【作者】 张运波；

【导师】 潘家英； 李永强；

【作者基本信息】 中国铁道科学研究院 ， 桥梁与隧道工程， 2011， 博士

【摘要】 随着我国高速公路和高速铁路的发展,高墩大跨桥梁结构将在深沟峡谷中大量采用。薄壁高墩的大量采用,使桥墩的刚度削弱,柔度增大,致使桥梁整体稳定性尤其施工过程中高墩的稳定性减弱,并且受外界环境影响敏感度增加,比如外界气温变化、太阳辐射、阵风等因素的影响。由于高墩大跨桥梁施工周期长,日照环境温度对薄壁空心高墩施工过程中应力、变形及稳定性的影响不容忽视。本文在研究薄壁空心高墩结构温度场及其温度应力特点的基础上,结合仙神河大桥等实际桥梁工程,对150.07m的八边形空心墩以及97.5m高的双肢薄壁空心墩温度场分布进行了测试与分析,找出了八边形空心墩以及双肢薄壁空心墩温度场的分布规律,并提出了适合八边形空心墩以及双肢薄壁空心墩温度场分布的计算公式,经与温度分布实测数据对比,该公式具有一定的精度和准确性。文中还研究了高墩大跨混凝土桥梁结构与外界环境进行热量传递的机理,在日照辐射以及热传导理论的基础上二次开发了ANSYS软件,利用其自带的程序语言APDL编写了计算日照温度场、温度应力与变形的命令流,通过其界面语言UIDL和TCL/TK将开发的命令流内嵌于ANSYS界面中,实现任意地点、任意时间、任意截面形式的混凝土空心墩在日照温差作用下的温度场分布、温度应力与变形的计算。该程序具备一定的前后处理功能,能够考虑地理经纬度、桥梁方位角和风速等因素,分析任意形状和尺寸的高墩任意时刻的二维日照温度场和温度应力的分布情况。用该程序计算了晋济高速上的仙神河大桥高墩温度场分布,其结果与监控实测值吻合较好。同时,计算结果也表明温度应力值是相当大的。在上述工作基础上,作者还研究分析了温度效应对高墩结构稳定性的影响,结果表明,温度效应对高墩结构稳定性的影响也不容忽视,必须引起重视。论文最后分析讨论了几何非线性对高墩稳定性的影响,建议了增强高墩稳定性的措施,探讨了温度效应对高墩桥梁结构施工监控的影响,可以为高墩大跨桥梁的施工监控提供参考。更多还原

【Abstract】 With the development of China’s expressway and high-speed railway, a great deal of high pier long span birdge will be used in canyon areas.. It means, the pier’s stiffness will be weaken. So bridge’whole stability will be weaken too, especily during the constructing stage. And the degree of sensitivity about external environment will be increased. Such as variation of environment temperature, solar radiation, gust and so on. Because of long constructing time, the environment temperature’s influence on high pier’s stability during constructing stage must be pay attention to.In this thesis, on the basis of studing on temperature distribution mode and temperature stresses for high pier with thin-walled hollow sections, parallel with construction of XianShenHe bridge, the temperature gradientcurves about 150.07m high hollow octagon pier and 97.5m high double-column pier are measured and analyzed. The estimate formula for those high pier be brought up. With this formula, the calculation result agrees well with the measured data. Based on heat transfer theory,the mechanism of heat transfer between high pier and external environment be researched. The ANSYS software is re-developed on the basis of solar radiation and heat transfer theory. By using language APDL, The command lines of calculations about temperature gradientcurves, temperature stress and temperature deflection for high pier with thin-walled hollow sections be written. . The commond be inbuilted in ANSYS interface by means of interface language UIDL and TCL/TK. The result of temperature gradientcurves ,temperature stress and temperature deflection about high hollow pier be computed. The program had the functions for pretreatment and aftertreatment. can be used for high pier of any shape and any size with different geography longitude and latitude, different bridge’s azimuth angle and wind velocity. The program is used to analyze temperature gradientcurves about XianShenHe bridge’s high pier of JinJi High Way. And the computed outcome agrees well with the measured data. Meanwhile,the results also show that the temperature stress is quite large.Based on the work mentioned above ,the temperature influence on stability of high pier bridges has been studed ,According to its result, more attentions should be paid to temperature effect on stability of high pier bridges. At last, the geometric nonlinear’s influence on high pier’s stability is discussed,and the measures to increase stability of high pier bridge is suggested. The temperature influence on monitoring and controling for high pier bridge construction is also discussed, which is referencable for those kinds of works marized.更多还原