Strengthening an existing concrete structure through the use of shear dowels is a primary application of post-installed rebar. Though this is commonly done to improve the performance of concrete slabs and structures experiencing earthquake and seismic loads, the application is not limited to geographic areas experiencing these conditions. Shear dowels are typically used to resist interface shear across a shear plane – the roughened joint between existing and new concrete. The primary shear mechanism – friction across the irregular surface – is enabled by the shear dowels that hold the surfaces together. Therefore, the standard design assumption is that the shear dowels are placed in direct tension as the irregular shear plane is translated laterally.
Reference the Post-Installed Reinforcing Bar Guide for comprehensive design information on post-installed rebar theory, design and installation. Additionally, you will find ICC ESR-3187 for the HIT-HY 200 hybrid adhesive anchor system and ICC ESR-3814 for the HIT-RE 500 V3 epoxy adhesive anchor system on our Approvals and Reports page.