The strain energy release rates g near crack tip under different conditions were calculated by employing three methods of the fracture mechanics ( j - integral , straightforward method and crack tip opening displacement method ) 并在有限元模拟中采用三种不同的断裂力学方法(裂缝顶端开口位移方法、直接方法、 j积分方法)计算了焊点断裂与否时的能量释放率g 。
( 1 ) in the case of short data set , to select embedding space parameters as fast and exact as possible , the improved across displacement method for selecting time delay and the relative gain ratio of false neighbors ( 1 )在短数据集情况下,为了快速、合理地选择嵌入空间参数,提出了延迟时间选择的交叉位移改进法和嵌入维数选择的伪近邻距离统计增长法,其特点是速度快、重复性好。
In accordance with the practical engineering , the foundation and the holes are meshed with different element . for this problem , compatible displacement method of different mesh is presented in this paper . on the other hand , the mechanism of the creeping is analyzed 针对实际工程中,地基与衬砌混凝土之间网格的不协调,本文给出了非一致网格协调位移解法,并探讨了混凝土的徐变机理。
In this paper , based on analyzing the matrix displacement method and the transfer matrix method , the author combined them to form a new method , which called matrix mixed method , and then used this method to calculate the internal force and displacement of skew bridges 本文在分析了矩阵位移法和传递矩阵法的理论基础上,将二者组合而成矩阵混合法,并应用于斜交格栅结构的内力与变形分析计算中。
Initial ground stresses of rock slope were simulated , using boundary displacement method ( bdm ) and stress function method ( sfm ) respectively , and combining with finite element method ( fem ) . the practical results indicate both methods can simulate the initial stress field with good effect 采用边界位移法和应力函数法,并结合有限元程序对岩质高边坡进行了初始地应力场的模拟与分析,实践结果表明这两种方法均能取得较好的效果。
When analyzing skew support continuous curved box girder bridge , curved grid girder analyzing method considering warping effect is applied . matrix displacement method is applied in analyzing skew support continuous curved thin - walled box girder bridge with restrained bearing . in order to convert original rigidity equations to structural rigidi ty equations that can be solved , bearing nodal displacement matrix can be introduced , then unknown quantities at the edge of beams can be consistent with the restrained directions of skew bearings , unit rigidity matrix and unit nodal forces can be gained . structural rigidity matrix can be composed according to matrix displacement method , so nodal displacements and inner forces on the end of the rod that are unknown can be gained calculating equations of inner forces on any cross - section can be solved 分析斜支承连续曲线箱梁桥时,采用考虑翘曲作用的曲线格子梁分析方法,应用矩阵位移法对具有约束支承形式的斜支承连续曲线薄壁箱梁桥进行分析,考虑到支座的约束条件并不与梁端弯曲角位移和扭转角位移的方向一致,引入支座节点坐标矩阵,使得梁端的位移未知量与斜支座约束方向一致,来计算单元刚度矩阵和单元节点力,然后按照矩阵位移法组集总刚并建立结构刚度方程,根据结构刚度方程即可求解未知的节点位移及杆端力,推导出任意截面处的内力计算公式。
This paper introduces the developing tendency of the space structure and the application of the pretensioned space lattice structure , summarize the analysis method and relation between lattice structure and pretensioned space lattice structure . dissertate the space pole - truss displacement method , tendon working principle , set forth the method of optimal design and whole process design . includes the use stage design and construction stage design of pretensioned space lattice structure 本文首先介绍了空间结构的发展趋势及拉索预应力空间网格结构的应用情况,概述了网格结构与拉索预应力空间网格结构的分析方法及其相互关系,论述了空间杆系桁架位移法,拉索作用机理,阐述了拉索预应力空间网格结构的优化设计及全过程设计的设计方法,包括拉索预应力空间网格结构使用阶段的设计和施工阶段的设计。
Concrete elastic modulus and concrete creep and shrinkage variety at different time are reckoned in by using time increment analysis method and concrete creep and shrinkage secondary force is calculated by using effective elastic modulus . bridge stability analysis program is developed on the base of structure matrix displacement method , the program adopts visual basic language , has friendly interface and visual data input windows . the buckling safety factor of currently finished structure is given as result 为计入混凝土弹性模量的变化及混凝土徐变收缩随混凝土的龄期与外荷载加载时间不同而变化的影响,采用时间增量法对每个计算阶段根据其阶段内时步数进行循环,以计算时段内弹性应力、应变增量和徐变、收缩产生的应力应变增量,利用有效弹性模量法计算混凝土徐变收缩次内力,在此基础上,结合结构矩阵位移法的基本理论编制开发了计入混凝土时效效应的高墩大跨径桥梁稳定分析程序。
In this paper , i have analyzed the distortion of continuous rigid frame bridge at the condition of temperature uniform change by displacement method and finite element method computer aided design program - sap91 . it included : the distortion and inner force condition at the bottom of single pier when it is consolidated , the distortion and inner force condition of thin double piers - rigid frame bridge ; the distortion and inner force condition of thin double piers - rigid frame bridge when the consolidation is elastic consolidation and confinement adopted different rigidity factor ; and the inner force condition of thin double piers - rigid frame bridge when the distance of piers is different 本文利用位移法和结构有限元电算程序sap91 ,对连续刚构体系桥梁在受到均匀温变情况下:墩底固接单柱墩、双薄壁墩连续刚构桥;墩底弹性固接时的双薄壁墩连续刚构桥采用不同转动约束刚度系数情况;以及双薄壁墩墩间距不同的连续刚构桥梁的受力情况进行了分析和比较。
Based on the nodal mechanics theory and generalized displacement method , equations that the thin - wall cylinder pile is simulated with the beam element are derived . the influence of the number of beam element is researched , and conclusion that the number of beam element and the number of soil layer should be uniform is draw up 应用节点力学的基本理论和广义位移法的基本概念,推导了用梁单元模拟薄壁筒桩的计算公式,研究了梁单元离散桩体结构时梁单元的数目对计算结果的影响,得出了梁单元数量宜与桩穿过土层数目相一致的结论。