The most common vehicle restraint installation is to lag bolt the vehicle restraint to the face of the poured concrete foundation wall. The vehicle restraint is centered on the dock leveler/overhead door width, positioned at grade level tight to the foundation wall. The vehicle restraint is then lag bolted into position; only use the anchor bolts and quantity that are specified by the vehicle restraint manufacturer. This link shows a typical installation. https://www.pentalift.com/wp-content/uploads/2021/04/RVR32-Brochure.pdf
Most loading dock areas have a level approach. In an application with a declining approach at the loading dock area it is common to project the dock leveler pit and dock leveler bumpers out from the foundation wall. Projecting the pit and dock bumpers out prevents the top of the incoming vehicles from contacting the building wall above the overhead door. This link shows a projected pit. https://www.pentalift.com/wp-content/uploads/2020/11/Projected-Pit-Dock-leveler-Benefits-1.pdf
Many projected pits are formed and poured down to grade level. In this case the vehicle restraint is installed on a flat vertical concrete surface. The projected pit shown above is not poured down to grade level. To install a vehicle restraint with these site conditions it is common to order a steel extension plate manufactured to the height and depth of the space under the projected pit. The extension is first lagged to the face of the foundation providing a full depth flat vertical surface to install the vehicle restraint.
Although this is a common procedure the integrity of the installation could be compromised. Based on the model of vehicle restraint there could be up to 3 vertical rows of 5 lag bolts per row. Lag bolts that are drilled just above the steel extension could crack the concrete on the bottom of the projected pit providing little or no anchoring support resulting in a loss of 20% of the total installation integrity.
If the site has a concrete pad with sufficient depth and strength poured underneath the required location of the vehicle restraint the recommended method of installation for a partial height extended pit is a surface mount vehicle restraint.
The surface mount alternative is available in any model of Pentalift vehicle restraint that is normally lag bolted to the concrete foundation wall. The HFR32SM restraint is the most cost effective choice for surface mounting installation.
https://www.pentalift.com/wp-content/uploads/2020/11/HFR32SM-only-SM.pdf   A surface mount vehicle restraint is the recommended method of installation for any foundation that has either deteriorated or is not rated to withstand the draw bar forces on the vehicle restraint. Surface mount is also the recommended method of installation for any free standing dock leveler installation.
For additional information on Pentalift vehicle restraints or any other Pentalift products please contact the Sales Department.