Lightweight partition board has been widely used in construction projects, and has many advantages: light weight, high strength, good impact resistance, waterproof, sound insulation, heat insulation and other excellent properties; The surface is flat, the size is accurate and neat, which is convenient for mechanized production and has high production efficiency; Large size, good integrity, and prefabricated construction, high construction efficiency. But at the same time, lightweight partition panels also have a fatal quality problem: they are prone to cracks! What are the causes of installation cracks? And how to prevent it?
1. There is a problem with raw materials
1. Wall panel material
[Problem]
There are cracks and damages in the wallboard material, as shown in the following figure:
Cracked or damaged wall panels
【Prevention and control measures】
(1) In the inspection stage, focus on evaluating the quality control ability of the wallboard factory, and select the fittest.
(2) The wallboard enters the site and strictly implements the five-party acceptance, and selects the yard to avoid damage.
(3) Cracked or damaged wall panels that have been transported to the building are not allowed to be put on the wall and must be removed once found.
2 Mortar material
[Problem]
The special mortar is unqualified or cracks occur when the floor mortar is used, as shown in the following figure:
The special mortar is unqualified
【Handling Measures】
(1) Test the special mortar as required, and the expired one shall not be used.
(2) The special mortar for landing shall not be on the wall to fill the notch.
Second, the early optimization is unreasonable
1. No layout or unreasonable layout
[Problem]
Cracking occurs in the non-standard board, as shown in the following figure:
Cracking of non-standard plates
【Handling Measures】
(1) The cutting surface on the left side of the figure is located in the hole part, which should be avoided in the nesting process, and the cutting position can be changed to the solid place. If such a situation cannot be avoided, the holes of the wall panel should be filled with priority during the wall paneling process.
(2) The part on the right side of the figure that connects with the structure must be full of slurry, and the steel wire mesh of the traditional plastering project must be set in place; The aluminum mold project must be left with an opening to ensure that the position of the plate seam is strengthened by the mesh treatment.
2. Optimization of the electrical box
[Problem]
The electrical box is set on the 100mm wall and cracks, as shown in the following figure:
The location of the electrical box is cracked
【Handling Measures】
(1) Choose a thin box.
(2) The design is optimized within the 200mm wall; The aluminum mold project can be optimized to be partially changed to cast-in-place.
3. Optimization of electromechanical points
[Problem]
The mechanical and electrical points of the wall panel are not fully considered, and the pre-embedding of the door buttress line pipe leads to the lap of the lintel less than 150mm, the installation of multiple wire boxes, the presence of chutes or the second slotting after omission, resulting in cracking, as shown in the following figure:
Pipeline embedded impact, multi-wire box installation
【Handling Measures】
(1) The lintel sample of the door opening in the layout must be completed; Before the construction of the cargo volume area, the layout must be adjusted in time according to the model construction.
(2) Communicate with the design that the multi-wire box is merged into multiple control panels or optimized for cast-in-place.
3. Insufficient on-site control
The site must be constructed in strict accordance with the disclosure, process and deepening drawings, and shall not be changed at will.
1. The squeezing is not full
[Problem]
Cracks appear at the top, seams and corners, door heads, etc., as shown in the following figure:
The top, the seams, the yin and yang corners, and the door head are cracked
【Handling Measures】
(1) Strengthen the control of the process to ensure that the top is full of slurry and properly maintained; Strictly control the time of withdrawal of the cork (7 days in summer and 12-14 days in winter).
(2) The installation and subcontracting of wall panels shall be tracked by professional quality inspectors; During the installation process, the project quality inspector and constructor inspect the wall panel in the installation process; Each wallboard must be fully pulped in place, and the wallboard must be slurred on the wallboard before the wallboard is installed, and the joints shall not be plugged back.
(3) Squeeze the slurry to be full, and paste the reinforced glass fiber mesh according to the requirements; The layout is reviewed as required to avoid non-standard boards.
(4) The side of the lintel must also adopt the squeezing method (PE rods need to be installed to ensure that the slurry does not leak into the hole of the wall panel) to ensure that the slurry on the side is full; The slurry plug at the lower mouth of the lintel needs to be full and dense and the second back pressure; It is recommended to design the surface layer of steel wire mesh reinforcement at the door opening.
2. The maintenance is not in place
[Problem]
Insufficient maintenance leads to insufficient strength and cracking, as shown in the following figure:
Inadequate maintenance
【Handling Measures】
The depth of the first groove filling should not be too large, and it should be controlled 3-5mm below the finished surface of the opening; The special mortar should be used within 2-3 hours after the mixing is completed; After the end of the trough repair, it should be cured for 3-4 days.
【Extended Learning】
Lightweight partition panel installation process
ALC lightweight partition panel, also known as autoclaved aerated lightweight concrete panel, is a new type of building energy-saving product. It has the advantages of light bulk density, good sound insulation and thermal insulation effect, low cost, simple installation process, low construction period requirements, production industrialization, standardization, installation industrialization, etc., and has been widely used in high-rise frame buildings and internal and external walls of industrial plants.
Characteristics of the construction method
1. The board is light in weight, small in design load, and is a good insulation and sound insulation material due to its loose and porous texture.
2. When making wall panels, the building usable area is expanded due to the thin board.
3. The ACL board material is green and environmentally friendly, with good sound insulation and fire insulation performance far exceeding the requirements of A1 level.
4. ALC lightweight partition panel is easy to install and fast to construct.
Installation process
Step 1: Plate elastic line
Step 2: Sheet cutting
Step 3: Fix the U-shaped card
Step 4: Plate installation
Step 5: Proofread the verticality
Step 6: Flatness proofreading
Step 7: Fill the mortar at the bottom joint
Step 8: Top seam foaming agent tamponade
Step 9: Plate hanging net to repair joints
Step 10: On-site grooving
Risk point control
1. Damage to transportation
| ALC lightweight partition board has low strength and is easy to be damaged during transportation and handling |
ALC lightweight partition panels stacked
ALC lightweight partition panel loading and unloading
【Handling Measures】
1) Hoisting, stacking: when lifting, it is necessary to use nylon slings (wire ropes can not be used) to be tied to 600mm at both ends of the plate, each lifting weight does not exceed 2T, and when landing, there is a piece of sleeper at 600mm at both ends of the plate, and there should be a special person to command when lifting, and the sling distance at both ends of the plate should be consistent, and the sling should be straight to ensure that both ends of the plate are off the ground and landed at the same time. In order to facilitate the transportation of plates, the number of stacking layers shall not exceed two layers when unloading, and the single layer shall be stacked when conditions permit.
2) Plate quality: do not use plates whose processes do not meet national requirements or whose ingredients and processes are unreasonable.
3) Construction management: In order to meet the construction period, the wall panel with an age of 28d should not be sent to the site for use.
4) Moisture-proof protection: Moisture-proof measures should be taken at the transportation and construction site to prevent moisture.
5) Drawing deepening: 1-2 months in advance should communicate with the interior wall panel company to deepen the drawings and friendship.
【Optimization Direction】
1) The net height of the bottom of the structural beam should be unified as much as possible to reduce the number of types and types of plates due to different heights.
2) The groove treatment at the junction between the inner wall panel and the structure is convenient for hanging the net and preventing cracking.
2. Deepening layout of the secondary structure
| There are no special-shaped plates at the corners (yin and yang corners), door buttresses and other positions, and local cast-in-place is required |
Set up the construction column
1) The length of the ceramsite board wall and the length of the ALC lightweight partition board wall are more than 6 meters and less than 12 meters, and structural columns are set in the middle.
2) Corner Door Stacks:
(1) The pins out of the corner wall and T-shaped wall must be constructed according to the drawings and connected by special repair materials for the plate.
(2) Plates less than 100m should be poured with secondary structures as far as possible.
(3) The indoor door is installed with section steel for reinforcement and installation. The door less than 1500 is shelved with plate 100, reinforced with tie bolts, the door opening greater than 1500 is hung with section steel, and the entrance door is made of reinforced concrete door frame.
3) Door opening treatment:
(1) The upper part of the door opening should be in the form of a downward hanging structural plate.
(2) Tube wells, toilets and other buildings that are often flooded should have anti-barriers.
4) The corner or T-type connection of the partition board should be fixed with φ6 pins. The position of the pin should be 300~400 from the top and bottom of the partition wall. The pin spacing is around 700. The total depth of the pin anchored into two plates in different directions shall not be less than the thickness of one plate plus 150mm.
Corner or T-shaped treatment
5) Due to the material characteristics of ALC lightweight partition panel, it is not suitable for walls below 200mm width, especially for the short limb wall and door buttress with a side of less than 200mm in this project, the door buttress adopts secondary structure construction, adopts the reinforcement planting method, and is equipped with 2 8mm threaded steel bars and fills with C25 fine stone concrete.
3. ALC lightweight partition board typesetting and slotting
| The width of the slotted incision is not limited, and the depth should not be greater than 1/3 of the plate thickness |
【Handling Measures】
1) Before the installation of ALC lightweight partition panels, the typesetting design must be carried out according to the modulus, and ALC wall panels less than 200 shall not be used.
2) In the middle of the small board, the two sides of the large board are typeset.
3) After the installation is completed, 14 days before the water and electricity slotting, use professional tools to slot, first pay-off, and then slotting.
4) After the installation of the hydropower pipeline is completed, the anti-cracking mortar repair construction is allowed at an interval of 7 days.
5) It is best not to use ALC lightweight partition wall board wall for unit sub-household wall, and it is recommended that the design institute change it.
| 4. Plate seam treatment |
Board-to-board connection points
The plate is connected to the beam
Cracked seams
【Handling Measures】
1) The mortise and tenon joints between the ALC lightweight partition board and the board are naturally occluded, and there is no extrusion and adhesive to form a deformation joint; After installation, the stability period is more than one week, and the mesh cloth must be glued to the sealing board surface decoration operation, and the alkali-resistant glass fiber mesh cloth must be bonded at the board seam to resist cracking, and the width of the mesh cloth shall not be less than 300mm, and it shall be set in the center along the plate seam. The surface decoration material should be made of elastic materials for decoration construction.
2) If there is a stucco layer, it is recommended to use gypsum mortar to paint, which has little shrinkage and reduces the risk of wall cracking.
3) Decorative plastering should be closely coordinated with water, electricity, heating, sanitation and communications, etc., and the pre-embedding and reservation of each part should be completed and inspected and accepted before it can be carried out, and it is forbidden to drill holes, drill holes and remove grooves afterwards.
4) The surface layer should be maintained in time after construction, and all collisions should be prohibited within 3 days.
5, material water absorption
| Bathroom masonry walls |
【Handling Measures】
Toilets and other parts are easy to be soaked in water, ALC materials have good water absorption, and communicate with the design institute when the ALC lightweight partition panel is deepened, and consider using solid bricks for construction.
6. Pipe clamp method construction
| Pipe clamp method construction plan |
【Handling Measures】
1) Determine the direction, consider the ceiling, etc., to prevent the exposure of iron sheets.
Diagram of the top node of pipe clamp method construction
2) When the wall is installed, it is necessary to ensure that the top slurry is compact, the lower part is plugged with a wooden wedge, and a 30mm gap is reserved at the lower mouth. After the wall is allowed to stand for at least 7 days, the wooden wedge is removed, and the bottom of the 1:3 cement mortar is filled with slurry, and no work shall be carried out on the wall during the standing period.
Diagram of the bottom node of pipe clamp method construction
7. Distribution box
| Elevation view of the distribution box |
【Handling Measures】
1) The special-shaped plate should be made for the distribution box and embedded in the special-shaped board.
2) It is strictly forbidden to slotted and bury the distribution box after the installation of the wall panel.
3) The distribution box should be embedded in the factory and reinforced; If it cannot be embedded and installed in the factory, it must be embedded and installed on the site before the wall panel is installed (on the wall).
epilogue
ALC lightweight partition board new technology from the improvement to the construction should be in-depth consideration of each process, must be systematic, comprehensive measures to solve, from the production and processing of wallboard materials and construction and installation of two aspects, and constantly solve the problem and improve the process, I believe that ALC lightweight partition board will have broad development prospects, will be gradually improved after the vigorous promotion.
Originated from丨Tengyue Construction Jiangsu Branch