中文摘要：

外方内圆偏心约束法是研究水泥基材料抗裂性能的有效方法，文中采用数值分析和试验分析验证了外方内圆偏心约束方法的底板摩擦力对净浆和砂浆收缩开裂影响的问题。结果表明，模具底板摩擦力的存在能够缩短水泥净浆或砂浆收缩的开裂时间，并且水灰比越大，具有底板摩擦力的试件开裂越快。

英文摘要：

The outer square and inner circle eccentric constraint method is an effective way to study the anti-cracking performance of cement-based materials. For the question of friction in the testing proce- dures ,using ANSYS with theoretical numerical analysis, outer square and inner circle eccentric constraint method is used to verify friction＇ s effect on different water-cement ratio of cement paste and mortar. The results show that the presence of friction can reduce cement paste or mortar specimens with friction cracks quickly as the water-cement ratio increases. shrinkage cracking time, the