关键词: CA砂浆, 干湿循环, 应力-应变, 力学性能指标, 函数关系

Abstract: Uniaxial compression test on CA(cement-asphalt) mortar specimens in different drying and wetting cycle levels is carried out by using CSS8810-100KN electronic universal testing machine. The variation of mechanical property indicators against drying and wetting cycle level is obtained. Results show that CA mortar has strong toughness, and it’s stress-strain curve is divided into four phases initial compaction, elastic deformation, plastic deformation and strain softening. Peak stress, elastic modulus and damage power first increase and then decrease with the increase of drying and wetting cycle level. Secant modulus first increases and then decreases with the increase of axial strain, because the early drying and wetting cycles further hydrate the unhydrated cement in CA mortar and densify the structure of CA mortar, and the late drying and wetting cycles give rise to the emergence and expansion of micro-defects in CA mortar. Plastic work gradually decreases with the increase of cycle level, and the cycles damage the vibration damping performance of CA mortar. Through data transformation, the functional relationship between the mechanical properties of CA mortar and the independent variables is obtained, which facilitates the application of research results to practical engineering.

Key words: CA mortar, drying and wetting cycle, stress-strain, mechanical property indicators, functional relationship