Application of Microtomography to Fracture Processes in Cement-Based Materials

这是缅因大学和西北大学的联合研究项目。本研究的目的是观察单轴压缩条件下小体积水泥砂浆试件内部微裂纹的三维扩展情况。微裂纹将使用同步加速器x射线微断层扫描结合三维图像分析技术进行测量。该研究工作首次实现了以微米级分辨率对水泥基材料内部开裂进行定量测量。更清楚地了解断裂机制对于开发既强又韧的材料至关重要。近年来，利用亚微米毫米范围内的微细颗粒填充概念，研制出抗压强度可达800mpa的混凝土。研究了颗粒尺寸分布（反应性和非反应性）对断裂韧性的影响。

9523019 Shah This is a joint research project between University of Maine and Northwestern University. The objective of the research is to observe the three dimensional growth of internal microcracks in small cement and mortar specimens loaded in uniaxial compression. The microcracking will be measured using synchrotron x-ray microtomography combined with a 3-D image analysis technique. The research work represents the first time that quantitative measurements of internal cracking of cement-based materials have been possible at micron resolution. A clearer understanding of fracture mechanisms are critical for the development of materials which are both stronger and tougher. Recently, using the concepts of microfine particle packing in the range of submicron millimeter, concrete with a compressive strength of up to 800 MPa has been developed. The influence of particle size distribution (reactive and non-reactive particles) on fracture toughness is to be investigated.