Based on concept of endochronic theory and “plastic stress”, a new endochronic constitutive equation of soft rock is obtained by using the four groups of internal variables which represent different laws of displacement of soft rock. Compared with the experimental results the theoretical prediction is satisfactory.

In offshore soils there exists widely a kind if soil which mainly consists of silt and sand except clay with low plasticity. It is often considered a bearing layer of foundation. In this paper this kind of soil in the area of the south china sea where a gravity platform is to be constructed, is studied in the three cases: (1) behavior of static CU; (2) behavior under cyclic loading; (3) behavior of static CU after the soil has been cyclied. According to these laboratory results the mechanism is presented and discussed to explain its special mechanical behaviors

The two-dimensional nonlinear FEM results for Ertan project were introduced in this paper, which were analyses on the section 0+679m of the diversion tunnel on the right bank. The influence of the variation of rock properties on the stability of the tunnel and the role of step-by-step excavation and shotcrete and rock bolting were emphasized here. Some suggestions on construction were given. The paper is useful to the preliminary designs and construction for the diversion tunnel on the right bank.

This paper has done the spectrum analysis of deformity waveform and it’s each frequency element is rectified with measuring system frequency response curve by positive and inverse Fourier transform theoretical. If all of rectified frequency elements of waveform are superposed then real waveform would be obtained. This paper has done theoretical analysis and a practical method is introduced.

On the basis of the spectral analysis of blast and vibration waveforms, a review on the current methods of spectral estimation and their results is presented. The spectral features of blast signals are given as well.

For the purpose of in conjunction with the usage of the RSM-08 instantaneous signal processor, which was developed and made by our institute, useful software has been designed. In which the theory and methods of “digital signal analysis” have been applied. To the realized program, such as time measuring and amplitude measuring of acoustic waves, stress-strain analysis and microcomputer communication etc. , have been introduced. Also special stress has been laid on the introduction of the structure, algorithm and programming of data acquisition and processing program.

In this paper, the progress of rock mechanical test techniques, theoretical explorations and their applications in hydraulic engineering in China is reviewed. Some discussions and suggestions about their future development are given as well.

When in Institute of Soil and Rock Mechanics, Karlsruhe University, Federal Germany, the author of this paper performed some cyclic loading tests on the large-sized triaxial testing machine developed in this institute. The rock sample used were 60cm in diameter and 120cm in height. The work mainly included the study of deformation and strength behavior of the samples and was based on the viewpoint of analyzing the irreversible deformation. Under cyclic loading, although the irreversible deformation generally increased with the n umber of cycles, the deformation trends obtained at various stress levels distinctly differed from each other. At low stress levels a comparatively large irreversible deformation arouse from the first few cycles of loading. With the increase of the number of cycles its growth decayed gradually and tended finally to a stable constant value. When the stress level reached a certain “threshold” value, the situation became entirely different. The increase of the number of cycles caused an acclecrated growth of the irreversible deformation till a complete failure of the whole sample. The test results also illustrated that this characteristic stress value was slightly lower than the so-called “yield” value. The study of such a characteristic value is of great importance for under-standing the mechanical properties of rock masses under cyclic loading. The experimental curves of irreversible deformation vs. the number of cycles show a remarkable resemblance to corresponding rheological curves, which, perhaps, may not be accidental. It is propose in this paper that the relation of the strength obtained in conventional tests, the long-term strength in rheological tests and the strength under cyclic loading should be studied. Undoubtedly, it is significant for evaluating the strength and safety factor in rock engineering problems.

The correlations of sound wave velocities and physical properties of quartz sand with different grain size were investigated through laboratory tests. Emphases were put on studying the relationship between density, water content and longitudinal and shear wave velocities. The equations which show the correlation of density, void ratio and longitudinal and shear wave velocities, and with water content as a parameter are given in this paper. In addition, the monotonic relations of density, void ratio and sound wave velocities for sands with different water content are also presented.

In southern China, there are a great amount of red clay(laterite) which contains some free ferric oxide. Owing to its composition and microstructure developed under hot, wet soil-forming conditions, the clay has several special characteristics. Although the water content and void ratio of laterite are greater than similar clay soils, its strength is still higher than the others. There seems to be a contradiction between its physical parameters and mechanical properties. In this paper, the effect of free ferric oxide in laterite on its engineering properties, such as strength, swelling properties and others is discussed. The research result shows that special properties of laterite are the result of various conditions of formation, loss and crystallization degree of free ferric oxide, and its physical and mechanical properties will change with variation of physicochemical circumstance.

In this paper, on the base of a detailed survey into the rockfall and the landslide of Majiaba slope, the mechanical mechanism of the rockfall and the landslide is analyzed by inversion method. The stabilities of Majiaba slope both before and after the landslide are evaluated, and the preventive and corrective measures are given. The theoretical results are consistent with the practical situation.

This paper deals with the method of bearing test on dynamic compacted bases and the characteristics of the bases. The test results show that the bases have two-stratum structures. For this reason, attentions must be paid to distribute locations of the test at different depths and to do some computer verifications for the underlying soft stratum.

A fast loading technique of soft rocks and an automatic data processing system used in the experiments are presented in this paper. Research results demonstrate that the 10t fast loading equipment is applicable to study on dynamic mechanical properties of soft rocks under medium strain rate. By using an automatic data processing system, a group of curve which reflect the relations between some physical parameters, such as σ-ε and σ-t，can be drawn by a plotter, so that the period of experiment can be reduced, and more accurate results can be expected.

The response of long bolts in weathered and fractured granite under blasting was experimentally studied. The opening supported with long bolt and shotcret was chosen for the design, which was examined by monitoring stress states and particle vibrations round the opening during blasting. Borehole TV, sonic wave method and macro investigation were also used to determine fracture features post blasting. Neither falling rock nor bulging on bottom were found. The long bolt strengthened opening has proved to have good support effects and excellent response against blasting, compared with neighbouring unlined or short bolting opening.

The in-situ elastic wave tests and the main results of the quality of the grouting project for the foundation consolidation in Gezhou Dam construction site were presented. It has been shown that the in-situ elastic wave test is an advanced, efficacious and economical method to test and evaluate the quality of grouting project for foundation consolidation in important and large scale of hydroelectrical projects.

This paper investigates wave propagation and its interaction with discontinuities in media using numerical models which employ a finite difference method. The paper has two parts, the first of which considers wave propagation and scattering by simulating a compressive body source in a 2-D half-space containing a step or a slot on the surface, which represents a cliff or a rift valley that has dimensions of the order of the wavelength in the source. The second part of the paper reports a hybrid technique which combines a perturbation method and the finite difference method for wave propagation again caused by the body source in a 2-D half-space system but with a shallow surface obstacle, such as a smoothed ridge, with elastic constants slightly different from bulk material and the slops of the topography being shallow. This hybrid technique is also reported being applied to a half-space with a horizontal insert or void. Results obtained are of importance in both theoretical studies on wave propagation and interaction and applied researches on the analysis and isolation of the damage caused by seismic waves.

Strength and deformability of rock under cyclic loading were experimental studied. It was found that the strength under cyclic loading is lower than that under static loading, and that cyclic fatigure strength is related to amplitude and frequency. Also, it was found that the deformation of rock under fatigure loading is like that in creep test.

Offshore vane shear and penetration tests in situ were conducted in San Zao Bay near the pearl river mouth and systematic results of vane strength Cu and specific penetration resistance Ps were obtained. The specific penetration resistances and vane strength increase with the increase of depth, from which the formula, Cu = 0.0069h and Cu=0.0024Ps were derived. These conclusions provided the design bases for building the embankment in San Zao Bay. Also the method of offshore tests was improved according to the in-situ test conditions and a convenient and economical technique of offshore test for the similar engineering was given.

In this paper, strength theory of materials is researched according to the relative law of elastic and plastic deformations. A new strength theory is presented. There is a satisfactory coincidence between the theory and experiment results.

The measuring principle, structure feature, specificity criterion, error analysis and its application in-situ of tape WRM-4 extensometer are introduced in this paper.