Tiebacks may be used in conjunction with a variety of retaining systems (sheet piles, soldier piles, and underpinning) to provide additional lateral resistance beyond that achievable by a cantilevered wall. Tiebacks are drilled into the ground with a small diameter shaft. They can be horizontal but are typically installed at an angle of 15 to 45 degrees. The tiebacks are constructed of thread bar or steel strands which is inserted into the small drilled excavation. The shaft is grouted which encases the steel and bonds it to the surrounding ground. The steel is stressed to a design load and locked-off to maintain the load on the tie-back. Tie-backs can be installed in one or multiple rows as required to support the excavation depth.