水中養生および恒温度養生中におけるセメントモルタルの亀裂発生挙動に関する研究 : AE法を用いたセメント系材料の亀裂挙動および破壊挙動の測定と解析 その1

抄録

We measured the weight loss, the coefficient of contraction and cracking behavior of cement mortor and cement paste by AE technique. The experimental results are summarized as follows. 1) The microscopic fracture is occured, when suddenly changed rate of shrinkage and expansion increase. 2) The shrinkage crack of cement mortar is occured from immediately after standard curing to about 5 hours. But from about 5 hours, it is no occured. 3) The shrinkage crack of cement paste is occured from immediately after standard curing to about 3 hours. After that, it's occured periodically. 4) The relation of AE event energy and amount of shrinkage crack is expressed as follows. Cement paste<Cement mortar using standard sand<Cement mortar using River sand.