The beam-side anchoring curtain wall keel steel connecting piece is bolted to the steel structure, allowing for the installation of the steel beam and steel components, while also providing a welding point for securing the curtain wall keel. In the new bathroom renovation, the original precast round hole slab is removed, and a cast-in-place concrete slab is installed instead. The ends of the concrete beam at the bottom are supported by steel ox legs, which are fixed to the original precast concrete beam using plastic anchor bolts. To increase the load capacity on the concrete beam, steel legs are placed at both ends to provide additional support. The extended steel ox leg is then fixed to the original concrete stud using rubber anchor bolts.
In China, plastic anchor bolt technology is commonly used for equipment foundation anchoring, small-diameter external lighting structures, and adhesive steel plate reinforcement. This method is particularly effective for structural renovations and expansions. The series of plastic anchor bolts offer several advantages: they use plastic foil packaging with glue that is durable, easy to transport, and has accurate specifications. Rubber anchors have a long service life, and the bonding machine is multi-functional, efficient, and suitable for various applications. These anchors provide high bonding strength, quick setting after installation, and can handle heavy and vibrating loads. They do not crush concrete, require minimal drilling, cause less damage to the base, and are ideal for tight spaces—especially in old building renovations. They perform well in humid environments and meet international standards for mechanical, fire, and aging resistance. They are environmentally friendly, odorless, and safe.
To ensure reliable bond strength, on-site destructive tests are conducted under similar conditions, following relevant specifications. The maximum pull-out force must be no less than 4.5 times the safety pull force. Under this load, the glue and bolt, as well as the glue and concrete, should not separate or slip excessively. Before installation, the surface of the original concrete structure is inspected, and any necessary chiseling and repair work is completed based on the adjustment plan. Control lines for the axis, elevation, and hole center are marked out. A working platform is set up and inspected by the safety department before construction begins. A sample test is performed first to determine process parameters, and after technical and quality reviews, detailed technical and safety instructions are provided to workers before large-scale construction starts. Construction is not recommended during rainy weather or when wind speed exceeds level 5.
The construction process includes site cleaning, marking the drilling center line, detecting rebar positions, re-determining hole positions, drilling, cleaning the holes, applying the glue, inserting the anchor bolts, curing, installing the steel plates, welding the steel shanks, tightening the bolts, and spot welding before proceeding to the next step.
Survey, measurement, and development plans are crucial. Prefabricated frame columns and beam joints are often cast on-site, resulting in uneven surfaces and significant dimensional deviations. Drilling directly on such surfaces can lead to issues like misalignment of steel plates or insufficient anchor bolt embedment. Additionally, differences in precision and tolerance between the original prefabricated structure and the new one can create challenges, especially at connection points.
According to the adjustment plan, the concrete surface at the structural joint is treated, and the axis and elevation control lines are marked. Reinforced concrete beams, columns, and beam-column joints typically have densely arranged rebars. To avoid damaging main stress-reinforcing bars, a rebar detector is used to locate the actual rebar positions at the anchor points. The final drilling location is determined by considering factors such as the presence of main rebars, spacing between bolts, and margins from the edge of the concrete member. If a main rebar is located at the hole position, it must be avoided, and an appropriate gap between surrounding rebars is identified using the detector. The minimum spacing and margin are determined based on the supplier’s parameter list.
The inner surface of the drilled hole is roughened to improve adhesion between the concrete and the bonding agent, but excessive vibration may reduce concrete strength between holes. Using a diamond drill creates non-destructive holes with smoother walls, which may reduce the bonding effect between the glue and the hole wall. Therefore, if no rebars are present, an impact drill can be used directly. If a stirrup needs to be cut or an unimportant rebar cannot be avoided, approval from the designer is required, and a diamond drill should be used. Regardless of the drilling method, the hole diameter must match the anchor and glue requirements, and the depth must be strictly controlled using a measuring scale to avoid affecting the tensile strength of the anchor. When drilling, the drilling machine should be supported by a bracket, especially for horizontal holes in vertical planes, where measures must be taken to ensure the hole’s centerline is perpendicular to the plane.
Aluminum Fan Blades,Axial Fan Impeller,Fan Blades For Crane,Diesel Engine Cooling Fan Blades
Changzhou Keyleader Fan Technology Co. Ltd. , https://www.keyleaderfan.com