What are the core precautions in the installation process of Wall-Tie Bolt?

What are the core precautions in the installation process of Wall-Tie Bolt?

The installation quality of the Wall-Tie Bolt directly affects the stability of the formwork and the waterproof effect of the wall,and it is necessary to focus on the four cores of"accurate positioning,solid connection,reliable waterproofing,and adaptation to the scene"to avoid hidden dangers such as mold burst and leakage caused by installation deviations.1.Before installation:make basic preparation and selection verification Check the compatibility of specifications and scenarios:According to the thickness of the wall(such as 400-450mm long screws for 200mm thick walls)and the pressure on the concrete side(3m high shear walls require screws ofΦ14 and above),confirm that the diameter,length,and waterstop configuration(waterproof walls must have waterstops,non-waterproof walls can be omitted)are in line with the construction plan to avoid using small screws for heavy load scenarios.Cleaning and inspecting components:check that the screw is not rusted(rust depth≤0.5mm),the screw is free of slip wire,the waterstop is fully welded without leakage,and the mountain card and nut are not deformed;clean the mortar and oil stains on the surface of the screw and the plastic casing(for recyclable screws)to ensure smooth installation.2.During installation:control the key to positioning,connection and waterproofing Precise positioning,control spacing and arrangement:according to the design spacing(usually 300-600mm horizontally,400-600mm longitudinally),the screw should be perpendicular to the surface of the formwork,with a deviation of≤2°;the spacing should be reduced by 20%-30%(such as the original 600mm to 450mm)to prevent local formwork deformation.Ensure that the waterstop(waterproof wall)is installed compliantly:the waterstop should be centered and fixed in the middle of the screw(corresponding to the center line of the wall),with a deviation of≤10mm;the welding area should be checked with a small hammer,there are no false welds,porosity,and water seepage test should be done if necessary to avoid leakage caused by the offset of the waterstop or welding defects.Standardized connection to ensure fastness:When threading the screw,first put on the plastic casing(recyclable type),then pass through the formwork and keel,and install the washer,mountain card and nut on the outside in turn;Tighten the nut with a wrench to ensure that the mountain clip is close to the keel,and the torque is controlled at 30-50N·m(to avoid slurry leakage caused by over-loosening and over-tightening of the fracturing formwork).Avoid the risk of slurry leakage:The contact between the formwork and the screw should be pasted with sponge strips or rubber sealing rings,especially when the wall thickness is large(>300mm),an intermediate support(such as a steel pipe bracket)can be added to the middle of the screw to prevent the screw from bending and causing the formwork gap to be too large;check the formwork joints before pouring to ensure that there are no gaps around the screw.3.After installation:timely inspection and dynamic adjustment Comprehensive inspection to eliminate hidden dangers:After installation,use a tape measure to check the spacing and verticality of the screws,and check the flatness of the formwork with a level;manually shake the screw to confirm that there is no looseness,and there is no displacement of the mountain card or nut;the waterproof wall needs to focus on checking the position of the waterstop,marking the abnormal parts and rectifying them.Dynamic monitoring during pouring:When concrete is poured,arrange a special person to patrol,and if grout leakage is found around the screw,seal it with mortar in time;if the formwork bulges,it is necessary to reinforce the corresponding part of the screw(tighten the nut or add an auxiliary screw)to avoid the expansion of the problem.4.Special scenarios:targeted prevention and control Winter construction:The contact between the screw and the formwork should be insulated to avoid low temperature causing concrete to stick to the screw;clean the ice and snow on the surface of the formwork before installation to prevent the screw positioning from shifting.Coastal/high-water areas:Prefer hot-dip galvanized screws(anti-rust),increase the thickness of the waterstop to 3mm,and apply anti-corrosion coating at both ends of the screw after installation to enhance corrosion resistance.Following the above precautions can ensure that the installation of through-Wall-Tie Bolt meets the requirements of the"Construction Quality Acceptance Code for Concrete Structure Engineering"(GB50204),and ensure the safety of formwork support and wall waterproof performance from the source.