Research And Numerical Simulation On The Mechanical Properties Of Strain Hardening Cementitious Composites (SHCC)

As the country's economic growth, the large-scale construction of infrastructure are being builded.As the most widely used building materials,the concrete can be good model .easy-to-derived and have a high compressive strength which can not be replaced,but the performance of traditional cement-based materials have poor toughness, low tensile strength,easy to crack and other defects.These characteristics greatly limit the durability of concrete and affect its applications in some special structures.With the development of various fiber reinforced concrete,a micromechanics optimized Engineered Cementitious Composite(ECC) Can significantly improve the toughness of concrete,present the characteristics of strain hardening and improve the durability of concrete.However, ECC material has more strict requirements on the sand particle size and higher cost of production.It is not suitable for inputing to large-scale project practice .It can only be used in a conversion of some key parts of the reinforcement.To reduce production cost of ECC,we get another Strain-Hardening Cementitious Composites(SHCC) by improving the cooperation ECC.SHCC has a low cost.Its maximum uniaxial tensile strain meets the computing requirements.It shows the cement-based material properties of strain hardening and characteristics of multiple micro-cracks cracks.While the toughness performance is not good as ECC,it is enough to meet the durability requirements of cement-based material and engineering demands.In this projects, various testing method including wedge splitting,3 point bending,4 points bending and direct tensile test have been applied to specimens with different mix proportion.Through the study of the testing process, specimen failure mode and fracture energy,we get the the mechanism of strain hardening and use the strain hardening parameters to describe the strain hardening properties of materials.By dealing with the experimental results of three-point bending and four-point bending using the consoft programe,we get the strain hardening parameters of SHCC.