جستجوی مقالات مرتبط با کلیدواژه « ضریب لرزه ای » در نشریات گروه « عمران »

Although Earthquake prediction studies are being widely considered their findings are uncertain and criticized regarding problem complexity and scientific content. Therefore; based on the robust analysis, the detailed investigation can be of great value. The recent triggered events in Iran reveal that this country is under pressure and contemporary tectonic stress pattern of the region changes. This motivates researchers to explore its different aspects. In this research, statistical analysis is made on the records listed in International Institution of Earthquake Engineering and Seismology (IIEES) catalog and b-value of the Gutenberg-Richter Relationship was computed. The time-dependent values of being can act as a stress accumulation indicator in a region. Therefore, Iran was subdivided into 29 zones and b-value was explored in every zone between the years 2010 and 2017. The results are in a proper agreement with the seismic regime of the regions wherein earthquakes occurred recently. Furthermore, an interesting hazard map was resulted in, introducing the regions with accumulating stresses therefore, being susceptible for experiencing future events.

The purpose of footing design is transferring structure load to soil without causing shear failure and extra settlement in soil. Therefore, footing bearing capacity should be considered in various projects. In special case, footings are placed in various positions with respect to slope ground and position of ground slope affects footing bearing capacity. In fact, slope affects failure surface of soil beneath the foundation remarkably and therefore, footing location with respect to slope must be cared to determine exact footing bearing capacity. In present paper, analytical method is presented based on soil stability beneath the footing. Virtual retaining wall method is used in present study and by applying equilibrium between active and passive forces on virtual wall, footing bearing capacity on reinforced and unreinforced soils is determined in various positions with respect to slope ground. Also, varied parameters include soil resistance, footing spacing with respect to slope ground, width and depth of foundation and seismic coefficient. Results indicate, in various depths and widths of foundation, bearing capacity of footing on flat ground is more than top of slope and bearing capacity of footing top of slope is more than down of slope. Also, bearing capacity of footing on slope is minimum. Based on proposed method, footing location with respect to slope affects passive and active force on virtual retaining wall and footing bearing capacity remarkably. Also, the proposed method can determine effect of slope angle and reinforcement on footing bearing capacity. Presented method indicates effective distance from slope crest is almost 4.5B. Finally, the predicted results are compared with those reported from analytical and experimental methods performed by others, indicating an acceptable agreement.