. Chapter 1 . Structural Mechanics 结构力学1.1 Classification and Behavior of Structural Systems and Elements系统结构和元素的分类和作用1.2 Determinate and Indeterminate Structures 静定和超静定结构 1.3 Structural Dynamics 结构动力学Chapter 2. Structural Material 土木工程材料2.1 Materials for Concrete and Mix Proportion 砼材料及配比2.2 Properties of Concrete 砼的性能2.3 Steel Materials 钢材料2.4 Structural Steel Shapes 型钢Chapter 3. Structural Design concepts 结构设计3.1 Load conditions and Load Paths 负载条件和加载路径3.2 Limit State Design 极限状态设计Chapter 4. Concrete Structure 钢筋混凝土结构4.1 Flexural Behavior of Reinforced Concrete Beam 钢筋混凝土梁的弯曲性能4.2 Shear and Diagonal Tension in Reinforced Concrete Beam 钢筋混凝土梁的剪切和斜拉4.3 Bond , Anchorage, and Development Length 连接，锚固，基本锚固长度Chapter 1 . Structural Mechanics 结构力学1.1 . Classification and Behavior of Structural Systems and Elements系统结构和元素的分类和作用Common rigid elements include beams, columns or struts, arches, flat plates, singly curved plates, and shells having a variety of different curvatures. Flexible elements include cables (straight and draped) and membranes(planar, singly curved, and doubly curved). In addition, there are a number of other types of structures that are derived from these elements(e.g, frames, trsses, geodesic domes, nets, etc. )(figure 1.1)常见的刚性元件包括梁，柱，支撑，圆拱，平板，单向板弯曲面，具有不同的曲率的翘体。
柔性元素包括电缆（直披）和膜结构（平面，单向板弯曲面，双曲面）此外也有一些来自这些元素（如框架，桁架，测量短程线，网格等）Frames 框架The frame has rigid joints that are made between vertical and horizontal members. This joint rigidity imparts (给予) a measure of stability against lateral forces. In a framed system both beams and columns are bent or bowed（弯如弓的）as a consequence of the action of the load on the structure. 框架的垂直和水平直接有刚性连接，这样的节点给予了一定程度上的稳定性抵抗侧向作用力在一个框架的系统，梁和柱的弯曲或弓形弯如弓的形状都是结构上负载的作用效果Trusses 桁架Trusses are structural members made by assembling short, straight members into triangulated patterns. The resultant （组合的, 合成的）structure is rigid as a result of the exact （精确的) way the individual line elements are positioned relative to one another. Some patterns (e.g. a pattern of squares rather than triangles) do not necessarily yield a structure that is rigid (unless joints are treated in the same way as in framed structures). A truss composed of discrete elements is bent in an overall way under the action of an applied transverse loading in much the same way that a beam is bent. Individual truss members, however, are not subject to bending but are only either compressed or pulled upon. 桁架结构构件是通过短直杆组装成三角形的图案。
组合的结果的精确方式相对于彼此的位置的各行元素的结构是刚性的不一定会产生某些刚性的模型（例如，一个模型的平方不一定是三角形图案）（除非在框架结构中相同的处理）由分立元件组成的桁架在大致相同的方式，弯曲梁所施加的横向载荷的作用下，在一个整体方式的弯曲个人桁架构件，不能弯曲只能压缩或拉后Arches拱门 An arch is a curved, line-forming structural member that spans between two points. The exact shape of the curve and the nature of the loading are critical determinants as to whether the resultant assembly is stable. When shapes are formed by simply stacking rigid block elements, the resultant structure is functional and stable only when the action of the load is to induce in-plane forces that cause the structure to compress uniformly. Structures of this type cannot carry loads that induce elongations or any pronounced type of bowing in the member (the blocks simply pull apart and failure occurs). The strength of a block structure is due exclusively to the positioning of individual elements, since blocks are typically either simply rested one on another or mortared together. The positioning is, in turn, dependent on the exact type of loading involved. The resultant structure is thus rigid only under very particular circumstances.圆拱 一个拱形的弯曲线形成的结构部件，两点之间的跨越。
曲线的精确性质和性质是所得到的组件是否是稳定的关键决定因素当通过简单地堆叠刚性块体元件的形状形成的结构是功能性的和稳定的，又有当负载的作用是诱导面的力量时才导致结构的均匀压缩这种类型的结构不能进行负载诱导伸长或任何明显的拉伸（只需拉开块发生故障）嵌段结构的强度是由于单个元素导致的，由于块通常是在躺在另一个上或砂浆砌在一起只有在非常特殊的情况下，所得到的的结构才是刚性的The rigid arch is frequently used in modern building. It is curved similarly to block arches but is made of one continuous piece of deformed rigid material. If rigid arches are properly shaped, they can carry a load to supports while being subject only to axial compression, and no bending occurs. The rigid arch is better able to carry variations in the design loading than is its block counterpart made of individual pieces. Many types of rigid arches exist and are often characterized by their support conditions (fixed, two-hinged, three-hinged).现代建筑中常用的刚性拱，同样是弯曲的阻止拱，但它是由一块连续变形的刚性材料制成的。
如果制成刚性拱的形状，它们可以承受的负载支座仅受轴向压缩的同时并没有发生弯曲刚性拱是能够更好地进行变化的块对应的单件制成的存在许多类型的刚性拱的特点常常是它们的支持条件（固定，双绞链、三铰链）Walls and Plates墙板Walls and flat plates are rigid surface-forming structures. A load-bearing wall can typically carry both vertical loads and lateral loads (wind, earthquake) along its length. Resistance to out-of-plane forces in block walls is marginal. A flat plate is typically used horizontally and carries loads by bending to its supports. Plate structures are normally made of reinforced concrete or steel.墙板 墙壁和平板表面形成的结构是刚性的。
承重墙通常可以进行沿其长度的垂直荷载和侧向荷载（风砌块墙的平面的抵抗力是微不足道的通常用于平板进行水平和通过弯曲其支持负载板结构通常是由钢筋混凝土或刚组成的Horizontal plates can also be made by assembling patterns of short, rigid line elements. Three-dimensional triangulation schemes are used to impart stiffness to the resultant assembly.水平板也可以通过组装短，刚性线的模式三维三角形测量设计是用来赋予所得到的组件的刚度的Long, narrow rigid plates can also be joined along their long edges and used to span horizontally in beam-like fashion. These structures, called folded plates, have the potential for spanning fairly large distances.长，狭窄的刚性板也可以加入和使用到时尚的水平跨越梁中。
这些结构，被称为折叠的板，有可能跨越相当大的距离Cylindrical Shells and Vaults 柱形壳和拱顶Cylindrical barrel shells and vaults are examples of singly curved-plate structure. A barrel shell spans longitudinally such that the curve is perpendicular to the direction of the span. When fairly long, a barrel shell behaves much like a beam with a curved cross section. Barrel shells are invariably made of rigid materials (e.g., reinforced concrete or steel). A vault, by contrast, is a singly curved structure that spans transversely. A vault can be conceived of as basically a continuous arch.柱形壳和拱顶 圆柱型的筒和拱顶都是单独的弧形板式结构的例子。
一个镜筒外壳跨越纵向曲线垂直的方向的弧度当足够长的时候，每筒外壳采用的弧形截面梁很像筒，炮弹等都提出了硬质材料（如钢筋混凝土或钢）相反的，储藏库是一个单独的弧形结构，横向跨越储藏库可以设想基本是是一个连续的拱Spherical Shells and Domes球壳和圆顶A wide variety of doubly curved surface structures are in use .These include structures that are portions of spheres and those that form warped surface (e.g , the hyperbolic paraboloid ). The number of shapes possible is actually boundless. Probably the most common doubly curved structures is the spherical shell. It is convenient to think of this structure as a rotated arch. This analogy, however, is actually misleading with respect to how the structure actually carries loads because of the fact that loadings include circumferential forces in spherical shells which do not exist in arches. Domed structures can be made of stacked blocks or a continuous rigid material (reinforced concrete). Shells and domes are very efficient structures capable of spanning large distances using a minimum of material.球形壳 各种各样的双曲面结构都在使用中，这些包括球部和它所形成的扭曲的表面的结构（例如，双曲抛物线）。
一些可能的形状实际上是无限的也许最常见的双曲面结构是球壳它认为这种结构的旋转拱很方便但是，这个比喻实际上是误导了结构是如何进行负载的因为，载荷包括切线力在球壳中不存在拱门圆顶结构，可以由层叠块或连续的刚性材料（钢筋混凝土）组成壳顶结构是非常有效的，它能够用最少的材料覆盖很大的距离Cables（索）Cables are flexible structural elements. The shape they assume （take on ）under a loading depends on the nature and magnitude of the load. When a cable is simple pulled on at either end, it assumes a straight shape. This type of cable is often called a tie-rod.When a cable is used to span between two points and carry an external point load or series of point loads, it deforms into a shape made up of a series of straight-line segments. When a continuous load （distributed load,）is carried, the cable deforms into a continuously curving shape. The self –weight of the cable itself produces such a catenary curve Suspension cables can be used to span extremely large distances索 索是可弯曲的结构元件。
它们呈现加载的形状取决于负载的性质和严重程度当很简单地拉索的任一端时，它假定了直板造型这种类型的索通常被称为转向横拉杆当索用于跨越两个点之间并进行外部负载或一系列的点荷载，变形的形状由一系列的直线段当进行连续负载（分布荷载），索变形成了连续弯曲的形状索本身的自重产生这样的悬链线，吊索可用于跨越非常大的距离Membranes, Tents, and Nets 膜、 帐篷、网 A membrane is a thin, flexible sheet. A common tent is made of membranes surfaces. Both simple and complex forms can be created using membranes. For surfaces of double curvature, such as a spherical surface, however, the actual surface would have to be made as an assembly of much smaller segments, since most membranes are typically available only in flat sheets. A further implication of using a flexible membrane to create the surface is that it either has to be suspended with the convex side pointing downward or, if used with the convex side pointing upward, supplemented by some mechanism to its shape. Pneumatic, or air-inflated, structures. The shape of the membrane is maintained by the internal air pressure inside the structure. Another mechanism is to apply external jacking forces that stretch the membrane into the desired shape. Various stressed-skin structures are of this general type. The need to pretension the skin, however, imposes various limitations on the shape that can be formed. Spherical surfaces, for example, are very difficult to pretension by external jacking forces, while others, such as the hyperbolic paraboloid, can be handled with comparative ease. 膜、 帐篷、网 是一个薄的膜，柔性板，一个常见的帐篷是由膜表面构成的。
既简单又复杂的形式可以创建使用膜对于双曲率，如球面的表面但是实际的表面将要作为一个组件的更小的段，因为大多数膜通常仅适用于平板用一柔性膜片创建表面的再一个含义是，它要么必须暂停与凸侧朝向下方，或者，如果使用凸侧朝上，通过一些机制来补充其形状充气式膜结构的膜形状是由部的结构的部气压另一种机制是应用外部抬升力，拉伸膜成所需的形状强调皮肤的各种结构的这种通用类型，然而，需要预拉伸皮肤施加各种条件的限制，可以形成的形状球的表面，是非常困难的外部顶力，但是其他的，如双曲抛物面可以比较容易处理Nets are very analogous to membrane skins. By allowing the mesh opening to vary as needed, a wide variety of surface shapes can be formed. An advantage of using crossed cables is that the positioning of the cables mitigates fluttering due to wind suctions and pressures. In addition, tension forces are typically induced into the cables by jacking devices, so that the whole surface is turned into a type of stretched skin. This also gives the roof stability and resistance to flutter.网是非常类似的膜皮，通过使网眼根据需要进行变化，各种各样的表面形状可以形成。
使用交叉索的一个优点是，使索的定位减轻由于风的吸力和压力产生的飘动此外，力通常诱导索顶装置，使整个表面变成一种类型的伸展这也给了顶板稳定性和抗颤性1.2 2.Basic Issues in the Analysis and Design of Structures结构分析与设计中的基本问题 1 Fundamental Structural Phenomena1. 基本结构现象Structure components could break apart or deform badly. The forces causing overturning or collapse come from the specific environmental (e.g., wind, earthquakes, occupancies )or from the self-weight of the form itself. These same applied loadings produce internal force in a structure that stress the material used and may cause it to fail or deform. There are several fundamental ways in which failure can occur.结构组件可以破坏或严重变形，由力的作用造成的倾覆或来自特定的环境（例如，风，地震，占用）再或者是本身的自重的形式。
这些相同的应用负荷产生的力在一个结构中使用的材料可能会导致其变形或失败有几个基本的方法，其中可能会发生故障A first set of concerns deals with the overall stability of a work. As a whole unit, a structure might overturn, slide, or twist about its base, particularly when subjected to horizontally acting wind or earthquake forces. Sliding under its own weight. Overturning or twisting need not be caused only by horizontally acting forces. A work might simply be out of balance under its own self-weight and overturning. The use of wide, rigid foundations helps prevent overturning, as does the use of special foundation elements such as piles capable of carrying tension forces.第一组关注处理工作的整体稳定性。
作为一个整体单元，结构可能会倾覆，滑移，扭转尤其是当风或地震的水平作用时，其自身重量下滑，翻倒或扭转不只是引起水平作用力在自身的重量和倾覆的作用下，可能只是失去了平衡使用宽，刚性的基础，有助于防止倾覆，不使用例如能够携带力桩的特殊要数A second set of concerns deals with internal, or relational, stability. If the parts of a structure are not properly arranged in space or interconnected appropriately, an entire assembly(组装)can collapse internally. Collapses of this type invariably involve large relative movements within the structure itself. Assemblies may be internally stable under one loading condition and unstable under another. Horizontally acting wind or earthquake forces, in particular, cause collapses of this kind. There are several basic mechanisms-walls, frame action, cross bracing –for making an assembly internally stable.第二组关于处理部关系稳定。
如果有部分的结构空间组合不合理，或真个组装不合理，可以适当地相互连接，部折叠这种类型导致的坍塌总是涉及大型结构本身的相对运动组件可能是一个装载条件下部稳定和不稳定的根据项水平因素风或地震尤其会使其坍塌有几个基本的机制墙壁，框架动作，交叉支撑组件的部稳定A third set of concerns deals with the strength and stiffness of constituent elements.There are many structure issues that revolve around the strength of component parts of a structure. These failures, which may or may not lead to total collapse, may be caused by excessive tension, compression, bending, shear, torsional, bearing forces, or deformations that are developed internally in the structure as a consequence of the applied loadings. Associated with each force state are internal stresses that actually exist within the fabric of the material itself. By carefully designing components in response to the force state present, the actual stresses developed in the components can be controlled to safe levels.第三组的关注处理的强度和刚度的结构元素。
很多结构围绕一个结构组成部分的强度问题这些故障可能会导致全面崩溃，可能是由于过度紧，压缩，弯曲，剪切，扭转，轴承，或变形，在结构部开发的应用负荷的后果每个受力状态，实际上存在于物质材料本身的应力通过仔细地设计组件的受力状态，开发组件的实际应力可以被控制到安全水平2. Structural Stability结构稳定性A Fundamental consideration in designing a structure is that of assuring its stability under any type of possible loading condition. All structures undergo some shape changes under load.In a stable structure deformations induced by the action of the load tend to restore the structure to its original shape after the load has been removed. In an unstable structure, the deformations induced by a load are typically massive and often tend to continue increasing as long as the load is applied. An unstable structure does not generate internal forces that tend to restore the structure to its original configuration. Unstable structures quite often collapse completely and instantaneously as a load is applied to them. It is the fundamental responsibility of the structural designer to assure that a proposed structure does indeed form a stable configuration.设计结构的最基本需要考虑的问题，是任何类型的可能负载的条件下确保其稳定性。
所有的结构进行一些稳定结构的变形引起的负载的作用下的形状变化，趋向于回访到初始形状的结构已经被删除在不稳定的结构中，由负载引起的变形通常是大规模的，并且常常施加载荷时，只要继续增加一个不稳定的结构不会产生部的力量，往往恢复到原来的配置结构经常不稳定结构完全折叠和瞬间作为负载被施加到它们身上它的基本结构设计师的责任，以确保建议的结构确实形成一个稳定的配置Stability is a crucial issue in the design of structures that are assemblies of discrete elements. For example, the post-and-beam structure illustrated in figure 1.2a is apparently stable. Any horizontal force, however, tends to cause deformations of the type indicated in figure 1.2b. clearly, the structure has no capacity to resist horizontal load, nor does it have any mechanism that tends to restore it to its initial shape after the horizontal load is removed. The large changes in angle that occur between members characterize an unstable structure that is beginning to collapse. This particular structure will collapse almost instantaneously under load. Consequently, this particular pattern of members is referred to as a collapse mechanism.稳定是一个至关重要的问题，在设计分立元件的组件结构。
例如，梁柱结构示意图1.2a所示显然是稳定的然而，在任何水平方向的力往往会造成在图1.2b的不同变形结构清楚，有没有能力抵抗水平荷载，也没有任何机制，倾向于恢复到其初始形状，水平荷载后删除出现大的变化角度特征不稳定的结构开始崩溃这种特殊的结构将在负载下瞬间崩溃因此，这个特定的图案被称为“崩溃机制”There are really only a few fundamental ways of converting a self-standing structure of the general type shown in figure 1.2a fron an unstable to a stable configuration. These are illustarated in figure 1.2d. the first is to add a diagonal member to the structure. The structure cannot now undergo the parallelogram indicated in figure 1,2b without a dramatic release in the length of the diagonal member (this would not occur if the diagonal were adequately sized to take the forces involved). Another method used to assure stability is through shear walls. These are rigid planar surface elements that inherently resist shape changes of the type illustrated. A reinforced concrete or masonry wall can be used as a shear wall. Either a full or a partial wall can be used (the required extent of a partial wall depends on the magnitudes of the forces involved). A final method used to achieve stability is through stopping the large angular changes between members that are associated with collapse by assuring that the nature of the nature of the connections between members is such that their angular relationship remains a constant value under any loading. This is done by making a rigid joint between members. This is a very common form of joint.真的只有一项独立的通用型数字1.2a不稳定的一个稳定的配置结构转换的一些基本方法。
这些在图1.2d上成为第一个是增加一个对角构件的结构结构现在不能接受对角线的长度（如果对角线有足够大的力量，这种情况不会发生）没有一个戏剧性的释放b图1,2所示的平行四边形用来保证稳定性的另一种方法是通过剪力墙这些平面的表面是刚性的元素本质上所示类型的抗蚀剂形状的变化可用于钢筋混凝土或砖石墙作为剪力墙完整或部分的壁可用于（部分壁所需的程度上依赖于所涉及的力的大小）用于实现稳定的最后一种方法是通过停止大角度变化，确保结构之间的连接的性质就是这样原理的性质，它们的角的关系仍然是一个恒定值这是通过成员之间的刚性连接，是一个非常普遍的形式的联合There are, of course, variants on these basic methods of assuring stability. Still most structures composed of discrete elements rely on one or the other of these basic approaches for stability. More than one approach can be used in a structure (e.g. a structure having both rigid joints and a diagonal), but a measure of redundancy is obviously involved.当然，在这些基本的方法保证稳定的变体。
仍然由分立元件组成的结构依赖于一个或另一个稳定这两种基本方法在一个结构中，可以使用一个以上的方法（例如，具有两个刚性接头和对角线结构），但显然这涉及一定程度的冗余1.2 Determinate and Indeterminate Structures 静定和超静定结构1.2Determinate and Indeterminate Structures静定与超静定结构 Structures are said to be statically determinate when the forces and reactions produced by a given loading can be calculated using only the equations of equilibrium. The simply supported beam shown in Figure 1.3 is statically determinate. We can solve for the three unknown reactions using the equations of equilibrium and then calculate the internal forces such as bending moment, shear force, and axial force at any given location along the length of the beam. 结构被称为静定时的力和反应的一个给定的荷载产生可以只使用平衡方程计算。
简支梁在图1.3所示是静定我们可以解决三未知的反应，利用平衡方程，然后计算等力弯矩，剪切力，和在任何给定的位置沿梁的长度的轴向力 The force method (also called the flexibility method) is used to calculate internal forces and reactions in statically indeterminate structures due to loads and imposed deformations.力法（又称弹性法）是用来计算力和反应静不定结构因荷载和施加变形在力法的步骤The steps in the force method在力法的步骤（1）Determine the degree of statical indeterminacy of the structure. Parameter n will be used to denote the degree of indeterminacy.（1）确定静不定结构的程度参数n可以用来表示不确定性的程度2) Transform the structure into a statically determinate system by releasing a number of statical constraints equal to the degree of statical indeterminacy,n. This is accomplished by releasing external support conditions creating internal hinges. The system thus formed is called the primary system. Number the released constraints from 1 to n. （2）通过释放一些静态约束等于静不定度的结构转化为静定系统，这是通过释放外部支持条件，创建部铰链。
由此形成的系统称为原发性系统编号从1到N的释放的约束 （3）For a given released constraint j, introduce an unknown redundant force Xj corresponding to the type and direction of the released constraint. （3）基本体系沿多余未知力方向的位移应与原结构位移相同 （4）Apply the given loading or imposed deformation to the primary system. Calculate displacements due to the given loading at each of the released constraints in the primary system. These displacements are called Δ1P , Δ2P , ΔnP .., . （4）将给定的加载或主系统的附加变形计算的位移由于在原系统在每个发布约束给定载荷这些位移被称为Δ1P，2PΔ，ΔNP ..， （5）For a given released constraint j, apply a unit load Xj =1 to the primary system. Calculate displacements due to Xj =1 at each of the released constraints in the primary system. These displacements are called （5）对于一个给定的发布约束J，申请单位负载XJ = 1到主系统。
计算的位移由于XJ = 1在每个释放的约束在主系统这些位移被称为，，(6)Solve for redundant forces X1 through Xn by imposing the compatibility conditions of the original structure.These conditions transform the primary system back to the original stru。