Numerical and experimental analysis of lateral stability in precast concrete beams

Abstract

The lateral stability of long slender precast concrete beams requires great attention, particularly during transitory phases such as tilting and transportation. Lateral stability relates primarily to decreased bending and torsional stiffness resulting from cracking in the beam. An experimental investigation was undertaken into the problem of lateral buckling of reinforced concrete beams and the results were compared with a numerical model considering the materials' nonlinear behaviour. The tests revealed that the effect of torsion was less significant than that of lateral bending. The use of total stations in the tests to measure displacements proved to be an alternative that provided good results, taking into account the coordinates' changes in space. The torsional stiffness showed a numerical decrease of 20% caused by cracking during bending. The nonlinear behaviour of the materials calculated by the numerical model was in good agreement with the experimental strain in the concrete and in the reinforcement obtained in the tests.