1994 Fiscal Year Final Research Report Summary

Effects of inertia force on the dynamic behavior of Sand

Research Project

Project/Area Number	05452239
Research Category	Grant-in-Aid for General Scientific Research (B)
Allocation Type	Single-year Grants
Research Field	Geotechnical engineering
Research Institution	UNIVERSITY OF TOKYO
Principal Investigator	TOWHATA Ikuo UNIV.of TOKYO,Civil Eng.Professor, 工学部, 教授 (20155500)
Co-Investigator(Kenkyū-buntansha)	YOSHIMINE Mitsutoshi UNIV.of TOKYO,Civil Eng.Assistant, 工学部, 助手 (80251338)
Project Period (FY)	1993 – 1994
Keywords	Sand / Shear Strength / wodel test / Subgrade reaction / Shaking table
Research Abstract	A buried pipe was pulled laterally in a dry sand deposit in order to study the effects of shaking on the subgrade reaction force. It was found that the subgrade reaction decreases when and only when the ground was shaken laterally. The extent of this force reduction was strongly dependent on the intensity of shaking, whilst minor effects of embedment, sand density, and frequency were detected. Further studies were made by using water-saturated ground in which soil liquefaction occurred during shaking. It was found that dilatancy around the moving pipe increased the subgrade reaction. However, the mechanism of dilatancy was destroyed when shaking was still on-going. The cause of the observation stated above seems to be the loss of grain contact due to the cyclic stress application.

(6 results)