Construction project quality common disease prevention and control program

Part 1: Construction project quality common disease prevention and control program

In order to further reduce the quality problems existing in the housing construction project of our city and effectively improve the quality level of the building construction project, the Wuxi Construction Bureau will organize the design, construction, supervision units and the city construction project quality supervision station and the city construction drawing design review center. According to the current national standards and standards, combined with the practice of building construction engineering in our city, we have prepared special prevention and control measures for the three common quality problems of “door and window leakage”, “roof leakage” and “external wall leakage”. Send and submit the following requirements, please implement them carefully.

1. From the date of the publication of the text:

1. New construction projects shall incorporate relevant quality control measures into the construction drawing design files in accordance with the requirements of this notice.

2. If there is no and no construction in the original design of the construction in progress, the design unit shall issue a design change according to the corresponding quality control measures, and any major changes shall be submitted to the review agency for review.

3. If the drawing design has been carried out but the project has not been started, the design drawings shall be adjusted or changed according to the requirements of this notice; if the construction drawing has been completed, the design drawings shall be changed accordingly, and any major changes shall be submitted to the reviewing agency for review.

2. Wuxi Construction Engineering Quality Supervision Station and Wuxi Construction Drawing Design Review Center are responsible for the daily supervision and management of the implementation of quality common disease prevention and control measures. In the course of implementing this notice and in the course of engineering practice, all units should promptly report back to us the problems and suggestions encountered so that they can be absorbed and referenced in the next revision. Please refer to Wuxi Construction Drawing Design Review Center for telephone design: 0510-82720911. For other questions, please report to Wuxi Construction Engineering Quality Supervision Station, Tel: 0510-85879031.

3. The quality and common disease prevention and control measures required by this notice are included in the excellent design and evaluation system of “Taihu Cup” quality project.


Part 2: Construction project quality common disease prevention and control program

The XX plot is a high-end residential plot developed by Henan XX Real Estate Co., Ltd., which was contracted by Shanghai XX Construction Co., Ltd. and supervised by Shanghai XX Construction Supervision Consulting Co., Ltd. Due to the common quality of residential projects, it is highly prone to residential projects. Quality problems, prevention and treatment of common diseases involve design, owner, supervision, construction and other relevant parties and various construction stages. It is the unshirkable responsibility and obligation of all parties to solve the problem of quality and common diseases, in order to ensure the effective quality in construction. Control, to overcome the common problems of quality, we have formulated the following measures and systems:

I. Organizational measures

Establish a quality common disease prevention and control team. The group is as follows:

Team leader: × × deputy leader: × ×

Group member: × ×

Permission, responsibility, scope of the prevention team

1. The permission of the quality common disease prevention and control group: If the prevention and control team finds that the quality common disease prevention and control plan has not been approved by the supervision party and the construction party, it has the power to order the construction team to rectify within a time limit; if there is no rectification or rectification, the right to carry out the economy Punishment even requires rework and rectification.

2, the responsibility of the quality common disease prevention team: try to eliminate the quality problems caused by construction reasons.

3. Scope of responsibility of the quality common disease prevention and control team: The construction quality involved in our project is a common problem.

Second, management measures

1. Before the commencement of the project, prepare quality control measures for common diseases, and provide technical disclosure to all management personnel to enhance the quality awareness of construction workers;

2. The decoration and decoration project must be “planned and the model is first”. The model room must be supervised and approved by the owner before construction.

3. Establish the handover and signing system of the process;

4. Establish a finished product protection system and send it to all participating parties.

Third, contract management measures

In order to do a good job in the quality control of the project, after the approval of your plan, the plan will strive to construct according to the construction specifications and quality assurance measures on the basis of no increase in cost; on the basis of increasing the cost, the requirements for quality control measures In order to ensure the serious implementation of the project quality control measures.

Fourth, technical measures

1. Common quality problems in concrete engineering

Common common quality problems in concrete engineering are: pockmark, honeycomb, rotten root, exposed ribs, gap and slag layer, floor crack, component geometry deviation, elevation deviation.

Reasons and prevention measures:

a, honeycomb: the reason is that the concrete is too thick at one time, the vibrating is not real or the vibration is lost, the template has a gap to make the cement slurry lose, the steel bar is dense and the concrete slump is too small or the stone is too large, the column and the wall root template have gaps. As a result, the mortar in the concrete emerges from the lower part.

When the concrete is constructed, the proper slump is maintained. When the height of the material is more than 3m, the stringer or chute is used. The joint of the formwork is squeezed with double-sided tape. The vibrator is listed on the post, standard operation, and enhance the sense of responsibility and quality. .

b. Exposed ribs: The reason is that the displacement of the steel blocks is too large, the spacing is too large, the leakage of the steel bars, the reinforcement of the steel bars close to the formwork, or the vibration of the bottom of the beams and plates is not true, and the exposed bars may also appear.

The side of the wall column, the bottom of the board uses the finished pad with grooves, the spacing meets the requirements of the plan, the support height of the horse bar between the two-layer plate ribs should be correct, and the lashing should be firm.

c. Pockmark: The mold is removed too early or the surface of the template is not enough to wet the release agent or the template. The surface of the component is easy to adhere to the template to cause peeling of the pockmark.

Before the concrete is poured, the formwork should be watered and wet, but there should be no water accumulation. The façade formwork should be removed after the concrete is finally set and has a certain strength. When the concrete is removed, the hard raft should not be pulled. Pay attention to the protection of the corners of the concrete members.

d. Gap and slag layer: It is easy to cause gaps and slag layer because the debris in the construction joint is cleaned or not poured.

The garbage cover on the beam board is blown off with a hair dryer. The wall column should be cleaned and the 50mm thick paste should be poured before the concrete is poured to ensure the organic combination with the original concrete surface.

e. The deviation of the section size of the beam and column connection is too large. The main reason is that the column joint template has poor rigidity or the section size is not carefully controlled when supporting the part.

The method of supporting the beam at the beam and column joints is strictly in accordance with the template scheme, and the quality inspectors carefully inspect and review the core.

f. The deviation of the flatness of the cast-in-situ floor surface and the stair step is too large or the pedaling is serious. The main reason is that after the concrete is poured, the surface is not evenly smoothed by the trowel, and the pedaling is serious because the caster is too early.

When concrete is poured, the face-receiving work should be done carefully. After the final setting, the strength is not allowed to pass before 1.2Mpa.

g, the thickness of the floor is not enough or the thickness of the board exceeds the standard

Before the concrete is poured, the top elevation of the floor slab formwork is checked, and the control mark of the cast-in-place slab thickness is made. During the pouring process, the quality inspector should carefully check the top mark of each slab.

Reserved holes can be used for inspection when there are reserved holes.

The repair of concrete defects is completed within 24 hours after demoulding, to distinguish different defects, and take the following measures:

Surface plastering. Surface sizing can be applied to pockmarks, exposed ribs and honeycombs. In the repair, the defect part is first cleaned, the loose stone is removed, the surface is wet and the water is not accumulated, and then the cement mortar which is mixed with the original design by the laboratory formula is smeared, and the surface should be complemented. The surface of the structure is flush and smooth, and no mutation can occur.

Concrete backfilling. For some voids, vertical molds are required for concrete backfilling. When repairing, first remove the defects until the dense concrete and ensure that the surface can not have sharp corners, then clean the surface and keep it moist and can not accumulate water, then backfill with the special repair micro-expansion fine stone concrete with the same grade as the original design, the backfill must be It is combined with the old concrete to ensure the compaction. The part protruding from the outer surface of the structure should be chiseled and smoothed after the initial setting of the concrete, and the curing is strengthened.

When the concrete is rolled up, the rough mold is used to roughly cut the mold, and then the surface is smeared with a fine tweezers, and the sander is partially polished.

2, the common quality problems of the internal wall

Masonry wall crack prevention measures:

a. The masonry mortar is medium coarse sand.

b. The parking period of the aerated concrete block should not be less than 28d. After the masonry structure is completed, it should be plastered after 30d. Pay attention to the steel mesh between different substrates.

c. When filling the wall to the bottom of the beam and the bottom of the board, there should be a gap of 150mm~200mm. After the wall is built and separated by 7d, the brick can be tightly ground and the mortar is full.

d. When the masonry wall is connected with the vertical concrete members, the ash gap should be full; when the aerated concrete block is used to build the outer wall, the scaffolding should not be left.

e. The position of the anchor ribs should be correct, match the brick modulus, and cannot be bent into the brick joints.

f. There should be no horizontal concealed pipe in the wall. If it cannot be avoided, the concealed pipe should be buried in the local cast-in-place concrete member. Vertically laid. When the diameter of the concealed pipe is less than 30mm, it can be directly applied to the masonry. In the middle, the multi-tube can be tied with a wire section, and the pipe is filled with mortar.

g. Vertical pipelines should not be buried in small load-bearing wall sections and wall columns with a width less than 500mm; if it cannot be avoided, it should be placed in the cast-in-place reinforced concrete structure. If this occurs, it should be negotiated with the designer. Design changes or on-site visas.

h. When trenches or holes are drilled in the aerated concrete block wall according to design requirements, it is strictly forbidden to disturb the wall by impact load.

i. The top and bottom outer windows of the masonry project shall be set with a cast-in-place reinforced concrete sill beam with a height of not less than 100 mm and consistent with the modulus of the brick. The concrete strength is not less than C20.

The cracks in the light partition wall mainly occur at the junction with other walls or above the door and window openings. The control measures are as follows:

a, should pay attention to hanging steel mesh between different substrates.

b. Doors, windows, openings, etc. shall be strengthened in strict accordance with the Taibo board industry standard and the treatment plan proposed by the professional subcontractor.

c. The wall of the wall should be reinforced with steel mesh.

Internal plaster quality control measures:

a. The base layer must be cleaned before the plastering is done, and watered and moistened one day in advance; the surface dust must be cleaned before wiping the surface.

b. The base layer must be bristled, the thickness of the bristles should be uniform, and the base layer should be watered and maintained after the bristles, and the strength is up to the handcuffs.

c. At the intersection of two different substrates, the wire duct should be grooved, and the wire mesh plaster should be used for strengthening treatment. The width of the reinforcement belt and each base should not be less than 150mm.

d. The plaster on the back of the fire box with the flue plastering and recessed walls must be full of steel mesh.

e. The ash on the inner wall surface should be from top to bottom. Construction shall not be reversed.

f. When moving the frame, be careful not to damage the wall surface, strengthen the education for the workers, and do not scribble on the plastered wall.

g, wall, column angle should be smeared into a circular arc shape, as required: 1:2 cement mortar corner protection, the height should not be less than 2m, the width of each side should not be less than 50mm.


Part 3: Construction project quality common disease prevention and control program

In order to improve the quality of the project, overcome the common problems of the quality of the residential project, and effectively guide the project quality control work, according to the actual progress of the site and refer to the "residential quality control of residential projects", the following quality common disease prevention and control construction plan is formulated.

First, the technical measures to prevent wall cracks

1, 10-13# Building masonry project, the bottom layer, the eleventh floor and the top floor sill room sill set the long cast-in-place reinforced concrete sill beam, the concrete strength grade is C20, the height is 120mm, the main rib is 4φ10, hoop φ6@ 200; the main rib is bonded to the concrete anchorage of the shear wall at both ends. 10-13# The second, third, fourth, fifth, sixth, seventh, eighth, ninth and tenth floor sills of the building are set with cast-in-place reinforced concrete slabs; C20 concrete with longitudinal reinforcement of 3φ8 and thickness of 60mm.

2. The masonry mortar of the bottom layer, the eleventh layer and the top layer of the hop layer is changed from the original designed M5 mixed mortar to the M7.5 mixed mortar.

3. Because the infill wall brick material of this project is made of small bricks, C20 concrete waist beam must be set in the middle of each wall height. The longitudinal reinforcement is 4φ8, the stirrup is φ6@200 and the thickness is 120mm, and the width is the same as the wall thickness.

4. The long cast-in-place reinforced concrete slab should be completed once.

5. The tie bars between the main body and the balcony fence must be pre-buried.

6. At the intersection of two different substrates, wire mesh plastering shall be adopted, and the overlapping width of the steel mesh and each substrate shall not be less than 150mm. The top-layer stucco mortar is blended with anti-cracking fibers. The top frame is filled with walls, and the wall is covered with steel wire mesh and other necessary measures.

7. External wall insulation measures such as 20mm for the west, north and east exterior walls and balconies, and 10mm for the south wall.

8. The masonry mortar is strictly made of medium coarse sand, and the 8mm aperture sieve is used, and the mud content is not more than 3%.

9. When filling the wall to the bottom of the beam and the bottom of the board, a gap of 200mm should be left. After the infill wall is completed and separated by 15d, the slanting bricks can be tightened; when the building is completed, the double-sided vertical joints are embedded with high-grade cement mortar.

10. The ribs of the infill wall between the frame columns should meet the strength requirements. The length of the ribbed ribs should be no less than 1 m and should be set at 2, and the number of ribs should be set according to the thickness of the wall. The vertical spacing is 50 cm. The bend is pressed into the brick joint.

11. A structural column shall be provided when the door opening, the corner and the wall length are more than 3 meters.

12. The intersection of the infill wall and the frame column is covered with 15mm*15mm wood strips, and the water is wetted before the mesh is applied, and then embedded with 1:3 cement mortar.

Second, the technical measures for the prevention and control of floor leakage

1. Waterproof insulation is set on the building floor with waterproof requirements such as kitchen and bathroom. The height should be greater than 200, the thickness is the same as the wall width, and the cast-in-place surface is poured at one time.

2. Before the pipeline is installed, the smooth outer wall of the upper and lower water pipes within the thickness of the floor slab should be first treated with a blanking treatment, and then evenly layered with 401 plastic glue, and then sprayed with the coarse sand of the sieve.

3. Before the reserved hole of the cast-in-place plate is blocked, the hole should be cleaned, textured, and coated with cement slurry as the bonding layer. The filling of the hole is divided into two times. Firstly, the micro-expanded fine stone concrete penetrating into the anti-cracking and anti-seepage agent is poured to 2/3 of the thickness of the floor. After the concrete is solidified, the water storage test is carried out for 4 hours; after no leakage, the anti-cracking is used. The cement mortar of the anti-seepage agent is clogged. After the pipeline is installed, a 24h water storage test should be carried out at the entrance.

4. Before the construction of the waterproof layer, the floor should be cleaned first, the powder at the corner of the corner should be made into a small arc, and the height of the waterproof layer should not be less than 300mm.

5. The ground leveling layer is 1~1.5% to the ground leakage, and the ground leakage is 5mm lower than the adjacent ground.

6. After the ground with waterproof requirements is completed, a 24h water storage test should be carried out, and the water storage height is 20~30mm.

7. The polymer waterproof mortar is painted in the range of 300mm upwards of the flue.

8. The wall waterproofing mortar of the bathroom should be shaved no less than 2 times.

Third, the technical measures to prevent leakage of external walls

1. The surface of the exterior wall is infiltrated with polypropylene anti-cracking fiber.

2. For exterior wall painting, use medium coarse sand with mud content less than 2% and fineness modulus not less than 2.5. It is strictly forbidden to use stone powder and mixed powder.

3. The exterior wall paint is sampled before use.

4. The plastering project does not use expired cement, and its setting time and stability must be qualified.

5. The external wall hole should be left in accordance with the specification. The half brick and waterproof mortar should be used for secondary blockage. The surface should be made of 1:3 waterproof mortar powder. The small round hole should be densely packed with micro-expansion cement mortar. The hole is blocked by a special person, and the special concealed acceptance procedures are handled in time.

6. The exterior wall painting base layer should be treated with interface agent mortar to be textured, and water spray curing should be carried out. When the deviation of the flatness of the base layer exceeds the standard, local chiseling is performed, and then repaired with polymer cement mortar.

7. Remove dirt from the wall before painting and water it a day in advance.

8. The plastering of the exterior wall is carried out in layers. It is strictly forbidden to survive once. The thickness of each layer is controlled at 6~10mm during construction. The joints of the outer wall are staggered and set in the middle of the concrete beam and column.

9, the outer paint set the division joint. The spacing is 1400.

10. The thickness of the exterior wall paint leveling putty is not more than 1mm.

11. If the outer wall is made of face bricks, the face brick caulking is pressed and squeezed to the compaction.

12. The drainage slope of the window sill, window eyebrow, balcony, awning, waist line and provocation is not less than 2%. The drip line should be dense and straight, and there should be no climbing or drainage.

13. When the outer wall of the upper brick is scraped with waterproof mortar, when the wall around the door and window is rough, the bottom of the wall of the door and window must be staggered.

Fourth, reinforced concrete cast-in-place plate crack prevention measures

Reinforcing ribs shall be set around the bumps of the building. The thickness of the floor slab shall be less than 120mm, and the kitchen and bathroom slabs shall not be less than 90 mm. Double-layer steel mesh shall be set for the floor slabs at both ends of the roof and standard floors, and the ribs shall be set at the corners of the outer wall. Set a post-casting strip with a width of 800 in the middle of each 11~12 axis. After pouring the pouring time, wait for 40 days after the floor is poured.

For construction, the post-casting belt 砼 strength level should be greater than the floor 砼 strength level, and infiltrated into the expanded cement.

Fourth, the technical measures to prevent leakage of doors and windows

1. Before the installation of aluminum alloy doors and windows, three performance witness sampling tests shall be carried out. After the installation, the quality supervision station shall be entrusted to conduct on-site inspection.

2. Before the doors and windows are installed and fixed, the size of the reserved wall holes should be checked and scraped with waterproof mortar.

3, door and window installation should be clean and dry, apply foaming agent, foaming agent should be continuously applied, timely check whether the blowing agent is continuous and intact.

V. Technical measures for roof leakage prevention

1. The rigid roofing layer is made of 40 thick C20 fine stone concrete, equipped with 4@150 two-way, the roof is 20 wide for every ≤3m, and the wall of the parapet is set at 200 from the wall.

2. Extend a reinforced concrete waterproof ring together with the roof structure around the roof of the well.

3. The waterproof layer of the coiled material is fixed in the groove of the daughter wall. The ends are fixed with metal strips with anti-corrosion wood strips, the nail distance shall not be greater than 450mm, and the upper and lower mouths shall be sealed with sealing material.

4. When constructing the waterproof layer or gas barrier of each roof, the structure extending from the roof pipe, the hoistway and the roof is covered with flexible waterproof material for flooding, the height is not less than 250mm; the last flooding material should be coiled. And use a pipe clamp or bead to press the upper end of the coil and seal it with a sealing material.

5. When pouring concrete, firstly lay two-thirds of the thickness of concrete and flatten the beach, then place the steel mesh, and then lay a third of the concrete, vibrate and compact, and collect the water twice.

6. The joints shall be penetrated up and down. There shall be no cement mortar bonding in the joints. After the joints and surrounding gaps are clean and dry, they shall be treated with cold base oil matched with the sealing material, and the surface shall be filled with water immediately after drying. The ointment is then attached to the SBS modified asphalt coil of not less than 200 wide centering on the divisional slit, and the four peripherals are wound up to the upper bead to close the mouth.

7, water conservation and maintenance is not less than 14d, by a special person.

8. After the construction of the roof waterproofing layer is completed, conduct a water storage or a watering test.

Sixth, indoor elevation and geometric size control measures

1. Measured by on-site construction workers, strictly control the error range according to the standard when copying and unwinding, check frequently in the process of supporting the mold, strictly control the verticality, re-measure the size before pouring concrete, the size is qualified and reported to the inspection and acceptance. Can be poured.

2. The decoration stage should be strictly in accordance with the elevation and axis control lines that are popped up.

3. According to the inspection batch, the indoor elevation and the thickness of the floor slab of the building shall be measured. Each three floors shall be an inspection lot. After the measurement, carefully fill in the "Building Indoor Elevation, Axis, Floor Thickness Measurement Record".

4. The number of indoor elevations and axis positions is checked. Each inspection lot is checked by 10% of the number of rooms and not less than 5 rooms.

5. Strictly control the thickness of the cast-in-place plate. Before the pouring, the control mark of the thickness of the cast-in-place plate should be made, and one place should be set every 1.5~2m. Floor inspection height The number of inspections per floor slab, each inspection lot is based on 10% of the number of floors and not less than 5 pieces for spot check.