陶粒砼Ⅰ-Ⅱ复合型断裂判据研究  

STUDY ONI-Ⅱ MIXED MODE FRACTURE CRITERION OF CERAMSITE CONCRETE

作　　者：陈云霞[1] 王启文[1] 曹祖同[1] 

机构地区：[1]天津大学土木工程系

出　　处：《天津大学学报》1993年第1期16-22,共7页Journal of Tianjin University(Science and Technology)

基　　金：国家自然科学基金

摘　　要：用混合有限元法,采用四边形等参单元算得三点弯曲梁和四点剪切梁的应力强度因子K_Ⅰ和K_Ⅱ。用对称三点弯曲梁和四点剪切梁试件测得陶粒砼K_(IC)和Ⅰ-Ⅱ复合型裂纹的临界K_Ⅰ、K_Ⅱ值。根据实验结果,建议了陶粒砼Ⅰ-Ⅱ复合型断裂准则和根据K_Ⅰ/K_Ⅱ值计算起裂角θ的公式。最后,与普通砼的结果以及断裂力学中3个复合型断裂准则进行了对比。In this paper, by using the mixed-mode finite element method and quadrilateral isoparametric element, the stress intensity factors K_Ⅰ of the symmetric three-point notched beam and K_Ⅰ, K_Ⅱ of the four point notched beams with various crack positions are computed. Through the fracture experiments with three-point notched beams and four-point notched beams, the fracture toughness K_(IC) of the mode Ⅰ fracture and K_Ⅰ, K_Ⅱ of the Ⅰ-Ⅱ mixed mode fracture are acquired. On the basis of the computational and exeperimental results, the fracture criterion for ceramsite concrete of the Ⅰ-Ⅱ mixed mode fracture and the formulation to estimate the initial fracture angle 0 in the Ⅰ-Ⅱ mixed mode fracture using K_Ⅰ /K_Ⅱ are proposed. Finally, the results presented in this paper are compared with those of both ordinary concrete and three mixed-mode fracture theories of fracture mechanics.

关 键 词：应力强度因子 断裂准则 陶粒混凝土 

分 类 号：TU528[建筑科学—建筑技术科学]