Experimental and numerical study on mechanical properties of cement paste pipes subjected to uniaxial tensile loading

The aim of this paper is to investigate the mechanical properties of cement paste specimens by both experimental and numerical methods. Firstly, the specimens subjected to uniaxial tensile loading were studied experimentally. Afterwards, numerical investigation was carried out based on the experimental observations. Two types of specimens were used, which were unnotched and single notched specimens. The uniaxial tensile experiments of the unnotched specimens provided the Young's modulus and tensile strength of the specimens. The complete stress-strain responses of the specimens were derived from the uniaxial tensile experiments on the single notched specimens. The crack initiation and propagation were discussed. The uniaxial tensile loading experiments were simulated by a 3D lattice model. The local mechanical properties of lattice elements were determined through simulations. The tensile simulations of the unnotched specimen provided the Young's modulus and tensile strength for the local lattice elements. Then, the softening behavior of lattice elements was obtained from tensile simulations of the single notched specimen. The experimental and simulated stress-strain responses and cracking process were compared with each other. It was found that the simulated results matched quite well with the experiments with the set of local mechanical properties that was determined. This set was used in a further study for the simulations on external sulfate attack.