The densities and seismic velocities of rocks are relatively weak functions of temperature, pressure and composition unless these are accompanied by a drastic change in mineralogy. The physical properties of a rock depend on the proportions and compositions of the various phases or minerals-the mineralogy. These, in turn, depend on temperature, pressure and composition. In general, one cannot a...

tunnelling through cities underlain by soft soil, commonly associated with soil movement around the tunnels and subsequent surface settlement. the predication of ground movement during the tunnelling and optimum support pressure could be based on analytical, empirical or the numerical methods. the commonly used earth pressure balance (epb) tunneling machines, uses the excavated soil in a pressu...

abstract the prediction of active earth pressures is essential to the design of retaining walls in case of reinforced and unreinforced soils. in this study, a new analytical method is presented to determine the coefficient of earth pressure. the horizontal slice method is used to compute the active earth pressure behind a rigid retaining wall in consideration of the granular soils. to verify th...

according to the irrigation systems design standards, allowed pressure variation in lateral pipes is 20 percent. reasons for this rate selection, which since the 60's is performed, are not known. the increased changes in allowed pressure tubes to lateral pipes design, the increased sprinkling system required pressure and the increased nonuniform sprinkler distribution, so energy supply cos...