Orthogonal Test Research on Compressive Strength Size Effect of ECC

Engineered fiber reinforced cementitious composite (ECC) can significantly improve the seismic performance and durability of concrete structures, which has pseudo strain hardening and multiple cracking performances. Through 32 groups of 192 specimens for compressive strength of ECC, the orthogonal test study on the cube compression failure process, and further research on water binder ratio, fiber content by volume, fly ash content and sand binder ratio of 4 kinds of factors on the size effect of ECC cube compressive strength. The test result shows that: PVA fiber content increases, ECC compressive toughness is improved obviously; water binder ratio and fiber content are the main factors which affect the ECC compressive strength and size effect. When water binder ratio decrease, the compressive strength of ECC materials improve and size effect coefficient increase. Fiber content increase, the compressive strength of test block increase and the size effect coefficient increase. Through the bending tests, we know that: the fiber content by volume increases, the ECC flexural strength of the composite increases gradually.