钢纤混凝土裂纹尖端应变场的实验研究

Application of Laser Speckle Interferometry to Determine Strain Field Around Crack-tip in Steel Fiber Reinforced Concrete

本文应用散斑干涉技术对四组含纤量分别为０，０．５％，１％，１．５％的钢纤混凝土三点弯曲裂纹试件的裂纹尖端位移场进行了测试，并换算为应变场。对钢纤混凝土裂纹开裂的基理进行了探讨；验证了最大拉应变准则；并测定了断裂韧度Ｊ１ｃ。

Laser speckle interferometry was applied to obtain full field crack-tip displacements of steel fiber reinforced concrete specimens subjected to 3-point bending. These specimens were classified into four groups in which the contentS of fiber were 0%, 0. 5 %,1 % and 1. 5% respectively. The displacement fields were transformed into strain fields. The main factors caused the crack growth were studied. The criterion of maximum strain was verified.Aside from these, the fracture toughness J1c was also determined.