Common problems: the formwork has too large sill and joint, which affects the forming appearance and quality prevention: (1) install in strict accordance with the number; (2) Repair the deformed formwork · common problem: serious damage to the line and falling slab edge concrete during formwork removal prevention: use special formwork removal tools and control the formwork removal time according to the temperature · common problem: the laitance on the formwork surface is not cleaned, which directly affects the splicing size and forming appearance of the formwork.
Prevention and treatment: clean it every time after the formwork is removed, Clean the laitance on the formwork surface, apply release agent before assembly ➣ aluminum formwork construction effect drip line masonry tongue and groove stair opening lintel internal and external corner wallboard (source: integrated in the network, the picture and copyright belong to the original author, if there is infringement, please contact to delete!) Long press the QR code to follow us ▶▶▶。.
In order to prevent excessive oil from flowing and polluting the ground, only the upper half of the formwork shall be painted, and the lower half shall be allowed to flow freely and evenly; (3) The release agent of the floor part can not be painted by roller, but can only be sprayed by glue pot, and the amount can not be too much ➣ the removal of aluminum formwork system.
This paper shares the application of aluminum formwork in the engineering example of China Construction Third Engineering Bureau, and introduces the construction technology for reference to engineering friends.
Let’s come to the construction site and take a look at the installation and removal of aluminum formwork ▼➣ selection requirements of aluminum formwork project · floor height give priority to aluminum alloy formwork.
Installation requirements of starting plate (1) the embedded screws of starting plate of outer wall must be embedded firmly in the lower concrete in advance, the spacing between two screws shall not exceed 1200mm, and the single plate shall not be less than 2; (2) In addition to the embedded screws, there is also a row of wall screw rods under it to prevent the balance and stability of starting.
➣ deepen the design, deepen the design of aluminum mold assembly drawing according to the architectural drawing, and review and approve the design plan, template processing drawing, template assembly drawing node detail drawing by the owner / Design Institute ➣ produce and manufacture aluminum mold, make profile blanking, punching and welding semi-finished products in the factory, QC check and clean aluminum mold products ➣ trial assembly, trial assembly of aluminum mold in the factory, It shall be pre accepted and adjusted by the owner / Design Institute / Supervisor in the factory ➣ the transportation system number, disassembly and packaging shall be transported to the site, Site handover ➣ installation site assembly and acceptance ➣ removal and reuse ➣ good concrete surface effect.
The application floor height is 2.8-3.2m, more than 3.2m, The traditional support method shall be adopted, and the combination of cross bar, cross bridging, external frame aluminum formwork and external climbing frame is the best construction method.
Common problems: prevention of plane dislocation caused by non drilling of pins: (1) all pins on the wall formwork must be filled according to the hole position requirements; (2) Two components shall be connected, and at least two pins shall be provided; (3) The spacing between two pins shall not exceed 300mm.
Multiple buildings with the same type of structure have been used for more than 30 times in total ➣ composition of aluminum formwork system · formwork system · accessory system pin, pin piece long pin, pin piece cup head, rubber hose pull screw, gasket K-plate screw · support system · fastening system, diagonal hoist tie back ridge · material transfer hole ➣ installation and installation process of aluminum formwork system.
After the strength meets the requirements in the above table, it can be removed after it is reported to the supervising engineer for approval· Remove the floor formwork · remove the beam bottom formwork ➣ prevention and treatment of common quality problems of aluminum formwork construction · common problems: the formwork is not passivated before use, and a large number of bubbles and cavities are generated on the concrete forming surface.
Requirements for painting release agent (1) all formwork must be cleaned before painting formwork oil; (2) After the wall formwork is firmly erected, the roller shall be used to brush oil.
Sequence of aluminum formwork going upstairs when used: wall body plate, beam plate, floor plate Support and others; All formworks shall be installed according to the drawings and numbers, and shall not be installed incorrectly or omitted.
In order to ensure the concrete quality, three groups of the same curing cube test blocks shall be added during the concrete pouring construction.
If the outer frame is a cantilever frame, it needs special treatment in formwork design, manufacturing and on-site installation, with high cost, increased construction difficulty, optimal structural form of shear wall structure and frame shear structure, more masonry walls of other structures, no obvious advantages of using aluminum formwork, few outline lines of outline structure and complex changes, and a comprehensive economic single building is used for about 30 times, That is, buildings with more than 30 floors are used for the first time.
Before removing the bottom formwork of aluminum alloy formwork, the concrete strength shall meet the requirements of the list.
Wall body plate installation ↓ beam plate installation ↓ flat plate installation ↓ upright support ↓ diagonal brace installation ➣ treatment of key and difficult points · upper limit reinforcement shall be planted around the wall column formwork at the lower opening of shear wall, and wall thickness positioning reinforcement shall be welded on the reinforcement; Install the positioning rubber plug and hard finished PVC pipe at the place of the pull screw · reinforce the door opening where deviation is easy to occur, and add a back edge at the upper and lower parts of the door opening for reinforcement · internal corner treatment.
Prevention and control: (1) strictly control the elevation of the slab surface; (2) Sealing with dry and hard mortar.
According to the engineering experience, the time profile of formwork at each part is as follows: the wall column formwork can be removed in about 24 hours, the beam side formwork can be removed in about 36 hours, and the beam bottom can be removed in about 48 hours The plate bottom formwork (non bearing) shall be removed in about 12 days, the plate bottom bearing pillar shall be removed in about 14 days, the beam bottom bearing pillar shall be removed in about 28 days, and the specific removal time of each part shall still be determined according to the strength· Precautions for aluminum formwork removal: 1.
The pressure test of the test block shall be carried out before the bottom formwork is removed, or the rebound instrument shall be carried out on site.
The perpendicularity deviation is mostly found in the internal corner, The main bullet pins and fixing bolts in this part are strictly required to have no less than 2 screws on one side of each single formwork and the spacing shall not exceed 300mm.
Architectural communication media ID: jianzhong001 has been widely used in construction projects before.
Common problems: the wrong sealing method of the lower opening of the formwork causes column breakage or slurry leakage at the column root.
Prevention and treatment: the aluminum formwork contact concrete surface is painted with 1:3 cement mortar for 2 ~ 3 times in the factory or on site, Make the formwork surface fully passivated.
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Generally speaking, the implementation process of aluminum formwork includes: deepening design → production and fabrication → trial assembly → transportation → installation → removal.
