New Analysis Based on Unit Body Balance and Its Particle Balance Problem - The Basic Contradiction and New Analysis of Current Elasticity Theory

This paper discovered a new concept that the unit balance and particle balance are not equivalent. Based on the research of tensile of uniform section bar, it indicated that the normal stress and shear stress on oblique section can only make sure partly body balance while not every particles. The value of and is less than the equilibrium stress of particles. Besides, the particle balance stress is times of the unit balance stress in the state of pure extension. The extreme stress is not the principal stress of cell body but the balance stress of particle. Using this formula, the problem existed for 350 years that the stretch-shear act on a bar is easer destroyed relate to the compress-shear acted can be explained perfectly. What’s more, this theory has also been validated in the Damage Mechanics National Key Laboratory of Tsinghua University. The error between this theory and actual is only 1%, while based on three and fourth strength theory, the errors are 14.2%, 18.2% respectively. It’s also the root cause of large bridge collapse.