[1] Gravity acting on topography creates differential stress, which, for sufficiently high, steep topography, can fracture intact bedrock. If static fatigue governed the time dependence of that fracturing, a feedback should exist between incision of the landscape and fracturing. The timescale for static fatigue decreases exponentially with differential stress. By creating deeper, steeper valley...

The purpose of this study is developing of a model for estimation of elastic modulus of intact rocks. Mechanical rock excavation projects require static modulus of elasticity (E) of the intact rock material. High-quality core specimens of proper geometry are nedded for the direct determination of this parameter. However, it is not always possible to obtain suitable specimens from highly fractur...

Laboratory tests were performed on 54 large size specimens of jointed rock mass under uniaxial loading conditions. Based on this experimental study, a methodology has been suggested to estimate strength and tangent modulus of rock masses through a weakness coefficient. The methodology involves mapping of joints in the field and laboratory testing of intact rock specimens to arrive at rock mass ...

Point load testing is used to determine rock strength indexes in geotechnical practice. The point load test apparatus and procedure enables economical testing of core or lump rock samples in either a field or laboratory setting. In order to estimate uniaxial compressive strength, index-to-strength conversion factors are used. These factors have been proposed by various researchers and are depen...

uniaxial compressive strength (ucs) is one of the most significant factors on the stability of underground excavation projects. most of the time, this factor can be obtained by exploratory boreholes evaluation. due to the large distance between exploratory boreholes in the majority of geotechnical projects, the application of geostatistical methods has increased as an estimator of rock mass pro...

Underground rock masses have shown a general trend of natural balance over billions of years of ground movement. Nonetheless, man-made underground constructions disturb this balance and cause rock stability failure. Fractured rock masses are frequently encountered in underground constructions, and this study aims to restore the strength of rock masses that have experienced considerable fracturi...

one of the most important parameters used for determining the performance of tunnel boring machines (tbms) is their penetration rate. the parameters affecting the penetration rate can be divided in two categories. the first category is the controllable parameters such as the tbm technical characteristics, and type and geometry of the tunnel, and the second one is the uncontrollable parameters s...

RMR, Rock Mass Rating, is one of the famous rock classifications. However, RMR was proposed empirically and absolutely depends on the experience of engineer. Therefore, engineering verification is needed for RMR system itself. In this study, the factor analysis and the multiple regressions were performed in order to evaluate the validity of rating factor of RMR. Also numerical analysis was carr...

Since rock fracture is a key property for different rock engineering applications, rock fracture measurement is often carried out in classifying the rock mass. Most geo-mechanics models (e.g. finite element) are of the equivalent continuum type in which fractures are represented not individually, but by their influence on a large element of the rock mass. Elastic modulus, for example, is obtain...