In order to research the toughening and crack control effect on structure of the domestic ECC and ordinary PVA fiber reinforced concrete

the material and construction member test were carried out.By the four points bending experiment

it is found that the peak load and the corresponding tensile strain of ECC are much great than that of ordinary concrete and PVA fiber reinforced concrete.And crack width can be better controlled.The crack width is smaller and spreads slower than ordinary reinforced concrete.Using the ECC

PVA fiber concrete as the bottom protecting layer of the reinforced concrete beam of different height

it is found that a 1/4h ECC has the best toughening effect.And when crack width reached 0.2 mm

the load-bearing capacity of 1/4h ECC increases 1.6 times than that of ordinary reinforced concrete

the peak load increases bout 12%.And then

the crack width is smaller than reinforced concrete in the same load when the ECC is used as beam bottom layer.And ECC can effectively control the rapid growth of crack width

indirectly improve the durability of structures.