专业英语第十一章 房屋结构工程 ppt课件.ppt

影响无粘结的梁的极限弯矩能力，但不影响或者根本不影响相同方式下的有粘结的梁的变量包括如下： 钢筋束中的有效应力大小； 跨高比； 材料特性； 加荷方式（弯矩图的形状）； 施加预应力的钢筋束的断面； 在施加预应力的钢筋和导管之间的摩擦系数； 有粘结的非预应力钢筋的数量。 A method of computing the ultimate strength of prestressed members (with unbonded tendons) that takes into account the variables listed above has been proposed by Pannell. This method is based upon experimental data and is considered slightly conservative. Pannell已经建议用以计算考虑上述列出变量的（具有无粘结的钢筋束的）预应力构件极限强度的方法。该法是基于试验数据，并且考虑时稍有保守。 It should be recognized that the ultimate moment capacity of a member stressed with unbonded tendons, unlike members with bonded tendons, may be adversely affected by unintentional variations in the effective prestress. Hence, it is considered prudent（谨慎的）to exert（给予）more care in estimating the losses of prestress and in supervising（监控）the stressing（加压）of unbonded members than would be considered necessary for bonded members, in order to assure the desired results are obtained. 应该承认，不象具有有粘结的钢筋束的构件，受到无粘结的钢筋束施加应力的构件的极限弯矩能力，可能会反过来受到有效应力不经意的变化的影响。因此，为了确保获得期望的结果，比起需谨慎考虑有粘结的构件而言，在估计预应力损失和监控无粘结的构件加压时更加予以小心谨慎，这被认为是谨慎的（做法）。 Structural Analysis 结构分析 A structure consists of a series of connected parts used to support loads. Notable examples include buildings, bridges, towers, tanks, and dams. The process of creating any of these structures requires planning, analysis, design, and construction. Structural analysis consists of a variety of mathematical procedures for determining such quantities as the member forces and various structural displacements as a structure responds to its loads. Estimating realistic loads for the structure considering its use and location is often a part of structural analysis. 结构由一系列相连的用以支撑荷载的构件组成。显著的例子包括建筑、桥梁、塔、水箱和大坝等。建造这些结构中的任何一个的过程需要规划、分析、设计和建造。结构分析包括各种各样的数学程序以确定诸如当一个结构对荷载有响应时构件的力和不同结构位移的大小。根据结构的使用和位置来估计它的实际荷载经常是结构分析的一部分。 Only two assumptions are made regarding the materials used in the structures of this chapter. First, the material has a