Engineering construction scheme
Chapter I Project Overview
The resettlement community is located in Fenghuang, with a total area of 21559.15m2 (including street sign area of 2565.24m2). The residential area is about 190m north of Langzhou Road in the east and about 1.5KM south of 207 national highway. There is a 3m-wide village road to the west, which temporarily leads to the urban planning road and municipal administration of the resettlement community. In order to ensure the smooth construction road and drainage requirements, as well as the living drainage and travel of the resettlement community, a construction access road is set between the community and the northern extension of Langzhou Road. The entrance to the north extension section of Langzhou Road is10m long and 6m wide.
1, compilation basis
Code and technical standard for municipal engineering construction.
Specific requirements for on-site guidance by the leaders of the construction unit.
The specific situation learned after on-site reconnaissance.
Our construction experience and strength of similar projects.
2. Project content
2. 1 road engineering
According to the general layout plan (scheme) of Phoenix Apartment Resettlement Community, the proposed construction access road is located opposite to the planned main entrance and exit, and in a straight line with the main entrance and exit road. The total length of the road 190m, the width of the road foundation (that is, the land occupied by the expropriated road, including the land occupied by the drainage pipeline) is 10m, and the hardening width of the pavement is 8m. The drainage pipe is buried under the shoulder foundation on one side of the hardened road. Reinforced concrete pipe diameter D600 is connected to Langzhou North Road.
2.2 Drainage works
2.2. 1 rainwater works: both sides of the diameter of D600 reinforced concrete drainage pipe are protected by C30 fine concrete, and the height is not less than 2/3 of the diameter. The interface is sealed with M 10 cement mortar, with steel wire mesh, width of 30㎝ and thickness of cement mortar of 5㎝. The rainwater outlet is connected in series and connected to the municipal rainwater pipe network system of Langzhou North Road.
3. Owner: Hunan TEDA Real Estate Co., Ltd.
Construction period: 45 calendar days
Quality grade: qualified
Chapter II Construction Deployment
1, project organization
1. 1 construction organization and management
According to the requirements of the site and time limit for a project, we decided to concentrate on the elite soldiers and powerful soldiers and mechanical equipment, and organize the construction according to the project method. The project consists of five main functional departments, namely, facilities technology department, security department, finance department, machine transportation department and back office department. The construction group is divided into road group and water supply and drainage group.
1.2 construction organization
Construction project manager, construction project deputy manager, project chief engineer, technician, materials, equipment, safety officer, quality inspector, surveyor and builder.
2. General arrangement of construction
According to the site situation, formulate feasible construction deployment, and arrange qualified full-time personnel to be responsible for quality management, schedule control, technical management, safety management and civilized construction management in the construction process.
3, the construction process deployment
3. 1 The project is located in a place with convenient water, electricity and roads, with offices, construction departments and supervision departments.
3.2 According to the actual situation on site, the construction direction is from low to high and from bottom to top to ensure smooth drainage.
3.3 Overall construction sequence: According to the design drawings, the project content is: Rainwater Road.
3.4 Access road: The road shall be constructed from east to west.
3.5 The project department shall contact the construction unit and other relevant departments in time for the use of water and electricity, and set up wires and water supply pipelines in time to ensure the construction of water and electricity.
Chapter III Construction Progress Plan and Guarantee Measures
1, construction preparation work plan
1. 1 joint review drawings. Understand the design intent, understand the quality requirements of each component project. Carefully analyze the factors that are not conducive to the progress of the project, determine the specific construction plan, and minimize the impact of unfavorable factors on the project. At the same time, the specific construction plan and other written materials will be submitted to the construction unit, design unit and supervision unit.
1.2 Prepare the construction organization design and submit it to the supervision engineer for review.
1.3 prepare materials, mechanical equipment and technical data related to finished products and semi-finished products.
1.4 Re-measure the original leveling points and road center coordinate points provided by the construction unit and the design unit, and notify the supervision engineer for on-site verification.
1.5 Provide the supervision engineer with the actual ground elevation of the measured site.
1.6 Do a good job of "three links and one leveling" on site.
2, the construction sequence
Site leveling → construction lofting → trench excavation → pipeline laying → masonry manhole → backfilling → road groove → cushion → paving → pedestrian walkway.
3. Safeguard measures
3. 1 Track the implementation of the schedule regularly, compare the planned value with the actual value of the project objectives, and take corrective measures when the project objectives deviate. In order to avoid the deviation of the project objectives again, we should carefully analyze various influencing factors that may lead to the deviation of the project objectives, and take effective preventive measures against these influencing factors. And form relevant written materials and report them to the construction unit, design unit and supervision unit.
3.2 On the premise of making the overall project plan, make a detailed road separation process plan to delay the sequence of each process.
3.3 During the construction period, the responsibility shall be effectively implemented to individuals, with a clear division of labor, and the construction progress shall be strictly guaranteed.
3.4 Reasonable arrangement of construction machinery and labor force to achieve the best utilization rate.
Chapter IV Main Construction Methods of Divisional and Subdivisional Projects
1, construction preparation
1. 1 staffing
Implement the division of tasks and do a good job in employee training. Regularly train the cadres and workers involved in the construction in labor discipline, skill safety and other aspects. , do a good job in team division of labor, do a good job in tool configuration, and clarify responsibilities and tasks.
1.2 mechanical preparation
Arrange and dispatch machinery and equipment according to the construction machinery plan, do a good job of maintenance before construction, refine the division of labor of machinery and equipment, and make a good oil supply plan to ensure that the equipment is transported to the designated place on time.
1.3 technical preparation
Organize personnel to learn technical standards and construction specifications, and conduct joint review of drawings disclosure and construction specifications. Make a detailed investigation on the site, including various construction conditions, such as power supply, water supply, roads, borrow sites, etc. Learn more about local people's feelings, climate and groundwater. Organize relevant technical management personnel to be familiar with the drawings carefully, and proofread them carefully in combination with the site conditions, prepare detailed construction operation plans, do a good job in process construction and technical disclosure, and do not enter the next process if the previous process is unqualified.
Go through the handover procedures, retest the center line and elevation piles, and set up protection piles immediately after confirmation.
Then according to the construction needs, add encryption points. In the survey, the usable building range and the positions of various structures were determined, and the natural elevation of the original ground was measured, which provided an accurate basis for construction survey and design review.
2. Rainwater engineering
2. 1 Site preparation
2. 1. 1 Determine the construction scope, and arrange the technical director to pay out according to the construction drawings before entering the site with qualified surveyors.
2. 1.2 Investigate the location of underground water, electricity, gas and other pipe networks in detail, and take measures such as relocation or local protection in combination with the actual situation.
2. 1.3 Use bulldozers and loaders to level the site.
2.2 Rainwater Pipeline Foundation
2.2. 1 When there is no groundwater in the ditch, 12% lime-soil foundation should be adopted. Put it directly into the tank bottom with loader, spread it manually, and tamp it with frog rammer until it meets the requirements.
2.2.2 When there is groundwater in the ditch, use 20cm gravel cushion and spread 10cm medium sand. By artificial paving, frog rammer compaction, until it meets the requirements.
2.2.3 In case of soft foundation, a feasible and economical treatment scheme shall be formulated, and written materials shall be submitted to the supervision engineer. After being approved by the supervision engineer, the construction shall be carried out according to the established scheme.
2.3 pipeline laying
2.3. 1 When the pipeline enters the site, it shall be visually inspected and the certificate of conformity shall be checked.
2.3.2 Pipeline installation shall be carried out after the foundation and pipeline foundation are qualified, and the installation shall start from the downstream.
2.3.3 Pipeline stacking is convenient to use and should be stacked after leveling the site. Before pipeline installation, pipelines and fittings shall be placed in the construction sequence, lowered by crane and installed manually.
2.3.4 Use a level to control the elevation of the pipeline. For each pipeline, the next pipeline can only be installed after the elevation and design are correct.
2.4 Trench backfill and compaction
2.4. 1 Well is tamped with frog rammer within the range of1m.. The loader cooperates with the excavator to mix 2:8 lime soil on the ground, and the loader sends the soil down, which is artificially leveled. The virtual paving thickness is 200mm, and the height difference on both sides shall not exceed 30cm. Backfill soil shall not contain bricks, stones and hard soil (frozen soil) larger than 10cm.
2.4.2 Backfill soil or other backfill materials shall not damage the pipe joint and its interface when transported into the tank, and shall comply with the regulations: stones, bricks and other sundries larger than 100mm shall not be backfilled within 500mm of the pipe top; When backfilling, there shall be no water in the tank, and silt, humus, frozen soil and organic matter shall not be backfilled.
2.4.3 Backfill materials shall be transported to the trough according to the virtual paving thickness of a layer, and materials shall not be piled up within the range that affects compaction.
2.4.4 Backfill materials on both sides of the pipeline and 50 cm above the top of the pipe shall be symmetrically transported into both sides of the groove, and shall not be pushed centrally.
2.4.5 Backfill materials that need to be mixed shall be mixed evenly before being transported into the tank, and shall not be mixed in the tank.
2.4.6 Trench backfill shall be carried out under the existing road, and the 80cm range under the subgrade shall be compacted by layers with 2: 8 lime soil.
The compactness is above 95%. The trench below 80cm under the subgrade is backfilled with plain soil, and the density meets the specification requirements.
3. 1 Trenching
Before trench excavation, it is necessary to find out the underground conditions related to construction.
3. 1. 1 Manual excavation combined with surveyors to accurately control the elevation. It is forbidden to dig without affecting the safety of people and things.
3. 1.2 During trench excavation, professionals shall be arranged for guidance.
3. 1.3 Trench excavation quality
3. 1.3. 1 undisturbed natural foundation or foundation treatment meets the design requirements.
3. 1.3.2 The groove wall is flat and meets the construction design requirements.
3. 1.3.3 The clear width on both sides of the center line of the trench shall not be less than half of the excavation width at the bottom of the trench.
3. 1.3.4 Allowable deviation of trough bottom elevation: 20mm； during earthwork excavation; When excavating stone, it should be 20 mm
3.2 Lower the drill pipe
Check the groove before running the pipe and make necessary treatment. Pipeline stacking is convenient to use, and it can be stacked after leveling the site. Before pipeline installation, pipes and fittings shall be placed in the construction order.
3.2. 1 Clean the sundries at the bottom of the tank.
3.2.2 The width of the trough bottom shall ensure the working width of each side of the pipeline structure.
3.2.3 The elevation shall conform to the current inspection standards, and the unqualified ones shall be trimmed or treated as required.
3.2.4 Use a level to control the elevation of the pipeline. For each pipeline, the next pipeline can only be installed after the elevation and design are correct.
Trench backfill should have different requirements for different parts to protect pipeline safety and meet the upper load; It is necessary to ensure the safety of the pipeline during construction and the safety of the upper part after the road is repaired.
3.3. 1 Both sides of the trench shall be backfilled and compacted at the same time to prevent the pipeline from shifting.
3.3.2 Other pipelines or structures crossing this pipeline shall be properly handled during backfilling.
3.3.3 Within 500mm of the pipe top, stones, bricks and other sundries larger than 100mm shall not be backfilled.
3.3.4 When backfilling, there shall be no accumulated water in the pool, and silt, humus, frozen soil and organic matter shall not be backfilled.
3.3.5 The compactness of backfill soil shall comply with relevant regulations.
4, road engineering
4. 1 subgrade engineering
4. 1. 1 construction lofting:
Restore the center line on the subbase, set a pile every 20cm for the straight line segment, set a pile every 15cm for the flat curve segment, and set indicator piles on both sides of the shoulder edge.
Carry out horizontal survey, and mark the design height of the edge of lime stabilized soil base with obvious marks on the indicating piles on both sides.
4. 1.2 excavation adopts "tunnel longitudinal excavation method" to excavate the excavation section of the site.
Due to the tight construction period of this road project, "tunnel longitudinal excavation method" is adopted. Bulldozers and excavators are combined, and the subgrade will be formed as soon as possible when the soil conditions permit.
4. 1.2. 1 subgrade construction process flow chart
Preparatory work/about to start work
Center pile elevation measurement slope → measurement lofting.
Site cleaning → foundation treatment
Geotechnical test → subgrade filling
Self-inspection and spot check → leveling and compaction
Subgrade reinforcement
Pavement laying
Health maintenance
Inspection before acceptance
4. 1.2.2 Determination of construction scope: Before entering the site, arrange the technical director to survey the construction scope and road center line to the site according to the construction drawings, and mark them with white lines.
4. 1.2.4 The filling section of the construction site adopts "layered filling method" for layered filling. Using three-wheel roller combined with grader, the subgrade can be formed at one time under the condition that the compactness meets the requirements.
4.2.2 Use aggregate in the yard.
Before collecting aggregate, trees, turf and miscellaneous soil should be removed.
Oversize particles in aggregate should be screened out.
Aggregates shall be collected within a predetermined depth range, and shall not be collected in layers, and unqualified aggregates shall not be collected together.
For cohesive soil with plasticity index less than 15cm, whether screening is needed can be determined according to the soil quality and mechanical properties during mechanical mixing. Hydrated lime should pass through a sieve with the aperture of10mm and be used as soon as possible.
4.3 Paving aggregate
4.3. 1 The loose paving coefficient (or compaction coefficient, that is, the ratio of loose paving dry density to compacted dry density of the mixture) of the aggregate shall be determined by experiments in advance.
4.3.2 Paving aggregate shall be carried out on the day before spreading lime, and the paving length shall be sufficient for adding lime, mixing and rolling the next day according to the needs of daily progress. For roads that cannot be closed and rainy season, aggregate should be distributed on the day of lime distribution, mixing and rolling.
4.3.3 Use a grader to evenly spread the material on a predetermined width, and the surface should be as flat as possible, with a specified road arch.
4.4 Watering and drilling materials
If the soil is too dry, water should be sprayed in advance to make the soil water content meet the construction specifications.
4.5 mixing
4.5. 1 On the construction surface, according to the tested loose paving coefficient, the soil will be evenly paved on the qualified subgrade according to a certain thickness.
4.5.2 Spread fully digested lime evenly on the prepared soil.
4.5.3 Mix with stabilized soil in normal operation. When mixing, pay attention to ensure that the mixing areas overlap and there is no plain soil interlayer in the mixed lime soil.
4.6 Rolling
4.6. 1 Rolling method: First, from the edge of one side of the road, press 1/2 of the outer wheels on the subgrade. At the speed of 5 ~ 6 km/h, every time the heavy wheels overlap 1/2 ~ 1/3, they will gradually press to the center of the road, and then press to the center of the road from the other side edge. After leveling, the mixture is compacted for 4 ~ 6 times to meet the design requirements.
4.6.2 With a roller of 12t or more, roll it from the roadside to the center of the road for 4 ~ 6 times, and the degree of compaction can meet or approach the requirements. Check immediately. If it is found that the compaction degree does not meet the requirements, make up the pressure as soon as possible.
4.6.3 Lime soil shall be rolled in time after finishing to survive on the same day.
4.7 Plastic Surgery
4.7. 1 After the mixture is evenly mixed, it will be leveled and shaped in a straight line with a grader, and the grader will level it from both sides to the center of the road; In the flat curve section, the grader should be leveled from the inside out, and then returned to be leveled if necessary.
4.7.2 Use a grader to quickly roll 1 ~ 2 times. To expose the potential unevenness, and then reshape and roll again according to the above requirements.
4.7.3 Every plastic surgery should be carried out according to the specified slope and road arch, and special attention should be paid to the leveling of joints to ensure the smoothness of joints.
4.8 health preservation
4.8. 1 curing is an important process in lime-soil base construction, which directly affects lime-fly ash macadam base.
4.8.2 After the lime-soil construction is completed, it shall be maintained by sprinkling water in time to maintain a certain temperature. The surface maintenance period of lime soil after construction in normal temperature season is not less than 5 ~ 7 days. The curing method can be sprinkling water, covering sand or clay, or impermeable film and asphalt film. During the maintenance period, no other vehicles are allowed to pass except the sprinkler.
4.9 Technical measures for quality of lime-soil base and subbase
4.9. 1 The properties of soil should meet the design requirements, and clods should be crushed.
4.9.2 The quality of lime should meet the design requirements, and the lime can be used only after it is fully digested.
4.9.3 The dosage of lime and soil shall be accurately controlled according to the design requirements, and undissolved quicklime blocks shall be removed.
4.9.4 The depth of road mixing should reach the bottom of the layer.
4.9.5 When the mixture is in the optimal water content state, it will be rolled to the required degree of compaction with a heavy roller.
4.9.6 Moisturize and preserve health, and the storage period shall meet the requirements of the specification.
4. 10 lime-fly ash macadam base
4. 10. 1 The central station centralized mixing method is adopted in this bid, and its technological process is as follows:
The lower level is qualified.
Measuring unreeling
Peishou avenue
Factory-mixed lime-fly ash macadam pavement
Detect ash dosage and water content
Do plastic surgery
repair
submerge
Health maintenance
4. 10.2 Technical requirements for construction:
When preparing lime-fly ash macadam, the ingredients should be accurate and the water content should be slightly higher than the optimal value, so that the water content of the mixture can be close to the optimal value when it is rolled after paving.
Uniform mixing: Before the lime-fly ash macadam mixture is mixed formally, the factory mixing equipment used must be debugged first, and the particle composition and water content of the mixture used should meet the specified requirements.
During construction in rainy season, measures should be taken to prevent lime, fly ash and aggregate from getting wet.
4. 1 1 Transportation and paving
4. 1 1. 1 When loading dump trucks, in order to prevent the mixture from separating, load them in two or three times, and transport them to the site for paving and compaction as soon as possible after each loading.
4. 1 1.2 The stacking time of the mixture shall not exceed 24 hours, and the mixture shall be transported to the paving site for paving and compaction on the same day.
4. 1 1.3 Before paving, adjust the virtual paving thickness and cross slope of the road to meet the design requirements. According to the production capacity of centralized mixing station, adjust the speed of paver to suit it, and reduce the number of paving stops. In the process of paving, check the smoothness elevation of the road surface with a three-meter ruler and a level meter, and adjust the cross slope in time.
4. 1 1.4 behind the paver, a special person shall be assigned to eliminate segregation of coarse and fine aggregates, especially the local coarse aggregate pits or coarse aggregate belts, and the mixture shall be filled or supplemented with new mixture and mixed evenly.
4. 12 scrolling
4. 12. 1 rolling method: when rolling, use a light roller to stabilize it, and then use a heavy roller to roll it to the required degree of compaction. Starting from one edge of the road, the outer wheel 1/2 is pressed on the subgrade. At the speed of 5 ~ 6 km/h, every time the heavy wheels overlap 1/2 ~ 1/3, they gradually press to the center of the road, and then press to the center of the road from the other side edge. After rolling again, the flatness should be carefully checked to meet the specified requirements. After leveling, the mixture is compacted for 4 ~ 6 times to meet the design requirements.
4. 12.2 Use a roller of 12t or above to roll it from the roadside to the center of the road for 4 ~ 6 times, and the compactness can meet or approach the requirements. Check immediately. If it is found that the compaction degree does not meet the requirements, make up the pressure as soon as possible.
4. 12.3 Lime-flyash macadam shall be rolled in time after finishing, and survive on the same day.
4. 13 combined therapy
4. 13. 1 transverse joint: after compaction, the end slope is 1:2. When the second construction begins, a stabilized soil mixer shall be arranged to stir the transverse joints for 2 ~ 3m.
4. 13.2 longitudinal joints: longitudinal joints should be avoided as far as possible. If it is inevitable, a stabilized soil mixer shall be arranged to mix 50cm into the joint and put it in place during rolling.
4. 13.3 The overlapping part of two engineering sections shall be in the form of butt joint. After the first stage of mixing and leveling, keep it for 5 ~ 8m without rolling. When the latter section is constructed, the uncompacted part left in the previous section will be rolled together.
4. 13.4 At the end of the reserved length, dig a groove across the whole width, put two square trees with the same compaction thickness in the groove, backfill the other side of the square trees with plain soil for 3 ~ 5m, and then carry out plastic rolling. Before re-construction at the grass-roots level, remove plain soil and square timber.
4. 14 quality requirements of lime-fly ash macadam
4. 14. 1 granular materials shall meet the requirements of design and construction specifications, and solid and clean granular materials shall be selected according to local material sources. Molten slag should be decomposed stably, and undissolved slag blocks should be removed.
4. 14.2 The quality of lime and fly ash should meet the design requirements, and the lime should be fully digested before use.
4. 14.3 The mixture ratio shall be accurate, and shall not contain ash blocks and quicklime blocks.
4. 14.4 When paving, attention should be paid to eliminating the segregation of fine materials.
4. 14.5 Keep a certain humidity for health preservation, and the health preservation period should meet the requirements of the specification.
4. 15 Pavement Quality Control
4. 15. 1 Before each construction, close the leveling points, restore the center line, and adjust in time when problems are found.
4. 15.2 Three self-inspection personnel are required for each construction to follow the paver to detect flatness, width, elevation, cross slope, etc. Deal with problems found in time, set up 1 inspectors, organize sampling inspection of projects, and make records and visas. After the completion of each section of construction, timely check and accept, provide measured data, fill in inspection records and forms, apply for inspection as soon as possible, and timely measure and pay.
Chapter V Quality Assurance Measures
In order to ensure the realization of the quality objectives of the project, the project runs according to the quality management and quality assurance system standards stipulated by the state.
1 Train all construction technicians and quality management personnel to control the whole construction process.
2 before the project starts, organize the project quality management personnel to review the drawings, carefully write the construction plan, make technical disclosure, and prepare for the construction technology in advance.
3. Organize operators to learn the acceptance criteria for engineering construction, so that all operators can master the control objectives of the project and conduct acceptance in strict accordance with the design requirements of drawings and the current acceptance criteria for construction.
4. Implement the project quality management responsibility system, decompose the quality objectives into people, strictly implement the reward and punishment regulations, and eliminate the fittest to ensure the quality of construction quality management personnel.
5 completes the quality control counter, to prevent quality common fault.
6. Set up a special quality inspection organization, and the quality inspection personnel will hold relevant certificates, select qualified measuring tools and conduct quality inspection. Organize data in strict accordance with the requirements of the construction acceptance specification, ensure that the data are accurate, neat, clear and complete, and ensure that the technical data are synchronized with the construction.
7 The concealed works shall be inspected by the supervision department in time after each work is completed, and can be transferred to the next working procedure only after being confirmed, and shall not be covered without authorization.
8. Strictly manage materials, and inspect the materials according to the design requirements and national standards. Unqualified materials are not allowed to be used. Various tests and inspections of materials are listed and marked, and stored in different areas.
9 engineering warranty. After the completion of the project, within the warranty period of the contract, after receiving the notice, organize personnel to carry out maintenance in time, do a good job in service with the idea of "customer first", organize quality return visits, and serve users wholeheartedly.
Chapter VI Warranty Measures
1. At the same time, provide the completion acceptance report to the construction unit, submit the quality warranty, and specify the warranty scope, warranty period and warranty responsibility of the project.
2. Organize professionals to pay regular visits, check the project status and maintain it in time.
3. On the second day after receiving the maintenance notice, organize personnel to enter the site for maintenance.
4. Repair all quality problems caused by construction during the warranty period. And all bear the responsibility for free.
Chapter VII Construction Drawing