Estimation of bond strength envelopes for old-to-new concrete interfaces based on a cylinder splitting test

The number of existing structures under rehabilitation has significantly increased over the past two decades; these structures typically require performance improvements including repair and strengthening. Currently, reinforced concrete is widely used in interventions for the rehabilitation of bridges and buildings. Here, we present a method for the estimation of failure envelopes for old-to-new concrete interfaces based on plasticity theory. The proposed Carol-type failure envelope uses the simple splitting tension test, also known as the Brazilian test. The relevant parameters of the envelope— f t ′ , the tensile strength, c′, cohesion and ϕ′, the friction angle—are assessed by experimentation, a rational formulation and a bibliographic study, respectively.