摘要
为了分析特殊支承连续箱梁桥的扭转力学性能,提出一个特殊支承箱梁单元,该单元考虑轴向拉压、竖向弯曲及约束扭转变形。通过引入位移变换矩阵,将箱梁轴线处的位移向特殊支承点处变换,以便满足特殊支承截面的位移约束条件。选取箱梁约束扭转微分方程的齐次解作为单元扭转位移函数,在初参数解的基础上,推导箱梁单元的约束扭转刚度矩阵。利用所提出的箱梁单元对一特殊支承3跨连续箱梁模型进行计算,其应力计算值与ANSYS壳单元计算值和实测值均吻合较好,验证该单元的可靠性。分析特殊支承连续箱梁与相应常规箱梁在偏心荷载作用下的扭转力学性能。研究结果表明:与常规箱梁相比,特殊支承箱梁具有更大的扭矩、双力矩、扭转角及广义翘曲位移,特殊支承箱梁的内力和位移具有更加复杂的分布规律。
A special-support box girder element was presented to analyze the torsional mechanical behavior of the continuous box girder bridge with special supports. The deformations of axial extension, vertical bending and restraint torsion were considered in the element. The displacements at the beam axis were transformed to the special support point by introducing the element displacement transformation matrix to satisfy the displacement constraint condition at the special support section. The homogeneous solution to the restraint torsion differential equation was adopted as the torsional displacement function of the element and the element stiffness matrix for restraint torsion was derived by applying the initial parameter solution. A three-span continuous box girder model with special supports was analyzed by using the element presented and the calculated results of stresses are in good agreement with the shell element results of ANSYS and the testing results, which verifies the effectiveness of the box girder element. The torsional mechanical behaviors of the continuous box girder with special supports and the corresponding regular box girder under eccentric load were analyzed in detail. The results show that the torque moment, bi-moment, torsion angle and generalized warping displacement of the box girder with special supports are larger than those of the corresponding regular box girder. The distribution of the internal force and displacement of the box girder with special supports is more complicated than that of the regular box girder.
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2016年第4期1312-1318,共7页
Journal of Central South University:Science and Technology
基金
国家自然科学基金资助项目(51268029
51068018
51468032)~~
关键词
连续梁桥
箱形梁
约束扭转
特殊支承
有限梁段单元
continuous beam bridge
box girder
restraint torsion
special support
finite segment element
作者简介
通信作者：张元海，博士，教授，博士生导师，从事桥梁结构设计理论研究；E-mail：zyhl7012@163．com
