Numerical Investigation on the Impact Resistance of Reinforced Concrete Pier

Abstract

This paper presents a numerical investigation on the impact resistance of reinforced concrete pier. The impact resistance of reinforced concrete pier was determined by simulating the impact from floating log onto a pier during flood, with and without scour. A single pier of 0.9 m diameter and height of 4.0 m was modelled based on the actual working drawing by Public Works Department of Malaysia. Concrete grade for pier varies from grade 30 to grade 150.The log impacting on pier resembles the impact load of 2.0 tonne as recommended in the design guideline. The numerical analysis is conducted with the aid of ANSYS Explicit Dynamics R14 software. Damage index was used to describe the fracture state of the pier. The flood velocity and impactor properties incorporated in the model were based on flood velocity studies and available hardwood in Malaysia. The results indicated that all the impacted pier exhibits local damage in the form of penetration and scabbing. The critical velocity for pier without scour ranges from 1.75m/s to 2.25m/s compared to from 1.75m/s to 3m/s with scour. The impact resistance of reinforced concrete pier is found to be insignificantly affected by pier concrete grade.