The adjusted amplilude of dynamic tensile stress in beam direction under installation of both springs and dampers in arch di- rection for the dam with one joint and the dam with three joint ranges over -2.846 - -4.273MPa and -2.482 - -4.692MPa, respectively.

continuous curved box girder bridge relied to the structure form: because of the beam’s curvature radius, the deadweight and prestress force caused the curved box girder’s torsional distortion, added the actions of the temperature grads and vehicle, the outward torsional distortion turn worse, some time caused some inside bearings’ appear negative vertical reaction.

From this analysis the internal force is reduced along cantilever direction and the internal force is increased along arch direction, when the physical mechanical index is reduced along cantilever direction and it is not changed along arch direction.

It showed that when strong earthquake happens, the repetitive open and close of transverse expansion joints would cause obvious re-distribution of dam stress which greatly reduce the arch tensile stress around the cracked areas so that the beam tensile stress would be increased on the downstream surface of the middle dam body.

The present method is applied to stress analysis for a typical cylindrical arch dam, and the calculated results of the arch stress and hoop stress conform to those obtained by the trial load method. Therefore, the calculated results of the arch dam stress by the present method can be used for safety assessment of arch dams according to the national arch dam design code.

The equation for calculation is established based on the assumptions that the stress is linearly distributed in the arch-beam direction, the equivalent stress on the upstream and downstream surfaces are unknown variable and the constraint internal force in the cross section of arch or beam is given. The formulas for calculating other stress components at the upstream and downstream surface of the dam are deduced when boundary conditions are given.

The system described is applicable to both a direct change in the laser-beam direction in space and the control of the position of a target exposed to laser radiation.

Estimating dimensions of flaws with narrow openings along the beam direction

The problem of flaw dimension measurement along the beam direction is discussed from the viewpoint of the measurement accuracy.

Practical recommendation are put forth for estimating dimensions of flaws with small openings, such as incomplete fusions in welded joints, along the beam direction using X-ray photographs.

When a light beam propagates perpendicularly to colored lamellas, the dichroism is much larger and the birefringence is smaller than in the case where the beam direction is parallel to lamellas.

This is a preliminary study of the effect of vertical curvature on the cantilever and arch stresses in a double-curvature arch dam. A modification of the conventional method of crown cantilever is proposed with the consideration of the adjustment of vertical displacements, in additon to the radial displacements at the crown of arches. Results of the study indicate that, if the vertical curvature is properly chosen, tensional stresses in the crown cantilever of the dam can be reduced to a certain extent. Experimental...

This is a preliminary study of the effect of vertical curvature on the cantilever and arch stresses in a double-curvature arch dam. A modification of the conventional method of crown cantilever is proposed with the consideration of the adjustment of vertical displacements, in additon to the radial displacements at the crown of arches. Results of the study indicate that, if the vertical curvature is properly chosen, tensional stresses in the crown cantilever of the dam can be reduced to a certain extent. Experimental study had been made with the aid of gelatin models. Analysis of the results showed that, except in the vicinity of the top of the dam, the general trend of the distribution of arch and cantilever stresses agreed with that of computation within reasonable limits.

The dynamic behavior of an arch-gravity dam during earthquakes is determined by the gelatin-model dynamic test, gypsum-model dynamic test and the approximate analysis. These results are fairly comsistent. The appr- oximate analysis method proposed in this paper is to determine the dynamic behavior of the entire dam from the dynamic behaviors of some vertical cross sections. The natural frequencies, modal shapes and the stresses of the dam with reservoir full are determined in terms of those yolues with reservoir...

The dynamic behavior of an arch-gravity dam during earthquakes is determined by the gelatin-model dynamic test, gypsum-model dynamic test and the approximate analysis. These results are fairly comsistent. The appr- oximate analysis method proposed in this paper is to determine the dynamic behavior of the entire dam from the dynamic behaviors of some vertical cross sections. The natural frequencies, modal shapes and the stresses of the dam with reservoir full are determined in terms of those yolues with reservoir empty by the perturbation method.

The diameters and projection area of the articular surfaces, contributed to the formation of the sacroiliac joint, were determined on 50 sets of pelvic bones with image analysing apparatus.By drawing a line connecting the most anterior point of the prominence to the deepest point of the posterior incisure, the articular surface may be divided into a superior and an inferior portions. The inferior portion was larger than the superior portion. Each portion of the articular surface on the ilium is slightly larger...

The diameters and projection area of the articular surfaces, contributed to the formation of the sacroiliac joint, were determined on 50 sets of pelvic bones with image analysing apparatus.By drawing a line connecting the most anterior point of the prominence to the deepest point of the posterior incisure, the articular surface may be divided into a superior and an inferior portions. The inferior portion was larger than the superior portion. Each portion of the articular surface on the ilium is slightly larger than that on the sacrum.In order to explore the relationship between the form of the articular surface and its function in transmitting the gravity of the human body, the stress of the neighbouring area near the anterior margin of the articular surface was determined. Moreover, the bony architecture on the cross section passing through the articular surface was observed. It suggests that the strain in the neighbouring area was in linear equation with the gravity loaded on the spinal column. The strongest stress was determined at the anterior margin of the anterior prominence and the thickness of the cortex lying on the relevant bones appears most obvious at the same sites. These results further improve that the bony architecture was consistent with the strain in bearing the body weight. Besides, the form of the articular surface was also adapted to its function.