剪力争(国外英文资料).doc

剪力图(国外英文资料) 7 § 3 shear diagram and bending moment diagram One, the shear equation and the bending moment equation Under normal circumstances, the beam shear and moment on the cross section in the value is different, shear force and bending moment are the changes over the axis of the beam position, assume that the coordinates of the location of the cross section along the axis of the beam with said, shear force and bending moment on the cross section can be written in function, namely: The equation of shear force and bending moment along the axis of the beam axis are called the shear equation and the bending moment equation. Two, shear diagram and bending moment diagram In order to more image to express the changing rule of the shear and bending moment along the beam axis, usually use graghs them, said the change rule of shear force and bending moment along the beam axis graphics, known as the shear diagram and bending moment diagram, respectively. When drawing the shear diagram and bending moment diagram, the shear equation of the beam and the bending moment equation are usually written, then the shear diagram and the bending moment diagram are drawn according to the equation. In the drawing graph, the horizontal cross sectional area is represented by the horizontal coordinate, and the value of the shear force and bending moment of the corresponding section is indicated by the vertical coordinate. The cutting force and bending moment are above the shaft, the negative shear force and bending moment are drawn under the shaft, and the following examples illustrate the drawing method of the shear diagram and the bending moment diagram. Example 7-3, as shown in figure 7-12a, the cantilevered beam, the free end of the concentrated force, try to write the shear equation of the beam, the bending moment equation, and draw the shear diagram and the bending moment diagram. Solution: the equation of shear force and bending moment equation Is due to the cantilever beam, can ne