切口混凝土梁断裂能的尺寸效应试验研究

本文通过13组46个三点弯曲切口梁试件的单调和循环加载试验，研究了混凝土断裂能OF的尺寸效应。结果表明，单调及循环加载试验中测得的混凝土断裂能几乎相等。在试验梁跨度、高度及截面宽度不变时，随切口相对深度的增加，混凝土断裂能呈线性降低趋势。在试验梁跨高比l/d二5~8时，混凝土断裂能随跨高比的增加而趋于降低。 

Experimental Investigation on the Size Effect of Fracture Energy or Concrete by Means of Three-Point Bend Test of Notched Beams

Forty-six specimens with notches divided into 13 branches are tested by means of three-point bend test under monotonic and cyclic loadings. The size effect of fracture energy G is studied. It is shown that the fracture energy G_F is almost equal under the two loading conditions, when span, depth and width of specimens arc constant, G_F decreases linearly as the relative notch depth increases, when the ratio of span to depth (l/d) is within 5 to 8, G_F also decreases as the ratio increases.