non-porous 无孔的 isotropic 各向同性 deformation 变形
Through material mechanics courses, students should be able to calculate the stiffness and the strength, when simple deformation comes on the straight bar in pulling, pushing, cutting, twisting, bending； to calculate the stress and strength, when skew bending, eccentric compression (tension), bending and torsion comes on the combined deformation; to understand the purposes and ways of the basic experiments.
"Building mechanics" is studied about the working condition of the structures and components applied the loads or other factors, which is the strength, stiffness and stability of buildings. It is a very wide range of areas, including theoretical mechanics, material mechanics, structural mechanics, elastic mechanics, plastic mechanics, structural dynamics, and so on. As for the Building Engineering College students, our focus is on theoretical mechanics, material mechanics and structural mechanics, known as three mechanics.
statics kinematics dynamics
静力学 运动学 动力学
Statics mainly studies the balance of objects acted forces on, and how to create the balance conditions under various force systems. At the same time, statics is also the basic methods, by which to study the simplification of the force system and the mechanical analysis of the object.
destruction law
破坏机制
Ignoring secondary factors, simplifying and abstracting components, the following basic assumptions are given in material mechanics: 1. Continuity assumption - a material is continuous and nonporous; 2. Uniformity assumption - a material shows the same nature in different parts; 3. Isotropic assumption -a material shows the same nature in different directions; 4. Small deformation assumption — the deformation of a material is far smaller than the size of components, so as to calculating under the original size and geometry.
stress eccentric
应力 偏心的
Fig 6.2 Ｍ andＶ in bending
Structural mechanics
It is a discipline major to study the law of structures bearing and transferring loads, and how to optimize the structure. Here, the structure means the system that can bear and transfer loads, including rods, plates, shells and their combinations, such as bridges, roof trusses and loadbearing walls, and so on[2].
After theoretical mechanics courses, students should be able to abstract the simple practical problems in practice work to the static model to analyze the balance and the force of the objects; to carry out the calculation about general force systems; to analyze a simple movement about a point or a rigid body.
the virtual displacement principle 虚位移原理
In engineering, the statics shares a wide range of applications, for example, the analysis of houses and bridges, the analysis and calculation of loads, etc. The statics also is known as a foundation of material mechanics and structural mechanics.
rigid body Justice
刚体 公理
According to the research methods, statics can be divided into the geometric statics and the analytic statics. Applying the geometric statics, we can use analytical method or graphic method to study the static problems. While, we can base the analytic statics on the virtual displacement principle and know the analytic way as the major research means[1]. It established general roles of the balance of arbitrary force systems; therefore, the analytic statics is more common approaches.
roof truss
屋架
The main task of structural mechanics course is to study the laws of stress, strain and displacement, when the loads are acted on the structures; to analyze engineering structures, who are made up of different materials or forms, in order to provide analytic methods and calculable formulas for engineering design; to identify the ability of bearing and transferring loads; to research and develop new type engineering structures.
There are three basic static physical parameters: force, couple and moment.
couple moment
力偶 力矩
The almost full content of statics is deduced on the base of several Justices. The Justices, who are known as the summary of the knowledge accumulated by peoples in the production of long-term practice, reflects the simplest and basic attribute of the force acting on the rigid body. The accuracy of these can be verified by experiment, but not be proved by the more fundamental principles.