复杂格构式组合臂架结构起升平面外稳定性分析研究

发布时间：2018-05-20 01:02

本文选题：复杂臂架结构 + 格构式臂架　；参考：《哈尔滨工业大学》2013年硕士论文

【摘要】：为了满足风电、核电行业的整体吊装要求，具备大起升重量、大起升高度的组合臂架式起重机得到快速发展，但是臂架的高耸化、格构化却导致稳定性问题突显。本文以双吊点起重臂架和主副臂组合臂架为模型，采用微分方程法推导出其临界失稳方程，并对格构式臂架的整体稳定性和单肢稳定性的改进提出具体的措施。论文的主要研究内容和研究成果如下：给出了双吊点起重臂架的临界失稳方程，充分考虑到吊点与吊臂截面形心偏心所引起的附加弯矩对拉杆力的影响，并针对附加弯矩的起重臂提出了一种简化的力学模型，供设计人员计算拉杆力时使用。通过建立三根拉绳的力平衡方程获得拉绳交点处的坐标，将拉绳对吊臂的作用力表示成吊点处挠度的函数，借助变形协调条件联立方程组，由系数矩阵行列式为零得到具有腰绳的吊臂平面外临界失稳方程。提出了弯曲直梁在主副臂交点处的角度协调条件，将纤绳和撑杆等效成二力杆件，联立力系平衡方程和变形协调条件获得具有纤绳装置的组合臂架平面外失稳方程。提出了将臂架所承受的外载荷分解到各平面桁架的方法，给出了提高臂架整体稳定性和单肢稳定性的具体措施，，并以三角腹杆系臂架为例，分别推导出主臂和副臂在平面内和平面外两种情况下各主弦和斜腹杆内力的计算公式，为判断单肢失稳位置、提高模型抗失稳能力提供理论支持。
[Abstract]:In order to meet the requirements of wind power, the combined boom crane with large lifting weight and high lifting height has been developed rapidly. In this paper, the critical instability equation is derived by using the differential equation method based on the model of double lifting point lifting boom and main accessory arm combined boom, and some concrete measures are put forward to improve the global stability and single limb stability of the lattice boom. The main contents and results of this thesis are as follows: In this paper, the critical buckling equation of lifting boom with double lifting points is given, and the influence of additional moment caused by eccentricity of lifting point and cantilever section on the pull rod force is fully considered, and a simplified mechanical model is proposed for the lifting arm with additional moment. For use by designers in calculating pull force. By establishing the force balance equation of three pulling ropes, the coordinate of the point of intersection of the rope is obtained, and the force of pulling rope on the boom is expressed as a function of deflection at the point of suspension, and the simultaneous equations of deformation and coordination condition are established with the help of the system of equations. Based on the coefficient matrix determinant of zero, the out-of-plane critical instability equation of the boom with waist rope is obtained. The angle coordination condition of the curved straight beam at the intersection point of the main accessory arm is proposed. The fiber rope and the brace are equivalent to the two-force member, and the equilibrium equation of the joint force system and the deformation coordination condition are obtained to obtain the out-of-plane instability equation of the combined arm with the fiber rope device. In this paper, the method of decomposing the external load of the boom to each plane truss is put forward, and the concrete measures to improve the overall stability and the single limb stability of the boom are given, and the triangular web boom is taken as an example. The formulas for calculating the internal forces of the main chord and the oblique web of the main arm and the accessory arm in and out of the plane are derived, respectively, which provide theoretical support for judging the instability position of the single limb and improving the model's ability to resist instability.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TH218

【相似文献】