Research progress of punching shear performance of reinforced concrete slab-column joints
In order to improve the anti-punching shear performance of slab-column joints and thus promote its engineering application,the effects of different arrangement forms,shapes and sizes,geometric parameters and combinations forms of various types of anti-punching shear elements on the anti-punching shear bearing capacity of the joints were compared.The research status of repair and reinforcement of damaged slab-column joints was summarized.The research results on the anti-punching shear performance of slab-column specimens with openings under different openings sizes,distances,numbers,shapes and eccentric loads were sorted out.The calculation method of the anti-punching shear bearing capacity of slab-column joints with and without the punching shear reinforcement and configuration of steel shear frame,and the prediction method of the anti-punching shear bearing capacity of slab-column joints based on machine learning were summarized.The results show that the various types anti-punching shear elements can improve the punching shear performance of slab-column joints by changing the arrangement forms,shape and size,geometric parameters and the combination of elements.The larger the size,farther the distance and more the number of openings in the slab,the more unfavorable the anti-punching shear performance of the joints.The anti-punching shear bearing capacity calculation formula based on numerical simulation and specification improvement only have high prediction accuracy for specific tests,has not yet formed uniform bearing capacity calculation formula,and the prediction model of punching shear bearing capacity based on machine learning is the focus of future research.In addition,further research on the repair and reinforcement methods of damaged slab-column joints is also of great significance for improving the theoretical system of anti-punching performance of slab-column joints.