Mechanical behaviour of slabs made of strain-hardening cement-based composite and steel reinforcement subject to uniaxial tensile loading

摘要

Strain-hardening cement-based composites (SHCC) are a group of high-performance materials which shows a high non-linear deformation capability and experiences strain-hardening behaviour under tensile loading. This behaviour is achieved by a specific material design which uses micro-mechanical effects to enhance the bridging properties of the fibres. In the presented research work, a series of large-scale uniaxial tension tests was performed to investigate the influence of the steel reinforcement on the load-bearing capacity as well as on the deformation and cracking behaviour of slabs made of SHCC. Both the global deformations of the test specimens and local deformations of the reinforcement bars were measured. The experiments showed that the load-bearing behaviour of the structural elements is characterized by multiple cracking of SHCC This results in a quasi-elastic, tension-stiffening behaviour of the tension element after the initial cracking strength was reached. For a realistic description of this load bearing behaviour, a model for concrete stress-strain relationship is proposed.