BEHAVIOUR OF SOIL-CEMENT BEAM SPECIMENS UNDER REPEATED LOADS

Abstract

Vationolioation of design concepts for soi ' convent base eourfo is a problem engaging the attention of Hiçhviay Engineers, and repeated loading tests airy oxpoctcd to provide a real is meant of ossossing coil-ce rent properties in the laborotory for predicting Its field behaviour under repettve traffic loads. An attempt has been made here to study the effects of static and repeated stress applications on the strength and d oformat ion cbroctoristico of so it-co nt bci spec imons under !imply supported and two subgrodo support conditions., kl€aural strength being the main characteristic of semi-rigid aLabo, the strength of boom specimens worn determined for three care nt contents and for the different subgrade support Conditions► ' ho observed and calculated va1uo of defloetions for beam rooting over .i.as tc foundation Qre found to be approximately aquae. Repeated load studios Wore carried Out on bean spec tmons 'using three stress prcentages viz. 509 G, and 80)'. of uittmate strength of beam specimons in fin e. The resilient modulus of elasticity was found to ho indepondent of stress repetitions. Roth the elastic and resilient moduli decrease with the magnitude of the Opelied repeatedstress. Values of critical radius of curvature at which the bea w fats under static Ioade,were determined. Equatfons have been developed which define the fatigue behaviour of the beam specimens. It was further observed that the beam specimens subjected to 40 percent stress level for about 30 hours of repeated stress applications did not exhibit any distress condition, 0