【文章內(nèi)容簡(jiǎn)介】 able under another. Horizontally acting wind or earthquake forces, in particular, cause collapses of this kind. There are several basic mechanismswalls, frame action, cross bracing –for making an assembly internally stable.第二組關(guān)于處理內(nèi)部關(guān)系穩(wěn)定。如果有部分的結(jié)構(gòu)空間組合不合理，或真?zhèn)€組裝不合理，可以適當(dāng)?shù)叵嗷ミB接，內(nèi)部折疊。這種類(lèi)型導(dǎo)致的坍塌總是涉及大型結(jié)構(gòu)本身的相對(duì)運(yùn)動(dòng)。組件可能是一個(gè)裝載條件下內(nèi)部穩(wěn)定和不穩(wěn)定的根據(jù)項(xiàng)。水平因素風(fēng)或地震尤其會(huì)使其坍塌。有幾個(gè)基本的機(jī)制墻壁，框架動(dòng)作，交叉支撐組件的內(nèi)部穩(wěn)定。A third set of concerns deals with the strength and stiffness of constituent are many structure issues that revolve around the strength of ponent parts of a structure. These failures, which may or may not lead to total collapse, may be caused by excessive tension, pression, 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 ponents in response to the force state present, the actual stresses developed in the ponents can be controlled to safe levels.第三組的關(guān)注處理的強(qiáng)度和剛度的結(jié)構(gòu)元素。很多結(jié)構(gòu)圍繞一個(gè)結(jié)構(gòu)組成部分的強(qiáng)度問(wèn)題。這些故障可能會(huì)導(dǎo)致全面崩潰，可能是由于過(guò)度緊張，壓縮，彎曲，剪切，扭轉(zhuǎn)，軸承，或變形，在結(jié)構(gòu)內(nèi)部開(kāi)發(fā)的應(yīng)用負(fù)荷的后果。每個(gè)受力狀態(tài)，實(shí)際上存在于物質(zhì)材料本身的內(nèi)應(yīng)力。通過(guò)仔細(xì)地設(shè)計(jì)組件的受力狀態(tài)，開(kāi)發(fā)組件的實(shí)際應(yīng)力可以被控制到安全水平。2. Structural Stability結(jié)構(gòu)穩(wěn)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 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 pletely 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.設(shè)計(jì)結(jié)構(gòu)的最基本需要考慮的問(wèn)題，是任何類(lèi)型的可能負(fù)載的條件下確保其穩(wěn)定性。所有的結(jié)構(gòu)進(jìn)行一些穩(wěn)定結(jié)構(gòu)的變形引起的負(fù)載的作用下的形狀變化，趨向于回訪(fǎng)到初始形狀的結(jié)構(gòu)已經(jīng)被刪除。在不穩(wěn)定的結(jié)構(gòu)中，由負(fù)載引起的變形通常是大規(guī)模的，并且常常施加載荷時(shí)，只要繼續(xù)增加。一個(gè)不穩(wěn)定的結(jié)構(gòu)不會(huì)產(chǎn)生內(nèi)部的力量，往往恢復(fù)到原來(lái)的配置結(jié)構(gòu)。經(jīng)常不穩(wěn)定結(jié)構(gòu)完全折疊和瞬間作為負(fù)載被施加到它們身上。它的基本結(jié)構(gòu)設(shè)計(jì)師的責(zé)任，以確保建議的結(jié)構(gòu)確實(shí)形成一個(gè)穩(wěn)定的配置。Stability is a crucial issue in the design of structures that are assemblies of discrete elements. For example, the postandbeam structure illustrated in figure is apparently stable. Any horizontal force, however, tends to cause deformations of the type indicated in figure . 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.穩(wěn)定是一個(gè)至關(guān)重要的問(wèn)題，在設(shè)計(jì)分立元件的組件結(jié)構(gòu)。例如。然而。結(jié)構(gòu)清楚，有沒(méi)有能力抵抗水平荷載，也沒(méi)有任何機(jī)制，傾向于恢復(fù)到其初始形狀，水平荷載后刪除。出現(xiàn)大的變化角度特征不穩(wěn)定的結(jié)構(gòu)開(kāi)始崩潰。這種特殊的結(jié)構(gòu)將在負(fù)載下瞬間崩潰。因此，這個(gè)特定的圖案被稱(chēng)為“崩潰機(jī)制”There are really only a few fundamental ways of converting a selfstanding structure of the general type shown in figure fron an unstable to a stable configuration. These are illustarated in figure . 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 mon form of joint.。成為第一個(gè)是增加一個(gè)對(duì)角構(gòu)件的結(jié)構(gòu)。結(jié)構(gòu)現(xiàn)在不能接受對(duì)角線(xiàn)的長(zhǎng)度（如果對(duì)角線(xiàn)有足夠大的力量，這種情況不會(huì)發(fā)生）沒(méi)有一個(gè)戲劇性的釋放b圖1,2所示的平行四邊形。用來(lái)保證穩(wěn)定性的另一種方法是通過(guò)剪力墻。這些平面的表面是剛性的元素本質(zhì)上所示類(lèi)型的抗蝕劑形狀的變化?？捎糜阡摻罨炷粱虼u石墻作為剪力墻。完整或部分的壁可用于（部分壁所需的程度上依賴(lài)于所涉及的力的大?。?。用于實(shí)現(xiàn)穩(wěn)定的最后一種方法是通過(guò)停止大角度變化，確保結(jié)構(gòu)之間的連接的性質(zhì)就是這樣原理的性質(zhì)，它們的角的關(guān)系仍然是一個(gè)恒定值。這是通過(guò)成員之間的剛性連接，是一個(gè)非常普遍的形式的聯(lián)合。There are, of course, variants on these basic methods of assuring stability. Still most structures posed 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 (. a structure having both rigid joints and a diagonal), but a measure of redundancy is obviously involved.當(dāng)然，在這些基本的方法保證穩(wěn)定的變體。仍然由分立元件組成的結(jié)構(gòu)依賴(lài)于一個(gè)或另一個(gè)穩(wěn)定這兩種基本方法。在一個(gè)結(jié)構(gòu)中，可以使用一個(gè)以上的方法（例如，具有兩個(gè)剛性接頭和對(duì)角線(xiàn)結(jié)構(gòu)），但顯然這涉及一定程度的冗余。 Determinate and Indeterminate Structures 靜定和超靜定結(jié)構(gòu) and Indeterminate Structures靜定與超靜定結(jié)構(gòu) Statically Determinate Structures超靜定結(jié)構(gòu) 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 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. 結(jié)構(gòu)被稱(chēng)為靜定時(shí)的力和反應(yīng)的一個(gè)給定的荷載產(chǎn)生可以只使用平衡方程計(jì)算。我們可以解決三未知的反應(yīng)，利用平衡方程，然后計(jì)算等內(nèi)力彎矩，剪切力，和在任何給定的位置沿梁的長(zhǎng)度的軸向力。 Force Method 力法 The force method (also called the flexibility method) is used to calculate internal forces an