AN EXPERIMENTAL STUDY ON ADVANCEMENT OF DAMPINGPERFORMANCE OF FOUNDATIONS IN SOFT GROUND PART1FORCED VIBRATION TESTS OF A FOUNDATION BLOCKCONSTRUCTED ON IMPROVED SOIL MEDIUM

摘要

Purpose of this study is to enhance attenuation performance of structures that will be constructed in the softground area. We conducted material tests to obtain basic properties of the soil cement column. The forced vibrationtests then were carried out to acquire dynamic feature of the reinforced concrete block constructed on improvedsoil mediums. Additional forced vibration tests for various conditions of trenches dug along the block wereconducted to obtain fundamental features of damping effect of the side surfaces of the test block.According to results of the material testing, densities of the soil cement columns were 1.45-1.52 g/cm cm3 and theunconfined compressive strengths were 2.4-4.2 times as large as the specified design strength (1 Mpa). Incomparison of resonance curves by experiments and simulation analysis, simulation analysis results estimated bythe hybrid approach were in good agreement with experiment ones for both the X and Y-directions. From theresults of the forced vibration test focusing on various condition of the trenches dug along the test block, it wasindicated that response of tamping by the rammer decreased compared with that of treading.