自然环境下混凝土箱梁横截面温度场理论及试验研究

Analysis and Experimental Research of Temperature inside Cross Section of Concrete Box Beam in Complex Natural Backgrounds

以单箱单室混凝连续箱梁桥为分析对象,利用热传导理论与有限元软件ANSYS相结合的方法计算其截面温度理论分布,并将理论值与实测值、规范值进行比较。文章以国家重点工程沙溪河特大桥为例,进行温度场的有限元计算,通过对理论值与实测值比较,分析了利用有限元软件计算温度场产生误差的原因,并提出相关建议。在得出桥梁温度场的情况后,沿梁高一定长度取温度最大值,将得出的温度梯度模式与现行规范进行比较,发现其形式近似于新西兰规范。由于沿界面梁高会产生较大的温差,因此在实际计算和施工中,温度分布及相应产生的温度应力需要引起高度重视。

Taking a single carriageway and single cell box continuous concrete girder bridge as the analysis object, this paper calculates the theory distribution of section temperature by combining heat transfer theory with finite element software ANSYS, and compares theoretical value with measured value and standard value. It also takes the Shaxi river super major bridge, a national key project, for example, calculating the temperature filed, through comparison of theoretical value with the measured value, analyses the causes of errors in the calculation of temperature field using finite element software, and puts forward relevant suggestions. After drawing temperature field, take the highest temperature value a- long the beam length, through comparing temperature gradient model with the current specification, the form similar to New Zealand norms is found. As temperature difference occurs along the interface beams, so in practical computation and construction, attention must be paid to the temperature distribution and the temperature stresses derived from it.