预应力简支工字钢梁体外预应力筋自振频率计算方法研究  

Computation Method of Natural Frequencies of External Tendons of Prestressed Simply Supported I-Beams

作　　者：薛刚 张宪法 李景祥 顾永强 XUE Gang;ZHANG Xianfa;LI Jingxiang;GU Yongqiang(College of Civil Engineering,Inner Mongolia University of Science and Technology,Baotou 014010,Inner Mongolia,China)

机构地区：[1]内蒙古科技大学土木工程学院,内蒙古包头014010

出　　处：《噪声与振动控制》2020年第6期210-214,267,共6页Noise and Vibration Control

基　　金：内蒙古自治区自然科学联合基金资助项目(2018LH05008)。

摘　　要：为研究预应力简支钢梁体外预应力筋自振频率的计算方法,采用分级施加预应力方法,对2组简支工字钢梁施加不同型式的体外预应力,测试每级预应力下梁的振动信号。试验结果表明:随着张拉力的提高,体外预应力筋的固有频率增大,且偏心距对频率变化的影响较显著,线形布置方式的影响相对较小。对Ayaho Miyamoto提出的公式进行修正与改进,推导出不同线形布置工况下索力计算公式,并计算试验梁索力值,结果表明,索力公式计算值与实测值最大偏差为8.94%,能满足工程应用要求。Calculation method of the natural frequencies of the prestressed tendon of the prestressed simply supported steel beams is studied.The prestress is applied to the structure step by step.Different types of external prestress are applied to the two groups of simply supported I-beams.The vibration signals of the beams are measured for each prestress step.The test results show that as the tensile force increases,the natural frequency of the external prestressed tendons increases;the eccentricity has a significant influence on the frequency change;and the tendon arrangement has a relatively small influence on the frequency change.Afterwards,the formula proposed by Ayaho Miyamoto is modified and improved.The formula for cable force calculation under different tendon arrangements is formulated and the cable force value of the test beam is calculated.The results show that the difference between the calculated cable force value and the measured cable force value is 8.94%,which can meet the engineering requirements.

关 键 词：振动与波 体外预应力 简支工字钢梁 试验研究 固有频率 

分 类 号：O422.6[理学—声学]