In this paper, the main influence factors upon bearing capacity of friction piles are discussed, load transfer mechanism of piles is analyzed, various kinds of load transfer functions are described, determination methods for lateral friction and tip resistance of piles are introduced, and some field measuring results are presented. Then, the effects of piles driving methods on bearing capacity are analyzed. Finally, the subsidence, unsteady and bearing capacity variations of bored concreting pile are discussed.

The auto-march-extruding perforator in soil stratum is an equipment for geotechnical construction, which has a shape as a shell. The perforator extrudes and passes through the soil stratum, then a hole is made. The perforation diameter, speed as well as the power supply required are closely related to physical and mechanical properties of soil stratum. In this paper, the design principles, structures and applications of the perforator. The engineering applications showed that this perforator has many advantages, for examples, simple in structure and operation, applicable for various kinds of soil stratum.

In this paper, we performed contrast analysis of various kinds of geostress measuring methods, and inspected Glotzi pressure cell. On three directions(0°, 45°, 90°), the modellings of stress measurements were conducted with CYG-00 hydraulic stressometer. We firstly suggested the method of directly measuring stress in weak rockmass with hydraulic boring stressomete, which consisted of three hydraulic stressometer. The structure principle and operating method of hydraulic boring stressometer were introduced. In addition, some modelling results of stress measurement with this stressometer were presented.

In this paper, the results of measuring various vibration sources at industry complexes are described. Regarding velocity and displacement as the control values, the vibration-proof distance are given for plans of various industry complexes. In addition, soil’s energy absorb coefficients and conversion coefficients of different soils are also presented for determining vibration-proof distance.

In this paper, the important double layer parameters of Na-Kalinite including its ζ-potential and conductivity at different PH were determined with the streaming potential method, and its structure features at different conditions of double layer were compared and analyzed. The results showed that consolidation pressure, pore water pressure, ζ-potential and conductivity of clay vary with its PH.

In this paper, the experimental study on the uniaxial compressive strength of the sandstone, limestone and marble are described, these rock specimens were heated under different temperature. The micro-structure changes of rocks under various temperature are observed with SEM, the fracture mechanism of heated rocks are studied, the developmental law of rock cracks are qualitatively and quantitatively analyzed. The study results showed that thermal stress affects uniaxial compressive strength of rocks, for example, with temperature increasing, the strength of the sandstone has an increase trend, but limestone and marble have a decrease trend. The temperature has a great influence upon deformation and destruction of these rocks too.

In this paper, the test results of mineral component and swelling behavior of the shale at An Zhou Coal Mine, D.P.R.Korea are introduced. The results showed that the shale has properties of high unit weight, low porosity and high content of hydrophilic clay mineral. With such properties, it will have large swell and high swelling force to the support of the project. Therefore it is considered that the effective measure to prevent unstable of the surrounding rock may be reducing disturbance and changes of water content. This paper is the first achievement in cooperation research between the colleagues of our institute and Institute of Rock Mechanics Academia Korea.

Many initial tailings dams are impervious in China, then, the seepage line is very high, and most sands are saturated in tailings pond. Under the action of dynamic force, the dynamic properties of tailings sands have vital importance for safety stability of tailings pond. Using electron-hydraulic dynamic triaxial apparatus, liquefaction tests are conducted, the dynamic properties of various sands in tailings pond are studied. Finally, the influence factors on liquefaction of saturated sands in tailings pond are discussed.

In this paper, crack propagation laws were studied by means of observing marble specimens, which were conducted uniaxial static and cyclic loading tests, with electron-microscope. The studying results showed: (1) Different parts of rock specimen suffer differential degree damage; (2) Failure models and characteristics of rock specimens change with loading paths; (3) Rock cracks are to be closed, when amplitude of cyclic stress is smaller than “fatigue threshold stress” of rock. This is mainly testimony of “rock fatigue threshold stress” existence.