The torsion resistance of the tension bar and the calculatiolls of bending shear stress, free torsional shearstress and bending torsional shear stress on the section are also discussed.
性质：用圆柱形材料试件作抗扭实验可求得扭矩和扭角的关系，相应最大扭矩的最大剪断应力叫抗扭强度。
2
The theoretical background of equivalence principle is briefly given, and the experimental tests of the equivalence principle is discussed in detail, via free-fall method and torsion balance.
Both the gravitational gauge field equations for leptons and the gauge field equations of strong gravity for hadrons have been obtained in the torsion and the torsion-free cases respectively.