Underground Mining Bolts and Support Systems Quiz

Types of Bolts and Support Systems in Underground Mining

• The video discusses the different types of bolts used in underground mining and the factors that determine their suitability.
• Factors include the presence of water, expected duration of fortification, criticality of operation, and properties of the rock.
• Different types of bolts include resin, cement, and expansion bolts that rely on friction with low contact loads.
• Anchor bolts are made of steel and are designed to stick to the rock mass using either resin or cement grout.
• The installation process involves inserting the resin cartridges, followed by the bolt, which is rotated to ensure a homogenous mix with the included catalyst.
• Limitations of using resin bolts include sensitivity to moisture and acidic drainage, limited durability of the resin, and potential danger of manipulating the resin.
• Cement grouted bolts have a longer lifespan than resin bolts but have lower adherence and work more slowly.
• Steel cables may be used for anchoring in situations where bolt length exceeds 6 meters.
• Friction bolts with high contact loads that are mechanically anchored include expansion bolts, which are complicated to install, have limitations, and cannot be used in hard rock or water.
• The four fundamental parts of an expansion head bolt are the bolt itself, the metal plate, the distribution plate, and the nut that anchors the bolt to the terrain.
• The versatility of bolts lies in the type of resin and cement used, but a mix between the two types of bolts is never recommended.
• It is important to carefully choose the appropriate bolts based on the equipment and rock conditions to ensure optimal support capabilities.