(1) Anchor spray support 1. Construction of bolt support The anchoring method mainly includes resin (powder type) bonding, cement (powder type) or cement mortar bonding, and mechanical friction type. According to the length of the anchor, it can be divided into full-length anchor or end anchor. 2, shotcrete support The shotcrete strength grade is mostly C15-C20. As a separate support structure, the thickness of the spray layer is generally about 15 cm, and the joint of the anchor spray can be 5-10 cm. In order to strengthen the bearing capacity of the spray layer, the steel mesh can be laid and become the joint support of the anchor, spray and net; for the anti-deformation ability of the sprayed concrete, the measures of adding steel fiber in the sprayed concrete can also be adopted. In order to reduce rebound and dust, shotcrete should also have admixtures. At present, the most commonly used in China is the quick-setting agent. The general dosage is 2.5%-4% of the cement dosage. It requires the concrete to be condensed for 3-5min and the final condensation for 10min. 3, anchor support Bolting is the support of the shotcrete support on the basis of the original gold or metal stent, the retaining Lining basis, or after grouting surrounding rock. On the one hand, the loosely broken surrounding rock can be cemented into one piece; on the other hand, the common end anchor bolt can be fully anchored. (2) Lining (碹) and fabricated concrete large arc support 1. Lining is a passive and passive support. It is generally believed that the lining structure is a rigid support. 2, lining is generally used as a permanent support, can also be used in conjunction with temporary support such as anchor spray. 3. When the pressure of the top and bottom plates is large, it is more reasonable to use the horseshoe arch. (three) bracket support 1. Trapezoidal metal bracket: It is usually made of 18-24kg/m rail, 16-20 I-beam or mine I-beam, composed of two legs and one beam. Usually used in the mining roadway. 2, arched shrinkable metal bracket Repeated use, suitable for roadway with large ground pressure, unstable ground pressure and large deformation of surrounding rock. (4) Anchor support Prestressing the surrounding rock is an active support. Anchor cables are often made of high-strength steel bars, steel strands, and high-strength steel wire materials. They are usually anchored with cement mortar, and resin anchoring agents can also be used. Ungrouped fasteners Ningbo Brightfast Machinery Industry Trade Co.,Ltd , https://www.brightfastener.com