Experimental research and numerical simulation of influence of pre-stress values on the natural vibration frequency of concrete simply supported beams

Abstract

To study the relationship between the fundamental frequencies and pre-stress values, based on experiments and numerical simulation, the simply supported was excited under different pre-stress values through using the hammering method. The collected acceleration signals in the mid-span of the beam were processed and analyzed to obtain the relationship between the fundamental frequency and pre-stress values. As shown from the analyzed result, the relationship between the fundamental frequency and pre-stress values could not be explained better based on the traditional “Euler-Bernoulli Beam Equation” theory. The fundamental frequency of the pre-stressed beam with the hammering method would be increased with the increasing pre-stress value. When the hammering method was introduced into the numerical simulation, its analysis result and the experimental result were very approximate and presented a small error, which indicated the feasibility and accuracy of the analyzed method. When the pre-stress value was a constant, the fundamental frequency of the beam would be increased with the increasing eccentric distance of the pre-stressing tendon. When other conditions were constant, the fundamental frequency of the beam presented a decreasing trend with the counterweight at the upper part of the beam.