Subway station yard road and square engineering work focus and quality control standards
6.1. Subway station road and square project.
6.1.1. According to the Beijing Construction Engineering Technology Enterprise Standard QB (QBD-011-2005) "Rail Transit Station Road and Square Engineering Construction Quality Acceptance Standards" includes: subgrade engineering, grassroots engineering, pavement engineering, square engineering, sidewalk engineering, retaining wall engineering, ancillary structures and other seven divisions.
6.1.2. The construction site quality management and construction quality control of the station road and square project, and the construction quality acceptance shall be carried out according to (QBD-011-2005).1.4. Enforcement of Terms.
6.1.3. Key points of quality control of road and square engineering construction in the station:
The main materials, components and equipment used in the project shall be accepted by the construction unit for its appearance, specifications, models and quality certification documents, and the supervision engineer shall inspect and approve;Where it involves the structural safety and use functions of battlefield roads and squares, the construction unit shall conduct inspections, and the supervision unit shall conduct witness sampling and testing according to the specifications.
Each process is quality controlled according to the construction technical standards, and after each process is completed, the construction unit will inspect and form a recordSupervision inspects and inspects.
The construction unit carries out handover inspection between the processes, and the previous process meets the construction conditions and technical requirements of the next process;The handover inspection between the relevant professional processes shall be strictly inspected and approved by the supervising engineer, and the next process construction shall not be carried out without inspection or unqualified inspection.
6.2. Station road works.
6.2.1. Key points of quality control for perception.
The shoulder edge of the roadbed is clear and straight, and the slope is stable and smooth.
The layout of the subgrade drainage system is reasonable, and the drainage system of the station is coordinated, and the drainage is smoothThe drainage trench masonry is straight and the trench surface is flat.
The road pavement is smooth, the drainage is smooth, there is no stagnant water, the shoulder edge of the curb is clear and smooth, and the masonry is stable.
The road signs are complete, the handwriting and patterns are clear, the position is coordinated and reasonable, the signs are bright in color, the spraying is eye-catching, and the supporting structure is stable.
The road guardrail (parapet wall) is stable, linear and round, the position is coordinated and reasonable, and the height is moderate and uniform.
The road lighting is moderate, the position of the street lamp and its column is reasonable, the height of the lamps and power supply lines is reasonable, the power supply line is laid steadily and beautifully, and the laying of other pipelines in the station is coordinated.
6.2.2. Quality control standards for subgrade engineering.
Main control project: The earthwork density of the subgrade must comply with the following table:
Subgrade earthwork compaction (heavy compaction standard).
Subgrade earthwork compaction (light compaction standard).
General items: The allowable deviation of the fill and subgrade earthwork shall meet the following requirements:
The fill should be distinguished from different soil qualities according to the specified thickness of the layered backfill, and the fill shall not have slurry and spring phenomenon after rolling and tamping.
There shall be no impurities such as silt, humus and organic matter in the fill. The use of ballast soil should be strictly controlled, and in case of special circumstances, it can only be used after being identified by the relevant technical departments.
Subgrade earthwork allowable deviation.
Note: The b value in the width is the necessary additional width required for the construction of the superstructure.
Roadbed master control project:
The compaction of the roadbed, the elevation of the centerline and the deflection value shall comply with the following provisions:
Note: The unit of deflection value: 1 100mm
General items: The quality of the roadbed shall comply with the following provisions:
The road bed shall not have slurry, springs, peeling, waves, water accumulation and other phenomena.
After being rolled by a press of more than 12t for heavy-duty compaction standards and 10t or more for light-duty compaction, the depth of the wheel track shall not be greater than 5mm.
Allowable deviation of the road bed:
Note: The b value in the width is the necessary additional width required for the construction of the superstructure.
Shoulder Master Control Project:
The degree of compaction of the shoulder shall be in accordance with the following table:
General items: Shoulder surface quality and allowable deviation shall comply with the following regulations:
The shoulder line should be straight and smooth, and the surface should be smooth, and there should be no cracks and water blocking.
Permissible deviation of the shoulder:
6.2.3. Quality control standards for soil and stone ditches and slopes.
General items: (no master items).
The quality of soil and stone ditches and slopes should meet the following requirements:
The slope should be smooth, solid, stable, and not close to the slope.
The upper mouth line of the slope should be neat and straight, the bottom of the ditch should be smooth, and the drainage of the side ditch should be smooth.
The strength of masonry mortar should be in accordance with the design regulations.
Allowable deviation of soil and stone ditch and slope:
6.2.4. Key points of quality control of grassroots projects.
Quality management includes standard tests of the materials used, paving test sections, quality supervision and inspection and acceptance during construction (between processes).
It is necessary to establish and improve the system of site test, quality inspection and acceptance between processes. The test and inspection should be complete in the original records and the data should be true and reliable.
After the completion of each process, inspection and acceptance should be carried out. After passing the inspection, the next process can be carried out. Any paragraph that fails to pass the test must be remedied to bring it into compliance.
The pellets should meet the requirements of the design and construction specifications, and the quality of the pellets should be selected according to the local material source. 、
The quality of lime and fly ash should meet the design requirements, and the lime should be fully digested before it can be used.
The mixture ratio should be accurate, and should not contain ash mass and quicklime blocks.
When paving, attention should be paid to eliminating the segregation of coarse and fine materials.
When rolling, the light roller should be used to stabilize the pressure first, and then the heavy-duty roller should be rolled to the required degree of compaction.
Maintain a certain humidity for health, and the health period should meet the requirements of the specification.
6.2.5. Quality control standards for grassroots projects.
Limestone base main control project:
Limestone soil and limestone base layer should meet the following requirements:
The particle size of the limestone soil is greater than 20mm, and the particle size of the largest soil block shall not be greater than 50mm. The limestone soil should be mixed evenly and the color and luster should be harmonious. It is strictly forbidden to contain undigested particles and ash with a particle size greater than 10mm, and the lime should reach the above standards.
The unconfined compressive strength of limestone base shall meet the design requirements and the following table.
The degree of compaction of the limestone base shall comply with the provisions of the following table:
General items: The surface quality and allowable deviation of the limestone base shall meet the following requirements:
After rolling and forming with a roller of more than 12t, the depth of the wheel track shall not be greater than 5mm, and there shall be no floating soil, peeling and loosening.
Allowable deviation of limestone base layer:
Lime fly ash stabilized gravel (gravel) base master control project:
The unconfined compressive strength and compaction degree of lime fly ash stabilized gravel (gravel) base shall meet the design requirements and the following table:
General items: The materials and construction quality used in lime fly ash stabilized gravel (crushed) base shall meet the following requirements:
The quality of lime and fly ash, the grading of sand and gravel and the crushing rate should meet the requirements, the mud content should not be greater than the regulations, and the mixture ratio should be accurate.
The lime fly ash and gravel should be mixed evenly, and the color and luster should be consistent. The maximum particle size of gravel (gravel) is not more than 40mm;It is strictly forbidden to contain ash blocks with a particle size greater than 10mm for digestion, and the maximum aggregate shall not be greater than 50mm.
There is no obvious segregation of coarse and fine particles in the paving layer.
After rolling with a roller of more than 12t, the depth of the wheel track shall not be greater than 5mm;And there shall be no floating, molting, and loose phenomena.
The health period of lime and fly ash stabilized gravel (gravel) base shall not be less than 7 days.
The allowable deviation of the quality of lime fly ash stabilized gravel (crushed stone) base layer is shown in the following table:
6.2.6. Key points of quality control of pavement engineering.
The construction of asphalt surface course must be ordered by the supervising engineer before it can be started.
In the construction process, a full-time quality inspection agency should be responsible for the inspection and test of construction quality.
The construction unit shall conduct self-inspection of the construction quality at any time during the construction process. The supervising engineer shall conduct random inspection or side station inspection, and inspect and identify the self-inspection results of the construction unit. When the construction personnel, supervising engineers and supervisors find abnormal conditions, they should immediately report or add test inspections.
The construction unit must conduct sampling tests on various construction materials during the construction process, and the project and frequency shall not be less than the provisions of the specification, and the quality of the materials shall meet the requirements of the quality indicators specified in the specification.
The content, frequency and quality standards of engineering quality inspection in the construction process shall comply with the provisions of the specification. When the test results do not meet the specified requirements, the number of tests should be increased, the cause should be found, and the treatment should be carried out.
The asphalt mixture mixing plant should check the mixing uniformity, mixing temperature, factory temperature and the amount of each silo, and should take samples for Marshall test to detect the mineral gradation of the mixture and the amount of asphalt.
The quality of the mixture and the construction temperature should be observed at the mixing site, the thickness, compaction and flatness should be checked at any time, and the molding size should be determined section by section.
When controlling the construction thickness, in addition to measuring and measuring the thickness of the borehole specimen during paving and compaction, the average thickness calculated from the total amount of asphalt mixture on each day and the actual paved area should also be checked.
The inspection of the degree of compaction of construction should be subject to the drilling method. When checking with a nuclear densitometry, it should be converted by the calibration relationship with the density of the borehole, and the number of tests should be increased. When the indicators of drilling inspection continue to be stable and meet the quality control requirements, with the consent of the competent department, the drilling frequency can be appropriately reduced, the detection frequency of the nuclear densitometer can be increased, and the number of rolling passes can be strictly controlled. In this case, the frequency of drilling should not be less than one hole per kilometer. During the construction process, the drilled specimens should be numbered and labeled to be preserved, so as to be used when the project is handed over and accepted. The degree of compaction and the standard density shall be determined according to the method required by the specification.
The quality inspection results of the construction unit should be sorted out into a table according to 1km (highway) or 100m (urban road). When an abnormality is found, the construction should be stopped, the cause should be analyzed, the influencing factors should be found, and measures should be taken. Resumption of work can only be resumed with the consent of the competent authority.
The key processes or important parts of road construction should be filmed or videotaped, and kept as a real record.
6.2.7. Quality control standards for cement concrete (reinforced cement concrete) pavement engineering.
Cement concrete (reinforced concrete concrete) pavement main control project:
The compressive strength, flexural strength and thickness of cement concrete (reinforced cement concrete) pavement shall meet the design requirements and the following table:
General items: cement concrete (reinforced cement concrete) pavement construction quality should meet the following requirements:
The surface of the template is smooth, and the coating of the separator should be uniform and consistent.
The formwork installation should be firm, and the mold should not be tilted or runThe joint joint is tight, and there is no slurry leakage.
The corners of the cement concrete (reinforced cement concrete) slab surface should be neat, without cracks, and there shall be no exposed stones and floating slurry, molting, imprints, water accumulation and other phenomena;The surface of the concrete should be evenly drawn and the depth should be consistent.
There shall be no sundries in the seams, and the account seams must all be through;The force transfer rod must be perpendicular to the seam surface.
The straight section of the cut seam should be straight and smooth, and the curved section should be smooth, and there should be no blind seams and running saws. Guarantee the seam depth of the design.
The caulking material should be full, dense, and neat, and should not be leaked.
The allowable deviation of cement concrete (reinforced cement concrete) pavement formwork installation is shown in Table 1.
The allowable deviation of cement concrete (reinforced cement concrete) pavement is shown in Table 2.
Table 1 Allowable deviation of cement concrete (reinforced cement concrete) pavement formwork installation.
Table 2 Allowable deviation of cement concrete (reinforced cement concrete) pavement.
Note: The joint of the plate constructed by the cutting joint method does not measure the height difference of the adjacent plate.
6.2.8 quality control standards for asphalt concrete pavement.
Asphalt concrete pavement main control project:
The compaction, thickness and deflection value of asphalt concrete pavement shall meet the design requirements and the provisions of the following table.
Asphalt concrete pavement compaction, thickness and deflection value specified value or allowable deviation.
Note: The on-site concrete density measured by the wax seal method or the surface drying method is compared with the standard density measured by the Marshall stability meter test or the 30MPa pressure forming method
The degree of compaction in this table is based on the Marshall stabilizer compaction molding standard
Deflection value unit: 1 100mm;
Item 1 of this table can also be detected by automatic testing equipment;
Modified asphalt concrete pavement can be inspected with reference to this table;
The test methods of compaction degree and deflection value are shown in Appendix B and Appendix F of the Beijing Engineering Construction Standard "Construction Quality Inspection Standard for Urban Road Engineering (DBJ01-11-2004)", respectively.
General items: asphalt concrete pavement construction only comes to that and the allowable deviation should meet the following requirements:
The surface should be smooth and solid, and there should be no falling off, slag dropping, cracks, pushing, rotten edges, concentration of coarse and fine materials, oil spots, etc.
After rolling with a roller of more than 12t, there shall be no obvious wheel tracks.
The construction joints should be tight and smooth, and the hot joints should not be scorched.
The surface layer should be connected with the curb, flat stone and other structures, and other structures should not be polluted, and there should be no water accumulation.
The allowable deviation of asphalt concrete pavement quality is shown in the following table
Note: The leveler calculates the standard deviation for every 100m for continuous detection of each lane of the whole line;No leveler can be tested with a 3m rulerThe number of inspection frequency points in the table is the number of lines
Item 1 of this table can also be detected by automatic testing equipment;
The surface of the subbase should be sprinkled with permeable oil and sticky layer oil according to the amount specified in the design
Modified asphalt concrete pavement can be inspected using this table.
6.3 Square Project.
6.3.1. The key points of quality control of the square project.
The compaction of the roadbed and base should be smooth, the layout of the drainage system is reasonable, the drainage is smooth, the trench masonry is straight, and the trench surface is smooth.
The ground is smooth and drained, there is no stagnant water, the shoulder edge of the curb is clear and round, and the masonry is stable.
The logo is complete, the handwriting and pattern are clear, and the position is coordinated and reasonableThe logo is brightly colored, the spraying is eye-catching, and the support structure is stable.
The guardrail (parapet wall) is stable, linear and round, the position is coordinated and reasonable, and the height is moderate and uniform.
The lighting is moderate, and the position of the street lamp and its column is coordinated and reasonable.
6.3.2. Quality control standards for pavement brick square engineering.
Master project. The strength of cement mortar should meet the design requirements;The compaction degree of the roadbed and the base layer, the compressive and flexural strength of the pavement bricks should meet the following requirements:
Note: The degree of compaction in this table adopts the heavy-duty compaction standard.
General items. The paving should be smooth and stable, and the joints should be full, and there should be no warping.
The surface layer of the square should be connected with other structures, and there should be no water accumulation.
The allowable deviation of the pavement brick square is specified in the table below.
6.3.3. Quality control standards for on-site pouring cement concrete surface layer square engineering.
Master project. The degree of compaction of the roadbed and the base layer, the compressive strength and flexural strength of cement concrete should meet the design requirements and the provisions of the following table.
Note: The compaction degree of this table adopts the heavy-duty compaction standard.
General items. The corners of the board surface should be neat, there should be no cracks, and there should be no exposed stones, floating slurry, peeling, imprints and other phenomena.
The surface line should be neat and clear;The expansion and contraction joints should be cut and straightened in time, and the material of the caulk should meet the requirements.
The surface layer should be connected with other structures, and there should be no water accumulation.
The allowable deviation of the on-site pouring cement concrete surface layer square is shown in the following table:
6.3.4. Quality control standards for natural stone square projects.
Master project. The compaction degree of the roadbed and base layer shall comply with the provisions of the following table:
The strength of cement mortar should meet the design requirements;
The compressive and flexural strength of the stone should comply with the provisions of the following table:
The physical and mechanical properties of natural stone should conform to the Beijing Municipal Engineering Construction Standard "Urban Road Engineering Construction Quality Inspection Standard (DBJ01-11-2004)" Appendix J Table J12.2.
Note: The compaction degree of this table adopts the heavy-duty compaction standard.
General items. Stone paving should be smooth and stable, and there should be no warping;The mortar and grout joints are full, and the gaps are consistent.
The surface of the stone paving should be neat and beautiful, the masonry joints should be straight, and the color of the surface layer should be excessively natural and basically coordinated.
The surface layer of the stone should be connected with the curb and other structures, and there should be no reverse slope and water accumulation.
Natural stone squares allow deviations.
6.3.5. Quality control standards for asphalt concrete square projects.
Main control project: The compaction degree of the roadbed and base layer shall comply with the provisions of the following table:
The degree of compaction in this table is based on the heavy-duty compaction standard.
General project: asphalt concrete square construction and allowable deviation should meet the following requirements:
The surface should be smooth and solid, and there should be no falling off slag, cracks, pushing, rotten edges, and concentration of thick and fine aggregates.
The construction joints should be tight and smooth, and the ironing edges should not be scorched.
The surface layer should be connected with other structures, and other structures should not be polluted, and there should be no water accumulation.
The allowable deviation of the asphalt concrete square is shown in the following table:
6.3.6. Quality control standards for sidewalk engineering.
Main control items: the compaction of the roadbed and the base, the strength of cement mortar, and the compressive and flexural strength of pavement bricks should meet the following requirements:
The degree of compaction of the roadbed and roadbed should meet the requirements of the following table.
The strength of cement mortar should meet the design requirements;
The compressive and flexural strength of pavement bricks conforms to the provisions of the following table.
General requirements: the paving should be smooth and stable, the filling joints should be full, and there should be no warping.
The sidewalk and other structures should be connected smoothly, and there should be no water accumulation.
The allowable deviation of pavement brick sidewalks is shown in the following table:
Note: The independent sidewalk should be increased with an inspection elevation index, and the allowable deviation is 10mm.
6.3.7. Control standards for on-site pouring cement concrete sidewalks.
Main control project: the compaction degree of the roadbed and the base layer should comply with the provisions of the small standard;
The compressive strength and flexural strength of cement concrete should meet the design requirements.
General requirements: the corners of the board surface should be neat, there should be no cracks, no stones exposed, floating slurry, peeling, imprints and other phenomena.
The surface line grid must be neat and clear;The expansion and shrinkage joints should be cut in a timely and straight manner, and the material of the caulk should meet the requirements.
The surface layer should be connected with other structures, and there should be no water accumulation.
The allowable deviation of the on-site poured cement concrete sidewalk is shown in the following table:
6.3.8 quality control standards for natural stone sidewalks.
Main control project: The compaction degree of the roadbed and base layer conforms to the provisions of the following table.
The strength of cement mortar should meet the design requirements;
The compressive and flexural strength of the stone should comply with the provisions of the following table:
The physical and mechanical properties of natural stone should conform to the Beijing Municipal Engineering Construction Standard "Urban Road Engineering Construction Quality Inspection Standard (DBJ-11-2004)" Appendix J Table J12.2.
General requirements: stone paving should be smooth and stable, there should be no warping, mortar and grout joints are full, and the gaps are consistent.
The surface of the stone paving should be neat and beautiful, the masonry joints should be straight, and the color of the surface layer should be excessively natural and basically coordinated.
The surface layer of the stone should be connected with the curb and other structures, and there should be no reverse slope and water accumulation.
The allowable deviation of natural stone sidewalks is shown in the table below
Note: The independent sidewalk should be increased with an inspection elevation index, and the allowable deviation is 10mm.
6.4. Ancillary structure works.
6.4.1. Quality control standards for curb stone and flat stone engineering.
General projects: The construction quality of curb stone and flat stone should meet the following requirements:
The curb stone and flat stone should be stable, and the lines should be straight, the curve should be smooth, the surface should be clean and not polluted, the hook joints of the curb should be tight, and the flat stone should not block water.
The backfill behind the curb should be dense;If the back is backfilled with concrete, the mix ratio should meet the requirements.
The compressive strength of curb and flat stone concrete meets the design requirements.
Allowable deviation of curb stone and flat stone:
Note: Curbs and flat stones are divided into concrete or natural stone.
6.4.2. Quality control standards for bottom protection, slope protection, and masonry retaining wall engineering.
Main control project: masonry mortar must be caulking full and dense, and the compressive strength of masonry mortar should comply with the following table:
General items: bottom protection, slope protection, masonry retaining wall masonry and allowable deviation shall comply with the following provisions:
The ash seam is uniform and neat, the seam width meets the requirements, and the hook seam must not fall off or leak.
The masonry is layered and staggered, and the bite should be tight, and there should be no through joints.
The settlement joint should be straight through.
Embedded parts, drain holes, filter layers, waterproof facilities, etc. should meet the requirements of design and relevant specifications.
Dry masonry shall not be loose, stacked and floating.
The allowable deviation of bottom protection, slope protection and masonry retaining wall is shown in the following table
Note: h in the table is the full height of the structure.
6.4.3. Quality control standards for railings, floor blankets and handrails.
Main control project: The compressive strength of cement concrete should meet the design requirements and the following table, and the installation of railings, floor jackets and handrails must be firm.
General items: The production and installation quality of railings, floor jackets and handrails should meet the following requirements:
The caulking at the joints of the railing and the railing is full, and the expansion joints should all be through.
The cement concrete components shall not have honeycomb, exposed ribs and other phenomena, and the components shall not have defects such as hard injuries, corners and cracks after installation.
Railings, floors, and handrails should be straight and smooth, without skew or distortion. The welds of metal railings and handrails must be full, and there shall be no leakage of welding, desoldering, etc., and the paint surface must be completed, and there shall be no peeling, rust and other phenomena.
The allowable deviation of precast concrete railing members is shown in Table 1 below.
The allowable deviation of the installation of precast concrete railings, floor blankets and handrails is shown in Table 2.
Table IPrecast concrete railing members allow deviations