There are three types of drill bits used on self drilling anchor bar. The highly versatile carbide cross cut bits, carbide button bits for hard rock and stepped clay bits for cohesive clay. The type of drill bit and size is based on the soil type and the desired capacities. Larger boreholes provide higher load carrying capacities and more grout cover. The grout cover protects the anchor bar from corrosion but galvanization is also available. Production rates are higher when using hollow anchor bolt systems as compared to traditional drilled anchors. This is especially true when drilling at sites with low headroom or where there is the risk of bore hole collapse.
Sinorock stands ready to support you during the design, planning and construction of your project. The spacing, inclination, length and the load applied of each anchor depend on the local soil or rock conditions. The available drilling equipment and the structural capacity of the other support elements, such as wales, lagging or a concrete retaining wall, may dictate the capacity and configuration of anchors. A factor of safety of 1.5 to 2.5 should be utilized in anchor design.
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