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From many research it is proved that liquefaction potential of sand is function of mainly relative density and confining pressure. During routine site investigations, high-quality sampling and laboratory testing of sands are not feasible because of inevitable sample disturbance effects and budgetary constraints. On the other hand quality control of sand fill can be done by determining in situ density of sand in layer by layer which is expensive and time consuming. In this paper TRL DCP (Transportation Research Laboratory Dynamic Cone Penetration) and DPL (Dynamic Probing Light) are calibrated to predict the relative density of sand deposit. For this purpose sand of known relative density is prepared in a calibration chamber which is a mild steel cylinder with diameter 0.5 m and height 1.0 m. Relative density of sand is varied by controlling height of fall and diameter of hole of sand discharge bowl. After filling, every time DPL and DCP tests are performed and for every blow the penetration of cone is recorded. N10 is then calculated from penetration records. Thus a database is compiled where N10 and relative densities are known. A correlation is made between N10 and relative density for two types of sand. A good correlation of N10 and relative density is found. [ABSTRACT FROM AUTHOR]

Physical modeling of liquefaction in 1-g shaking table and dynamic centrifuge test become very popular to simulate the ground behavior during earthquake motion. 1-g shaking table tests require scaled down model ground which can be prepared in three methods; water sedimentation, moist tamping and dry deposition method. Moist tamping and dry deposition method need saturation of model ground which is expensive and very difficult to achieve. Some model tests were performed in 1-g shaking table to see the influence of preparation method of model ground. Wet tamping and water sedimentation method of ground preparation were compared in these tests. Behavior of level ground and slope were also examined. Slope and level ground model test increased the understanding of excess pore pressure generation in both cases. Wet tamping method has a possibility of not being fully saturated. Pore pressure transducers should be fixed vertically so that it can not settle down during shaking but can move with ground. There was insignificant difference in acceleration and excess pore pressure responses between wet tamping and water sedimentation method in case of level ground. Spiky accelerations were prominent in slope prepared by water sedimentation method. Spiky accelerations were the result of lateral displacement induced dilatancy of soil. [ABSTRACT FROM AUTHOR]

A Pushrod is acting as a slender beam under axial loading and has a variety of applications, like in the automobile industry. For study purposes, a pushrod has been considered which is made of a superelastic shape memory alloy of a circular cross-section. The behavior of the pushrod is scrutinized during the applied force of vibration acting uniformly and eccentrically upon it. These dynamic loadings render a significant impact on its elastic behavior and a constructive formula for the deflection of the beam from its neutral axis is introduced. With this equation, the elastic curve deviations from its initial position are analyzed and its response to the increase in the number of modes is evaluated. The deflection of the beam is highest when the mode number is 1 and with the raise of modal shapes, the deflection tends to get decreased. A comparison with the static beam under affiliated force depicts that the deflection escalates in the beam under dynamic loading. With the change of force functions, different deflection curves have been calculated and from their comparison, the characteristics of this slender pushrod have divulged its other features too. For engineering structure study and design, vibration analysis has been marked as a must-to-do list. [ABSTRACT FROM AUTHOR]

A numerical investigation is performed in the turbulent combined-convection boundary layer with aiding flows in air along a heated vertical flat plate at a higher freestream velocity (Reδ0 = 600) by time-developing direct numerical simulation (DNS). At higher freestream velocity, the transition from laminar to turbulent delays for aiding flows and relatively a lower and higher heat transfer rates are observed, respectively, in the laminar and turbulent region compared to that of lower freestream velocity. The wall shear stresses are higher in the laminar region compared to that in the turbulent region, and at higher freestream velocity, the wall shear stress in the transition region shows a higher peak value. The intensity of velocity and temperature fluctuations for aiding flows with higher freestream velocity become appreciably lower than that for lower freestream velocity due to the laminarization of the boundary layer. [ABSTRACT FROM AUTHOR]