A pipe brace assembly includes a main clamp body that can be secured to a brace pipe. A cable, or other flexible tensioning member, can be wrapped around a braced pipe and secured to the main clamp body. The pipe brace assembly includes a method or mechanism for tensioning the cable or flexible tensioning member around the braced pipe. In some embodiments, the tensioning method or mechanism involves moving, such as rotating, the main clamp body to tension the cable or tensioning member. The clamping of the main clamp body and tensioning of the cable or tensioning member can occur simultaneously.