Reliability Assessment of Cracked Reinforced Concrete Slab and Verification using a Full-Scale in-Situ Load Test

Abstract

This paper presents a case study focused on the deterministic and probabilistic structural assessments of a cracked reinforced concrete (RC) slab and evaluation using in-situ load testing. The case study explores the practical application of in-situ load testing as a diagnostic tool for evaluating the condition of the slab and determining its ultimate load-carrying capacity in the presence of cracks, and service loads are used to verify its serviceability. Through comprehensive analysis and interpretation of test results, this study aims to provide valuable insights into the structural performance of cracked reinforced concrete slabs and inform effective repair and rehabilitation strategies. The building under examination is a G+4 reinforced concrete structure constructed using ready mix concrete transported to the construction site. Upon inspecting the slab, which had a total thickness of 170 mm, numerous deeply mapped cracks were evident, visible from the slab's surface and extending through its entire depth. Structural analysis indicated that the design included sufficient reinforcement and that the loads acting upon the slab were not expected to induce the cracking. Factors such as poor construction practices, potential issues with the cement used, and excessive evaporation may have contributed to the occurrence of these cracks, necessitating repairs. A full-scale in-situ load test was performed following ACI 318-08 testing procedures and results show that the slab under investigation is reasonably safe against serviceability and strength requirements with “no evidence” of failure.

Keywords

• Structural assessment
• RC slab
• cracks
• in-situ load test
• load-carrying capacity

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