Tensile membrane action in reinforced concrete slab

• Main Author: Wahyudi, Trieska Yokhebed
• Other Authors: Tan Kang Hai
• Format: Final Year Project
• Language: English
• Published: 2010
• Subjects: DRNTU::Engineering::Civil engineering::Structures and design
• Online Access: http://hdl.handle.net/10356/39672
• Institution: Nanyang Technological University

Unforeseen events, such as fire, impact, or blast have a potency to damage a key structural element of a building which, in turn, may lead to a partial or total collapse of the structures. The disproportionate total damage with respect to the original cause is commonly termed progressive collapse. One of the key structural elements which have high potential for progressive collapse when damaged is a penultimate column. In this report, Tensile Membrane Action (TMA) in Reinforced Concrete (RC) slabs as one strategy to mitigate the progressive collapse of a building structure is presented. The primary objectives of this report are to verify the occurrence and to understand the behaviour of TMA in laterally-unrestrained RC beam slab structure. In addition, a simple method to predict the enhancement of load-carrying capacity by the TMA is also introduced. An experimental programme to study the behaviour of TMA under internal penultimate column loss scenario is discussed. It has been confirmed by two test results that the load capacity of slab can be enhanced beyond the yield line capacity due to TMA. Towards larger central displacement, the enhancement should actually be more prominent. However, concrete crushing at the beam-column joints limits this enhancement. A simple model to estimate the enhancement of load capacity due to TMA in laterally- unrestrained RC slabs is also presented. It is predicted by the model that the slabs will fail due to fracture of slab reinforcement along the intersection of yield lines, which is similar to the failure mechanism observed in the tests. However, the effect of concrete crushing is incorporated into the model empirically, which makes the simple model a semi-analytical approach. Comparison with the test results shows that the semi-analytical model gives a good estimate of the overall load-carrying capacity of the slabs.