the joint width is 1CM. After inspection, they shall be butted in time. (3) Flat stone construction: Flat stones and kerbs should be staggered, centered and connected. The joint width between flat stones is 1CM, and the gap between flat stones and side stones is ≤ 1CM. (4) The connection between Shi Ping and the road surface must be straight. (5) the side flat stone is used for joint filling, and the compressive strength of cement mortar used for joint filling should be >: 10Mpa. Joint filling must be full and embedded, and jointing should be flat or concave. (6) Newly-built side flat stones should be protected by guardrails, and the joints should be wet-cured for not less than 3d, and anti-freezing should be paid attention to in winter. (7) Side flat stone paving shall be neat and firm, straight, with smooth fillet, full seam filling and smooth and firm hook (wipe) seam. (8) Pingshi drainage must be smooth, without water and water resistance. (9) The side flat stone dock shall be compacted tightly without looseness, and the side fill shall be compacted and paved, and the joint can be filled only after passing the inspection. Mix the sieved dry sand with cement and evenly fill the brick joints, sprinkle water on the brick surface to make the sand ash sink, and tick off the joints with cement mortar that meets the design requirements. The jointing must be completely hooked and pressed into the concave joint on the surface; After the mortar is solidified, it can only be used by sprinkling water for 7 days.