Splice Coupler Placement During Installation
An issue that can affect both experienced and inexperienced installers during the repair of unbonded tendons is related to the placement of splice couplers (SC1 Splice Coupler, SC2 Splice Coupler) in a way that places high bending stress on the hardware.
These parts are designed to handle high tension loads that run in an in-line unidirectional manner through the part, and when subjected to off-center excentric tension loads, it can result in a sudden and catastrophic failure of the splice coupler.
Placement Within A Lateral Tendon Sweep
This problem occurs during the repair of tendons that have ruptured from a slab as the result of insufficient hairpin reinforcement. Some installers find it tempting to make the repair within the existing damaged area of the slab, where the tendons are making a lateral directional change.
It is strongly recommended to avoid the installation of splices within an area of lateral tendon displacement, instead they should be located in areas where the tendons have returned to a straight configuration.
Insufficient Clearance Around The Splice Coupler
This issue can develop when splices are installed in a location that causes an out of alignment condition because the splice is prevented from remaining straight due to a hardened obstacle, such as embedded rebar or concrete.
During tensioning, the obstacle can cause a high bending stress to develop within the splice coupler, resulting in failure of the hardware. Care should be given to either removing the obstacle or relocating the splice to a location where it can remain in a straight and flat configuration.
