Analysis of the core components and functions of the wall through screw

Analysis of the core components and functions of the wall through screw

As a key component of building formwork support and waterproof wall construction,the structural design of the wall screw revolves around the three core requirements of"load transfer","waterproof sealing"and"installation and adjustment",which is mainly composed of five core parts,and the functions of each component are coordinated to ensure that the formwork is stable and the wall is leak-free during concrete pouring,as follows:

1.Screw body

The main body of the screw is the core stressed component,usually made of Q235 or 45 round bar,and the surface is mostly full or half wire structure(thread specifications are mostly M12-M16).Its core function is to withstand the extrusion force of the outer reinforcement of the formwork,resist the side pressure generated during concrete pouring,and prevent the formwork from deforming or bursting.According to different usage scenarios,the length of the screw body needs to match the wall thickness(for example,a 200mm thick wall corresponds to a 400-450mm long screw),and the diameter needs to be calculated according to the side pressure(for example,aΦ14 screw is commonly used for a 3m high shear wall).

2.Waterstop(for waterproof scenes)

The waterstop is a special component of waterproof walls(such as basement exterior walls,pool walls),mostly round or square galvanized steel plates(thickness 2-3mm,diameter≥50mm),fixed in the middle of the screw body(corresponding to the center line of the wall)by full welding.Its function is to block the penetration of water inside the concrete along the gap between the screw and the concrete,forming a"water-stop barrier"-when the water touches the waterstop,it will not be able to continue to penetrate due to the change of path,avoiding the hidden danger of leakage in the wall.Through-wall screws for non-waterproof scenarios(e.g.normal interior walls)can omit the waterstop.

3.Mountain card(butterfly buckle)

The mountain card is a key accessory connecting the screw and the formwork keel,and the material is mostly Q235 steel plate stamping and forming,which is in the shape of a"mountain"or"butterfly".During installation,the mountain snap is stuck on the screw,and the two sides are close to the wooden or steel pipe keel on the outside of the formwork,and after tightening through the nut,the keel and the formwork are firmly fixed on the screw to ensure the fastening between the formwork and the screw,and prevent the formwork from displacement during pouring.Its advantages are large contact area,strong clamping force,and can evenly transmit the binding force of the screw to the keel.

4.Fastening nuts

The fastening nut matches the thread of the main body of the screw(mostly hexagonal nuts),the material is Q235 or No.45 steel,and the surface is often galvanized and anti-rust.Its function is to tighten the mountain card,keel,and template tightly through tightening action to lock the stress state of the screw.During installation,it is necessary to use a flat washer(to enhance the contact area between the nut and the mountain card to prevent the nut from falling into the mountain card),and in some heavy load scenarios,double nuts(anti-loosening)are also required to avoid loosening the nut due to vibration during the pouring process.

5.Plastic casing(special for recyclable screws)

Plastic casing(mostly made of PP or PVC)is only used for recyclable wall threads(such as three-stage screws),which are sleeved on the outside of the main body of the screw and the length is the same as the thickness of the wall.Its function is that after the concrete is poured,when the screw is removed,the casing remains in the concrete,forming a reserved hole(subsequently sealed with mortar),so that the main body of the screw can be reused and reduce material waste.At the same time,the casing can also avoid the direct adhesion between the screw and the concrete,reducing the difficulty of removal.

The above five parts work together to form a complete functional system of the wall screw-the main body of the screw is stressed,the waterstop is waterproof,the mountain card and nut are fastened,and the plastic casing is recycled,ensuring safety and practicality in different construction scenarios.