The floor bearing strength of rock strata is markedly influenced by both the presence of layers and joints with respect to their location, strength and orientation. The paper depicted the research works carried out for the case of surface footing using physical modeling technique. In order to determine the floor bearing strength, plate loading test on simulated floor strata are carried out for varying geotechnical conditions of weak floor strata. The entire tests for floor bearing strength were conducted under condinement in the self developed testing blocks resembling the in-situ condition. The load exerted by the plate on the floor strata was assumed to be uniformly distributed. The analysis were carried out by considering the various parameters like orientation of joints and layers with respect to the direction of loading, variation in the jo nt sets i.e. joint spacing and the layer thickness as a function of footing plate width. The result indicates that bearing strength is significantly related to the location and orientation of joints and the layers. Bearing strength of jointed rock mass is almost 0.6 times the bearing strength of intact rock mass for joint located vertically i.e. in the direction of applied load. The ratio reduced to almost 0.3 for joint located at an angle of 80° with the direc ion of loading. With the increase in the weak sandwiched layer thickness, there is a considerable decrease in bearing strength. Further the bearing strength in the case of the joint located at the center of the footing is always higher than the joint located at the edge of footing.
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