体外预应力混凝土简支梁自振频率研究

Study on Natural Frequency of Externally Prestressed Concrete Simple Supported Beam

体外预应力技术经过多年的发展已被广泛应用于结构工程领域,而通过检测结构的固有频率变化来评估预应力结构的使用状况已成为工程检测的研究重点。本文以经典的Timoshenko梁理论模型为基础建立预应力与梁自振频率间的理论关系模型,在前人研究的基础之上,通过实验数据的分析修正梁的自振频率计算公式,由修正后的公式知:预应力梁的自振频率与预应力呈正相关的变化关系,而此公式对于直线型体外筋梁的一阶频率理论值与试验值误差较小,在工程应用中具有一定实用性。

After years of development, the externally prestressed technology has been widely used in the field of structural engineering,and the changes of the natural frequency in the detection structure can be used to evaluate the condition of the prestressed structure, which has become the focus of the study of engineering detection. Based on the classical theory of Timoshenko beam model, establish the theoretical relationship model between the natural frequency of prestress and beam, and on the basis of previous studies, through the analysis of the experimental data, modify the natural frequency formula of beam. The modified formula shows that there is a positive relationship between the natural frequency of the prestressed beams and the prestress; this formula can reduce the error between the theoretical value and the test value of the first-order frequency of beams with external linear tendons, which has certain practical value in engineering application.