Triangular cross section support frame, especially for tunnel construction, has welded design with three parallel rods linked by two zigzag wire profiles and cross braces

摘要

A triangular cross section support frame, especially for tunnel construction, comprises three parallel rods, with one rod uppermost and two at the base corners of the triangle and linked by two zigzag wire profiles (3) between the lower and upper rods and with cross braces between the lower rods. The rods and zigzag profiles are secured by weld sites to provide a lightweight frame with high load capability.