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The article offers information on of use of large shearbox, a rapid test used for measurement of the shear strength of soils. It presents information on drained strength and residual strength shearbox tests. It mentions that material is compacted into shearbox already in place in the machine, if possible, to avoid the difficulties of subsequent handling.

The article offers information on of use of small shearbox, a rapid test used for measurement of the shear strength of soils. It mentions that a low density may be obtained by pouring the sand very rapidly into the shearbox from a small height. It presents details of lever arm for applying high normal pressures to shearbox specimen.

The article offers information regarding use of consolidation tests on peat in oedometer consolidation test for the determination of the consolidation characteristics of soils of low permeability. It mentions that peats have a very high compressibility, low shear strength, high initial permeability, very rapid initial rate of consolidation and a high degree of secondary compression.

The article offers information regarding use of unconfined compression tests in the measurement of the undrained shear strength of soils. It mentions steps involved in the test procedure like preparation of apparatus; need for weighing the specimen on the tray, place in the oven, weigh when dry and cool and calculate the moisture content, as in the standard moisture content test; and need for determining remoulded strength of a saturated clay, which is used for calculating sensitivity.

The article offers information on of use of fall cone test for measurement of the shear strength of soil. It mentions that the fall cone test utilizes the apparatus for the determination of the liquid limit by cone penetrometer, but the geometry and mass of the cone used vary according to the anticipated shear strength.

The article offers information on measurement of the shear strength of soils in the laboratory by two direct methods, both of which involve the sliding of one portion of soil on another. It mentions that stress control method has certain advantages in some long-term tests in which increments of stress must be applied slowly, and in tests for the study of the effect of creep under constant shear stress.

The article offers information on laboratory tests which are used for the determination of the physical properties of soils like shear strength, permeability, and compressibility. It mentions information on use of the tests for determining physical properties of soils which are under the U.S. Standards given by the American Society for Testing and Materials (ASTM).

Due to the limitation of population density and availability of land, a large portion of the landfills of Taiwan, China are located in mountainous area. Current regulations do not require slope stability analysis for these landfills. As a result, almost all of the landfills were not designed to maintain a suitable factor of safety against failure. The composition of Taiwan&s solid waste differs considerably from that of the United States or any other country in the world. However, the lack of data of local solid waste poses a great limitation to engineers. The objectives of this research are to collect shear strength data from in-situ tests and perform a series of stability analyses. The results show that the cohesion and friction angle of the MSW at Chu-nan and Hu-kou landfills are 34.9 kPa and 37.9°, 33.6 kPa and 32.1°, respectively. In addition, the coefficients of subgrade reaction, kv, are 875.25 kN/m3 and 494.33 kN/m3, respectively. Results of 2-D and 3-D slope stability analyses show that the factor of safety increases with lower height of wastes, longer length of waste body, smaller slope angle of the back of the excavation, and steeper face slope of final cover. In addition, 3-D analysis indicates that the factor of safety decreases with the widening of the mouth of the landfills on slopes. [ABSTRACT FROM AUTHOR]

The strength properties of unsaturated soil are far more complicated than those of saturated soil. As a kind of typical and widely spread unsaturated soil, expansive clay shows a very close relationship between its shear strength and water content, for its high content of hydrophile, such as montmorillonite, illite and etc. The shear strength of soil is of much significance in the design of foundation and slope in expensive soil area. The determination of shear strength for expensive soil is always an important issue in this aspect. Based on the investigation of expansive clay in a slope along Han-Shi highway, Hubei Provence, some unsaturated shear tests with suction control have been conducted, and then, unsaturated mechanical parameters have been obtained using double-variables strength theory, and characteristics of the unsaturated shear strength of the specimen have been explored. Results indicate that slight shear dilatation appeared during the unsaturated shearing course and its value decreases with the increase of confining pressure and suction. For lower suction, the cohesion of the tested soil specimen linearly increases with suction increases. The shear coefficient for testing specimen is 10.7°. [ABSTRACT FROM AUTHOR]

The surface-active agent is common in the environment and its effect on the engineering properties of soil remains unclear up to date. The surface-active agent, Sodium DodecylBenzene Sulphonate was found able to cause obvious changes in mechanical behaviors of Chinese loess. The shear strength behavior decreased in the SDBS- polluted loess. The effect of the pollutants on the shear strength of loess is found to be similar to that of moistening, and the influence of pollutants gets more and more weak with increasing the degree of saturation. The microstructure was investigated to explain the experimental observations. It is proposed that the presence of SDBS in loess and other soils should be tested and the relevant influences should be evaluated in engineering practices in the future. [ABSTRACT FROM AUTHOR]

The article focuses on the engineering properties of loess. Topics discussed include factors that influence the behavioural properties of loess, particle shape, particle size, soil fabric, minerals presents in loess, natural moisture content, Atterberg limits, bulk density, permeability and infiltration, collapsibility, and shear strength.

The article discusses soil erodibility and plant cover. Topics discussed include factors that affect the erodibility of soil including the grading, stability of the aggregates and clods, shear strength, infiltration capacity and the organic/chemical content, an erodibility index, and effectiveness of plants in controlling erosion.