本文报导了我国第一座双线铁路槽型梁在三向预应力作用下的应力变形状态试验结果,并且与薄壳有限元法的计算值进行了比较分析。试验证明,在纵向预应力作用下的计算截面应取道床板全部截面作为主梁下翼缘共同工作。在横向束作用下,在桥中线平均分布宽度相当于半个横向宽度的距离。竖向预应力筋能在腹板混凝土和箍筋中有效地建立起竖向预应力。试验也表明,在单束作用下,在近端部或板边会产生相当大的应力集中现象,并对张拉顺序提出建议。从薄壳有限元法计算与实测值比较得出,在结构整体变形上及道床板的应力变形上,两者符合得相当好。但对角隅部分的应力分析宜用更精确的方法进行。 This paper reports the test results of the stress and deformation states of the first double-track railway girder under the three-direction prestressed force and compares the calculated results with the finite element method of the thin shell. The test proves that the calculated cross-section under the action of longitudinal prestressing should be taken as the work of the lower flange of the main girder with the full cross-section of the roadbed. Under the action of transverse beam, the average distribution width in the bridge midline corresponds to the distance of half of the lateral width. Vertical tendons can effectively establish vertical prestress in web concrete and stirrups. Experiments also show that there is considerable stress concentration at the proximal or plate edges under single beam action and recommendations for the tensioning sequence. The comparison between the finite element method and the measured data shows that the two are in good agreement with the overall structural deformation and the stress-strain of the ballast. However, the stress analysis on the corner should be done in a more accurate way.