A improved strength model was developed to predict the punching shear strength of interior slab-column connections without shear reinforcement. Considering the damage due to flexural cracking at slab-column connections damaged by flexural cracking, the punchingshear force was assumed to be resisted mainly by the compression zone of the critical section. The punching shear strength was defined by using the material failure criteria of concrete. In the evaluation of the punching shear strength, the interaction between the shear stress and the compressive normal stress developed by the flexural moment of the slab was considered. The proposed strength model was verified by existing test specimens.

• Choi, Kyoung-Kyu(Research Professor, Dept. of Architectural Engineering, Dankook Univ.) Corresponding author
• Cho, Seung-Ho(Research Professor, Dept. of Architectural Engineering, Dankook Univ.)
• Park, Hong-Gun(Professor, Dept. of Architectural Engineering, Seoul National Univ.)
• Lee, Sang-Hyun(Assistant Professor, Dept. of Architectural Engineering, Dankook Univ.)
• Chung, Lan(Professor, Dept. of Architectural Engineering, Dankook Univ.)