DOWEL BAR RETROFIT IN PORTLAND CEMENT CONCRETE PAVEMENT

Load transfer restoration (LTR) increases the load transfer capability of existing jointed plain concrete pavement (JPCP) and jointed reinforced concrete pavement (JRCP). Load transfer is the ability of a joint or crack in a concrete pavement to transfer load from one slab to the neighboring slab through shear action. The greater the load transfer efficiency, the better the pavement's performance. LTR increases the pavement's load transfer efficiency by placing a mechanical device, (e.g., a dowel bar) across joints or cracks that exhibit poor load transfer. Up until the 1990s, the two most common practices used to fix roughness and faulting were asphalt overlays and diamond grinding. The potential problem with these remedies is that they cover up or remove the faulting, but do not address the problem of poor load transfer at the joints and cracks. Unless the issue of load transfer is addressed, joint faulting can recur shortly after these remedies are completed. Recent improvements in the field of concrete pavement restoration (CPR) now better address the problem of poor load transfer. Dowel bar retrofit is a LTR technique used to increase the load transfer capability of existing jointed concrete pavement by placement of dowel bars across existing joints and/or cracks that exhibit poor load transfer. When used in conjunction with diamond grinding, it increases the load transfer capability and structural capacity of the pavement and removes its roughness.