The designing material and the construction material is also analysed. And the stress distribution is calulated through SAP84 Finite Element Analysis System. The major reason of the accident is the lack of knowledge of computation theory and joint structures,so there is large stress in the joint zones.

as (σ_1-σ_3)≈(σ_1-σ_3)_c, the sliding plane originally with asperity has been flattened relatively, and after that, the sudden instability with large stress drop and violent shock occurs.

Using the scattering theoretical approach based on the semi-empirical tight binding Green function method, we identified the large stress anisotropy as the primary driving force of defects on Sb/Si(001) (Chapter 3).

The large stress twisting intelligent instrument to measure the damping property of metal material is an important testing equipment for researching the high-damping alloy.

We suggest that the concentration of large stress drop values at 10-36km depth may be related to the large stress/strain associvated with a brittle, competent intrusive body of mafic nature.

Looking at the average stress field we see a large stress concentration left at the edge of the large events, out of which the future events emerge.

However, large events in the nonconservative uniform automaton and in the fractal systems produce large stress perturbations that move the system out of the critical state.

Six events with large stress drop are located within a previously suggested asperity, and seven more suggest a boundary zone at the intersection of the Petatlan and Zihuatanejo aftershock rupture volumes.

The wave may accumulate at the focusing point and give rise to very large stress magnitudes, even though the initial stresses may be relatively small.

This paper recommands the design method of Dandong Shahe large bridge and the calculation results. The dynamic analyses of the large-spanned arch bridge and the related problems of the earthquake-proof construction design is explicated.We have the following views:1. Because of the curvature of the arch axis and the effect of the elastic compression, the effect of the vibration couplings of the orthogonal directions in the arch plane is very obvious. 2.When the earthquake sets on the arch plane,there...

This paper recommands the design method of Dandong Shahe large bridge and the calculation results. The dynamic analyses of the large-spanned arch bridge and the related problems of the earthquake-proof construction design is explicated.We have the following views:1. Because of the curvature of the arch axis and the effect of the elastic compression, the effect of the vibration couplings of the orthogonal directions in the arch plane is very obvious. 2.When the earthquake sets on the arch plane,there will be considerable strain on the lower edges of the arch springings. This is in agreement with the damage phenomenon of the arch axis. Large stress and strain may occur from L/4 to the arch crown. 3. When the earthquake acts outside the arch plane, a very large horizontal displacement and torsional moment will occur in tee arch rib. In Tongshan earthquake two lower bearing tyqe arch bridges collapsed. This was the consequence of the horizontal earthquake action. 4. The effect of the vertical earthquake component is quite big. It should not be neglected in the earthquake-proof construction design. 5. The maximum type parameters and coefficients may occur in the higher-order vibration type, therefore, if we merely make computations for the earthquake-proof construction design of the large-spanned arch bridge of the first vibration type, it may not be safe and sound. 6. There is the apparent effect of the earthquake hypogene to the arch bridge earthquake by the frequency spectrum of the earthquake wave. Therefore, we consider that it is apt to proceed the overall computations for the aseisma tic constructions by means of the dynamic analysis in dealing with the large-spanned arch bridge.

This paper deals with contact stress for specimens of different shapes (rectangle, trapezoid, sphere) using the three- dimensional photoelastic method. The specimens are recommended according to the temporary rule of the testing method for the contact fatigue testing machine(JPM— 1 and JP—BD) . The distributive case of stresses can be obtained. After the experimental and calculative results are compared, It is suggest that the spherical specimen is adopted as standrad specimen. Its advantages are:...

This paper deals with contact stress for specimens of different shapes (rectangle, trapezoid, sphere) using the three- dimensional photoelastic method. The specimens are recommended according to the temporary rule of the testing method for the contact fatigue testing machine(JPM— 1 and JP—BD) . The distributive case of stresses can be obtained. After the experimental and calculative results are compared, It is suggest that the spherical specimen is adopted as standrad specimen. Its advantages are: (1) The request isn't severe to experimental condition and the comparability of experimental results is good. (2) The spherial specimen is typical because it is similar to the shape of most parts that is subjected to fatigue failure in engineeing practice (3) A small force exerted on the specimen can produce a comparatively larger stress . So the useful life of loading axis can be prolongeol

The large stress twisting instrument to measure the damping property of metal material is an important testing equipment,for researching the highdamping alloy.Up till now it hasn't been produced in our country,and hasn't been finalized abroad either.In this paper,the writers have explored some questions of measuring mechanism,probe,mechenical model of singlefree swing,interference and how to restrain it.For this reason,the idea of designing the whole instrument and the key of technology in eaeh link have...

The large stress twisting instrument to measure the damping property of metal material is an important testing equipment,for researching the highdamping alloy.Up till now it hasn't been produced in our country,and hasn't been finalized abroad either.In this paper,the writers have explored some questions of measuring mechanism,probe,mechenical model of singlefree swing,interference and how to restrain it.For this reason,the idea of designing the whole instrument and the key of technology in eaeh link have been expounded.