不同型式的碾压混凝土拱坝诱导缝开裂试验研究

Experimental research on cracking for different types of induced joints of RCC arch dam

根据多组不同削弱度的深埋矩形裂缝和穿透裂缝的碾压混凝土试件单轴拉伸试验结果,建立了试件等效强度和面积削弱度的关系,试验结果表明,碾压混凝土材料的断裂韧度和抗拉强度的比值同常态混凝土基本相同,相同削弱度的矩形预留缝试件的等效强度比穿透裂缝试件的等效强度低4%-8%左右.因此,碾压混凝土拱坝诱导缝建议选用间断矩形型式.

Based on the experimpental results on two types of RCC speciment（i.e. the immerged rectangular crack and penetrated crack respectively）with different weakening ratio under axial tensile stress, the relation between equivalent strength and ratio of reduced area for specimens is obtained. The results show that the fracture toughness of RCC materials is approximately same as that of normal concrete materials, and the equivalent strength for specimens with immerged rectangular crack is less than that of specimens with penetrated crack, the value of ratio is 4% to 8%. Therefore, the discontinuous rectangular type of induced joints is suggested to applied in RCC arch dams.