this paper studies thoroughly and deeply the results of about one hundred triaxial compression tests on thirty types of rockfill materials. the materials are categorized in accordance with their particles shape (angular / rounded) and gradation characteristics. the main tool of the study is the hyperbolic model developed by duncan and chang. the focus of the study is on the variations of deform...

Soil reinforcement can be considered as the combination of two parts. One part is soil for compressive stress capacity and another part is some material such as geosynthetics such as steel belts and fibers for tensile stress capacity. Soil improvement is one of the useful methods to increase the strength parameters of the soil. The main goal of this study is to evaluate the effects of GFRP on t...

An anchored sheet wall is commonly used in retaining deep excavations. Anchor force is one of the critical design parameters in practice. Based on the kinematical admissible failure mechanism, a limit analysis approach to determine the anchor force is presented. The explicit formula for the anchor force is given, which makes it easy to calculate using a simple calculation program such as MS Off...

The fine lunar surface material at the Surveyor 3 landing site has about 3 X 108-dyne/cm 2 cohesion, 35 ø angle of internal friction, 3 X 105-dyne/cm ' static bearing capacity. A small rock withstood a local pressure of 2 X 107 dynes/cm -ø. Soil strength and density increase significantly at depths of a few centimeters. Exposed surface has a considerably higher albedo than the material just bel...

Slope stability is one of the most important issues in open pit mining design. The main purpose of any open pit mine design is to propose an optimal excavation configuration, considering safety, ore recovery and financial return. An accurate pit slope design which accounts for the mine geology, structural geology, rock mass properties, and hydrogeology models of the mine area, drastically enhan...

In recent years, the nanoscale zero-valent iron (NZVI) particles have been used successfully for the degradation of hydrocarboncompounds and remediation of other pollutants. Nevertheless, as far as we know, there is no specific study on the improvement of thegeotechnical properties of contaminated soils with hydrocarbon compounds by NZVI. This study used NZVI particles to remove gasoil in a cla...

Particle size distribution of gravelly soil plays a crucial role in debris flow initiation. For better understanding the mechanism of debris flow formation, two crucial mechanical property parameters of the gravelly soil are required to be studied meticulously: hydraulic conductivity and strength. With the aim of measuring the composition of the gravelly soil, 182 soil samples were taken from d...

slope instability due to landslides is particularly common in iran. it is possible to fight against these hazards thanks to the roots of trees, which provide an important contribu-tion towards the stability of hillslopes. however, our knowledge of the effectiveness of roots for slope stability needs improvement. therefore this study was carried out on the effect of tree roots on slope stability...

In order to reduce the power consumption of screw conveyor and improve productivity, this study investigated such mechanical characteristics rubbed maize straw as coefficient sliding friction, angle repose, internal friction coefficient, cohesion, flow function value compressible with respect its moisture content density. An experiment was designed consists a characteristic test-bed, direct she...