Mechanics of materials is a branch of applied mechanics that deals with the  behavior of solid bodies subjected to various types of loading. Other names for  this field of study are strength of materials and mechanics of deformable bodies.  The solid bodies considered in this book include bars with axial loads, shafts in  torsion, beams in bending, and columns in compression. The principal objective of mechanics of materials is to determine the stresses,  strains, and displacements in structures and their components due to the loads  acting on them. An understanding of mechanical behavior is essential for the  safe design of all types of structures, whether airplanes and antennas, buildings  and bridges, machines and motors, or ships and spacecraft. That is why mechanics of materials is a basic subject in so many engineering fields. Most problems in  mechanics of materials begin with an examination of the external and internal  forces acting on a stable deformable body. First the loads acting on the body are  defined, along with its support conditions, then reaction forces at supports and  internal forces in its members or elements are determined using the basic laws  of static equilibrium (provided that the body is statically determinate).

In mechanics of materials you study the stresses and strains inside real bodies, that is, bodies of finite dimensions that deform under loads. To determine the  stresses and strains, use the physical properties of the materials as well as numerous theoretical laws and concepts. Mechanics of materials provides additional  essential information, based on the deformations of the body, to solve statically  indeterminate problems (not possible using the laws of static equilibrium alone).

Theoretical analyses and experimental results have equally important roles  in mechanics of materials. Theories are used to derive formulas and equations  for predicting mechanical behavior but these expressions cannot be used in  practical design unless the physical properties of the materials are known.  Such properties are available only after careful experiments have been carried out in the laboratory. Furthermore, not all practical problems are amenable  to theoretical analysis alone, and in such cases physical testing is a necessity. 

Mechanics of Materials is a basic engineering subject that, along with statics, must be understood by anyone concerned with the strength and physical performance of structures, whether those structures are man-made or natural. At the college level, statics is usually taught during the sophomore or junior year  and is a prerequisite for the follow-on course in Mechanics of Materials. Both courses are required for most students majoring in mechanical, structural, civil,  biomedical, petroleum, nuclear, aeronautical, and aerospace engineering. In addition, many students from such diverse fields as materials science, industrial  engineering, architecture, and agricultural engineering also find it useful to study mechanics of materials.

另行通知。

An essential prerequisite for success in a first course in mechanics of  materials is a strong foundation in statics, which includes not only understanding fundamental concepts but also proficiency in applying the laws of static equilibrium to solutions of both two- and three-dimensional problems.

《材料力学》第四版 刘鸿文主编

《Mechanics of Materials》9th Edition