基于微观力学和断裂力学试验方法的MMFM-ECC配合比设计

MMFM-ECC design method based on micro mechanics and fracture mechanics

高性能工程水泥基复合材料(Engineered Cementitious Composites,简写为ECC)相对于普通混凝土材料具有较高的极限拉伸应变能力.相对于目前广泛采用的粗放式配合比列表法、绝对体积法、正交试验法的ECC配合比设计方法,采用基于微观力学和断裂力学模型(Micro-Mechanics and Fracture Mechanics,简写为MMFM)的ECC配合比设计方法在水泥基质和纤维参数的选择上具有更好的理论依据和科学性.研究采用我国云南昆明地方材料资源和工业废料通过MMFM-ECC配合比设计方法进行配合比设计,并通过轴向压缩试验、双面剪切和四点弯曲试验结果检测实际ECC的各项性能指标.通过比较ECC设计目标性能指标和试验测得的实际性能指标分析讨论了MMFM-ECC配合比设计方法对试验仪器、试验过程、试验样本数的具体要求.

High-performance engineered cementitious composites（ ECC） have a high ultimate tensile strain compare with the common concrete.Compared with the widely used formula method,absolute volume method and orthogonal test method,the design method based on micro-mechanics and Fracture Mechanics（ MMFM） prove to give scientific directions on choosing fibers and cementitious matrix. Local materials in Kunming have been used with MMFM-ECC method in this paper.The ECC specimens have been tested with axial compression,double-sided shear and four-point bending tests.The test results have been compared with the target performance index of the ECC at the very beginning of the MMFM-ECC design,and the requirements of the MMFM-ECC design including equipment,test process and sample numbers have been discussed.