我国公路混凝土拱承载力计算通常将拱圈等效为梁柱后,按砌体柱公式计算承载力.通过混凝土柱和砌体柱轴压构件和偏压构件的破坏模式与计算方法进行对比分析,结果表明:混凝土柱的破坏模式、截面强度、偏心率折减系数、纵向弯曲系数与砌体柱均有所不同;混凝土柱截面强度采用砌体柱的强度计算将小于实际值;而混凝土柱纵向弯曲系数、偏心率折减系数均小于砌体柱.因此,混凝土偏压柱按砌体柱的计算方法计算将大于实际承载力,偏于不安全也不合理.混凝土柱的承载力应采用合理方法计算.
In the bearing capacity calculation methods of highway concrete arch in our country,when the arch is equivalent to beam-column,the formulas of masonry column are often used to estimate the load bearing capacity of the concrete arch. For the irrationality of this method,through the analysis and comparison of the the failure modes and calculation methods of axial compression member and eccentrically loaded member between concrete column and masonry column,the results show that the the failure modes,the intensity of cross section and the eccentricity reduction factors as well as the buckling coefficients of reinforced concrete columns are different from that of masonry columns; if the formulas of masonry column are used to estimate the intensity of cross section of concrete column,the result will be smaller than the actual value; however the buckling coefficients and the eccentricity reduction factors of concrete column are smaller than that of masonry column. therefore,if the formulas of masonry column are used to estimate the eccentrically loaded concrete columns,the results will be greater than the actual value,which is unsafe and unreasonable,the calculation of the bearing capacity of the concrete column should adopt reasonable calculation methods.