桥面铺装对中小跨径桥自振频率的影响分析

为了对桥梁结构计算中是否需要考虑桥面铺装质量对桥梁结构自振频率的影响进行分析,以曲线连续梁桥为对象,采用空间梁单元建立动力分析模型,通过模型桥的实测与计算结果对比分析,验证了空间梁单元模型是可行可靠的。基于现场曲线桥,对实桥进行自振频率实测,与此同时,分别建立4种有限元模型来讨论桥面铺装、护栏质量和尺寸对自振频率值的影响,通过现场实测与4种模型计算的自振频率值得比对分析,表明：模拟考虑的越精确,计算结果与实测结果越接近,但计算工作量大；以精确模拟计算结果为参照,裸梁的计算更接近。针对新建桥,不考虑铺装质量的结果更加合理,在设计计算中往往考虑桥面铺装的质量,却不考虑其对截面几何特性的影响是偏不利的。

Effect of Deck Pavement on Natural Frequency of Medium-span and Short-span Bridges

In order to analyze whether it is necessary to consider the influence of the mass of deck pavement on the natural vibration frequency of bridge structure in the calculation of bridge structure, this paper choose the continuous curved beam bridge as an object to establish dynamic analysis model with beam-element and make a comparative analysis of actual measurement and calculated results of model bridges. It is proved that the beam-element model is feasible and reliable. Based on the real curved bridge, natural frequency of vibration is measured and the four kinds of finite element models are established to discuss the influence of bridge deck pavement and the mass and size of the guardrail on the natural vibration frequency. The comparison and analysis of the measured value and the calculated value of the natural frequency of vibration show that: the more accurate the simulation is considered, the closer the calculation results are to the measured results, but the greater the calculation workload is; The calculation of the bare beam is closer to that of the accurate simulation results. It is more reasonable not to consider the mass of deck pavement for the new bridge. However, it is unfavorable to only consider the mass of the bridge deck pavement in design and calculation process without taking the influence of the geometric characteristics of the section into account.