Load Bearing Elements
Load Bearing Elements (LBEs), also known as Barrettes, are used as a deep foundation solution when high loads need to be transferred to deeper geotechnical formations. LBEs utilize the same installation methods and equipment as those used for Diaphragm or Slurry Walls. Excavations are performed under support fluid (Bentonite or Polymer), followed by installation of rebar cages and concrete placement using the tremie method. Element depths of up to 400 feet can be achieved, and the possible embedment into competent bedrock ensures the transfer of exceptionally high loads. Available low-headroom equipment can operate under 20 feet of headroom while still achieving depths of up to 200 feet.
Single LBE elements are typically rectangular, measuring up to 10 feet long and 6 feet wide, providing a substantial cross section capable of resisting and transferring very heavy vertical as well as lateral loads. Element orientation can be varied, so that multiple elements form an L, T, H, or even X shape configuration to optimize load transfer efficiently. These elements can offer a more cost-effective solution compared to drilled shafts, particularly when the equipment can also be utilized for shoring wall installation on the same project.