举一反三
- For a bar under axial tension, the sections with the maximum normal stress and maximum shear stress are A: the cross section and inclined section with inclined angle 45°, respectively. B: both the cross sections. C: the inclined section with inclined angle 45°and cross section, respectively. D: both the inclined sections with inclined angle 45°.
- The maximum shear stress in the rod in tension and compression is 40MPa, then the maximum normal stress in the rod is equal to . A: 80MPa B: 40MPa C: 60MPa D: 56.6MPa
- The cross section of a straight beam remains plane when the beam deforms due to bending. This causes ( ) on one side of the beam and ( ) on the other side. The neutral axis is subjected to ( ) .? normal stress; shear stress; zero stress|tensile stress; compressive stress; zero stress|compressive stress; tensile stress; maximum normal stress|shear stress; normal stress; zero stress
- If the normal stress on the cross section of the axial tensile rod is σ, then the normal stress and shear stress on the 45° degrees section are .
- When the soil reaches the limit equilibrium state, the location of shear failure surface must be on the maximum shear stress surface（ ）
内容
- 0
In Mohr-Coulomb failure criterion, failure occurs when the ______ is achieved and not when the maximum shear stress is achieved.
- 1
In axial tension, the ratio of axial stress to strain is always constant( ).
- 2
Which of the following statements is correct ? (1) There are two types of stress, normal stress(σ) and shear stress(τ). (2) On one section, the normal stress(σ) and the shear stress(τ) must be perpendicular to each other. (3) On one section, all the normal stress(σ) must be equal in size and same in the direction. (4) On one section, all the shear stress(τ) must be parallel.
- 3
According to Maximum Principal Stress theory (also known as Rankine's theory of failure), elastic failure occurs ( ) A: when the minor principal stress is equal to the elastic limits value in a simple tension test B: when the greatest principal stress reaches the elastic limit value in simple tension test C: when the greatest principal stress is equal to the stress corresponding to the upper yield limit in a tension test D: none of the above
- 4
The general three-dimensional state of stress at a point can be represented by an element oriented so that only ( ) act on it. A: three principal stresses B: two principal stresses and one shear stress C: six principal stresses D: three absolute maximum shear stresses