On site problem 11: the waterproof of the basement roof has been constructed, and micro leakage has occurred at the bottom of the slab, forming the phenomenon of mildew in the printed water.
Treatment suggestions: strengthen the phased acceptance of reinforcement works and the side station control of concrete construction.
Field problem 02: the upper reinforcement of the double-layer two-way reinforcement of the structural slab sinks.
(when the area is large or the honeycomb is deep, a special repair plan should be prepared and implemented after being approved by the design.) Site problem 08: honeycomb and pockmarked surface are caused by mortar leakage at the column base.
Field problem 01: the reinforcement stacking and reinforcement processing of the basement roof have an impact on the concrete structure.
Cause: the formwork is removed when the lower concrete does not meet the strength requirements.
Field problem 03: after the structural column reinforcement is offset, it is bent at will, which does not meet the structural requirements.
If the formwork must be removed, the support shall be replaced at the same time, and the support shall be firm to ensure that the beams and slabs on both sides of the post cast strip are not deformed.
Cause: the joint of the coping stone of the retaining wall is not sealed tightly, the junction of the coping stone and the wall stone is not treated with closed water, and the wet paste mortar is not dense.
Cause: the construction organization arrangement of the construction unit was not reviewed and monitored in detail.
Treatment suggestions: it is best to equip three sets of formworks for the upper three floors of the floor in a month.
Cause: when pouring and tamping concrete on the floor slab, the upper reinforcement is stepped down, which has been bent or only two-way single-layer reinforcement, and the concrete slump is too large.
Field problem 05: the plain soil slope of the independent foundation does not meet the stress requirements, which is easy to cause the eccentric stress settlement of the column foundation after the bearing layer of the column foundation is damaged.
If only two sets of formworks are equipped, when the lower formwork is removed, the bottom of the slab shall be reinforced and supported with steel bars, and attention shall be paid to overload construction.
Site problem 19: the construction quality of the rigid waterproof layer of the basement roof is poor, which cannot meet the requirements of the rigid waterproof layer.
Treatment suggestions: the loose part of the concrete should be carefully chiseled to the concrete dense layer, and the concrete with higher strength than the original concrete should be poured and repaired.
When repairing, mortar is used as the repair material, and the strength does not meet the specified requirements.
Treatment suggestions: strictly control the slump of commercial concrete, ensure that the concrete is vibrated compactly when pouring and vibrating, and use a plate vibrator for secondary vibration.
Site problem 07: the concrete surface has serious slurry leakage, causing honeycomb and pitting, which affects the service life of the structure.
Site problem 06: the interlayer between the first floor slab and the foundation of the building is not backfilled, the rainwater flows and accumulates to form a puddle or pool, and the building foundation is soaked in sewage, which seriously affects the service life of the building.
If limited by conditions, the elevation of the column bottom should be adjusted or the soil should be strengthened.
Water leakage at the inner root of the outer wall of the basement.
Treatment suggestions: when pouring and tamping concrete, strictly control the damage and trampling of reinforcement.
2.
Site problem 09: the post cast strip has no support, and the upper part is being loaded for construction.
Site problem 18: the waterproofing of the basement roof coiled material is constructed on the horizontal plane, resulting in a large area of water.
If there is a two-way single-layer reinforcement, communicate with the designer about the adjustment plan; Strictly control the slump of commercial concrete.
Site problem 15: 45 degree inclined crack of cast-in-place floor slab.
Site problem 17: the concrete density of the pitched roof is poor, the water leakage treatment is not done before the construction of the leveling layer, and the leveling layer does not meet the construction requirements, resulting in serious rainwater leakage after the roof leveling.
Rainwater flows into the stone mortar layer and brings out the alkali, forming the phenomenon of efflorescence..
Cause: the construction process is not strictly controlled, and reinforcement protection is not done well when pouring concrete.
Treatment suggestions: strengthen the inspection and concealed acceptance of reinforcement binding.
Treatment suggestions: after the construction of the roof structural layer is completed, it is necessary to focus on observing whether there are leakage points, and focus on repairing the location where leakage occurs.
Field problem 12: after the membrane is removed from the pumped commercial concrete beams and slabs, small holes appear on the surface, resulting in large-area water leakage.
Complete the self waterproof reinforcement of the structure before waterproof construction.
If the overlapping part is defective, it is easy to cause the coiled material to bulge and detach, and the rainwater enters the bottom of the coiled material, which is easy to cause the basement floor to leak water or mildew.
Treatment suggestions: this place should meet the requirements of the slope distance of the bearing layer.
Treatment suggestions: after the honeycomb phenomenon occurs in the column base, the loose part of the concrete should be carefully chiseled to the concrete dense layer, and the concrete with higher strength than the original concrete should be poured and tamped for repair.
Site problem 10: the slurry leakage at the junction of the basement shear wall and the bottom plate causes honeycomb phenomenon, which is easy to form rainwater leakage points.
Site problem 16: Cracks in the cast-in-place slab of the delivered building (300 thick fire passage basement roof, C35 concrete, double-layer two-way reinforcement) and poor waterproof construction quality.
Site problem 04: there is no protective layer at the bottom of the post cast strip girder in the basement, which seriously violates the specification requirements and affects the service life of the girder.
Field problem 14: through cracks in the horizontal and vertical structural floor slabs.
Cause: before pouring and tamping the column concrete, the column reinforcement was not positioned, and the reinforcement could not be aligned with the upper column reinforcement, resulting in bending.
(the specification requires that the indoor backfill should be 200mm higher than the outdoor floor.
Treatment suggestions: when it is necessary to carry out surcharge construction on the top plate of the basement, the design load must be clearly defined, and the construction materials must be evenly stacked to avoid overload construction.
Treatment suggestions: check the positioning and binding of column reinforcement during reinforcement acceptance (spot welding can be appropriate), and carefully stand by when pouring and tamping column concrete.
There are only two sets of formwork for three floors a month.
Cause: the repair materials and methods are used incorrectly, and there is no repair plan.
Treatment suggestions: 1.
Field problem 13: the cast-in-place slab has a large area of short through cracks.
When making the formwork of the floor, try to use the separation system to make the formwork of the post cast strip and the formwork on both sides.
When removing the formwork of the floor slab, keep the post cast strip formwork and support.
Cause: there is no clear construction measures for the construction and protection of post cast strip.
The lower slab bears the weight of the upper concrete, and then a large amount of loading causes cracks in the slab.
Treatment suggestions: strictly control the slump of commercial concrete, ensure that the concrete is vibrated tightly when pouring and tamping, and focus on the process control of the watered board surface or wall surface.
On site problem 20: the stone surface on both sides of the garage ramp is wet pasted with alkali.
