Reshoring and backshoring are the processes of providing temporary vertical support shores for the stripped structural elements which have not yet developed full design strength. They also provide temporary vertical support for the completed structure after the original shoring support has been removed. Reshoring and backshoring are the two methods used to provide the concrete with support until it reaches its full design strength.
Reshores are shores placed snugly under a stripped concrete slab or structural member after the original forms and shores have been removed from a large area. In reshoring, the concrete slab is allowed to deflect and, thus, formwork can be removed from a large area. This can help reduce stripping costs, which is the main advantage of reshores.
Backshores are shores placed snugly under a stripped concrete slab or structural member after the original forms and shores have been removed from a small area. In backshoring, formwork is removed from a small area of slab and then backshores are provided. Concrete slabs or other structural elements are not allowed to deflect, and as a result, stripping can be accomplished at an earlier concrete curing age.
Reshores and backshores can be removed after the supported slab or member has attained sufficient strength to support all loads
transferred to it. Removal of reshores or backshores must be carried out with care to avoid subjecting the structure to impact loads.