A new approach to testing reinforced concrete flat slabs

摘要

This paper outlines a new experimental method developed to test flat slabs with simple uniform loading and improved boundary conditions. A new form of punching shear reinforcement, which will increase the punching shear resistance without affecting the flexural resistance, is used. Available experimental methods to test flat slabs are reviewed to demonstrate the simplicity of the new approach. To show the effectiveness of both the method and the shear reinforcement, some experimental results are included. In the design of slabs, in addition to self-weight a uniform imposed load is usually considered. But in the laboratory, applying this uniform load is challenging. This is further complicated by the requirements to maintain proper boundary conditions. One way adopted in the past was testing multipanel slabs with multiple point loads. However this is an expensive approach. Therefore in this paper a very simple approach to test isolated flat slab panels with improved boundary conditions is presented. A special vacuum rig was constructed at Cambridge University Engineering Department. Details of the vacuum rig and some experience from experiments are given: the method seems promising. It is concluded that with further tests the shear reinforcement introduced in this paper could be useful in practice.