CAJ | 학술논문

根据变形协调条件及平截面假定,首先推导了连续箱梁日照温差总应力的一般公式,并针对试验观测资料及我国铁路桥梁和公路桥梁设计规范中的不同日照温差梯度模式,给出了温度应力的实用计算公式.为了能够进一步应用于斜交连续箱梁,以斜交连续梁的三力矩方程为基础,给出了温度次弯矩的计算方法及公式.编制了相应温度应力分析程序,结合工程实例分别对正交和斜交连续箱梁的温度应力进行了计算分析,并与ANSYS有限元计算结果进行对比.通过分析连续箱梁日照温差应力沿梁跨方向的分布规律,提出在设计预应力混凝土连续箱梁桥时,应特别注意对主跨跨中截面进行正应力验算及正截面抗裂性验算,并注意对中支点及其附近梁段靠近重心轴处的斜截面抗裂性进行验..
근거변형협조조건급평절면가정,수선추도료련속상량일조온차총응력적일반공식,병침대시험관측자료급아국철로교량화공로교량설계규범중적불동일조온차제도모식,급출료온도응력적실용계산공식.위료능구진일보응용우사교련속상량,이사교련속량적삼력구방정위기출,급출료온도차만구적계산방법급공식.편제료상응온도응력분석정서,결합공정실례분별대정교화사교련속상량적온도응력진행료계산분석,병여ANSYS유한원계산결과진행대비.통과분석련속상량일조온차응력연량과방향적분포규률,제출재설계예응력혼응토련속상량교시,응특별주의대주과과중절면진행정응력험산급정절면항렬성험산,병주의대중지점급기부근량단고근중심축처적사절면항렬성진행험..
According to the harmonious condition of deformation and the assumption of plane section, the general formula for calculating sunshine thermal stress of continuous box girders was derived. Then based on the existing experimental results and the modes of sunshine thermal gradients in the present code for design of railway and highway bridges, the practical calculating formula of thermal stress was presented. The method and formula for calculating secondary thermal bending moment were provided tnnzekew continuous box girders based on the three-moment equation of skew continuous beam. The corresponding programmaing was fulfilled. The thermal stresses in figh and skew continuous box girders were calculated through engineering practice and good agreement was achieved compared with those of ANSYS calculation. The longitudinal distribution pattern of the thermal stress in continuous box girder bridges was ascertained. It is put forward that (1) much attention should be paid to the checking calculation for nonnal stress and crack resistance at midspan cross-section of central span in the design of prestrssed concrete continuous box girder bridges; (2) the checking calculation for crack resistance of inclined cross -section near gravity axis in internal support area should also be treated seriously.