中文摘要：

为了分析时速250km/h铁路32m跨度双线标准箱梁的畸变效应,基于板壳有限元建立了畸变效应分析的数值模型。采用板壳有限元方法和传统解析方法,对比计算仅单线活载作用下的畸变应力分布规律。通过定义翘曲比例系数,研究高跨比、宽跨比和壁厚等设计参数对畸变应力的影响规律。研究结果表明：与传统解析解比较,板壳有限元法更适合于箱梁畸变效应的分析。单线活载偏心作用下,跨中截面箱梁顶板靠近翼缘板边缘部位的翘曲比例系数可达11.6%;腹板与底板相交处翘曲比例系数最大,可达13.9%。跨中和l/4截面的翘曲比例系数ξ分析表明,现有箱梁设计参数合理,跨中最大翘曲比例系数小于15%,而l/4截面基本为0。箱梁高跨比、宽高比、壁厚等设计参数对畸变效应均有一定影响,总体规律是畸变效应随高跨比、宽高比和壁厚的增大而减小。

英文摘要：

In order to calculate the distortion effect of double track railway box girders at the speed of 250 km/h, a numerical model is established based on shell finite element method.Using finite element method and the tradi-tional analytical method,distortion stress is calculated and analyzed under only single track live load.By defi-ning the parameters of warping ratio,the rules of warping stress influenced by the design parameters of high span ratio,width span ratio and wall thickness are analyzed.Comparing with the traditional analytical solution,the fi-nite element method is more suitable for the analysis in the box girder distortion effect.Under eccentric live load of single track,the value of warping ratio on flange edge of top plate is 11.6%,while it is 13.9%near the in-tersection of the web and the bottom plate which is the maximum in mid-span section.Analyzing the warping ratio on sections of mid-span and 1/4,it is shown that the beam design parameters of existing box is reasona-ble.The maximum warping ratio on mid-span section is less than 15%,while nearly 0 on 1/4 section.The de-sign parameters of high span ratio,width span ratio and wall thickness can influence the sectional distortion of box girder.It is found that the distortion effect decreases with the increase of the high span ratio,width span rati-o and wall thickness.