Cracking in walls with combined base and end restraint

Abstract

Restraint of early-age thermal and long-term shrinkage strain can cause cracking in reinforced-concrete members. Eurocode 2 provides guidance on the design of crack control reinforcement in reinforced-concrete elements with base (edge) and end restraint, but not combined base and end restraint, which commonly occurs. The paper describes an experimental programme, which was conducted to investigate early-age and long-term shrinkage cracking in reinforced-concrete walls with combined base and end restraint. The main variables in the test programme were concrete cover and reinforcement ratio. Early-age cracking is simulated with non-linear finite-element analysis, which is shown to capture the observed behaviour adequately. Eurocode 2 gives reasonable estimates of long-term crack widths in the tested walls if edge restraint is assumed, but significantly overestimates crack widths if the worst case of end restraint is assumed.