COMPUTER AIDED EVALUATION OF SETTLEMENT AND ,STABILITY OF OIL STORAGE TANK FOUNDATIONS

Abstract

ABSTRACT Cylindrical storage tanks which form a familiar part of petroleum refineries and chemical plants, hold large volumes of valuable and hazardous products. In view of serious consequences of failure of such tanks, it is necessary to examine the stability of oil tank foundations and estimate the magnitude of total and differential settlements even under comparatively favourable soil conditions. One of the major problems associated with oil tanks is that they are often founded on weak soils as generally the refineries are located in coastal areas. This problem is further aggravated when the properties of soil within the influence zone vary radially and vertically. In such a case it is very important to estimate the settlement and examine the stability accurately but there is limitation as the theories available are suitable for homogeneous soil conditions. So there is a need to mould the available theories to handle difficult soil conditions usually met wilt. The present work is an effort in this direction. The work reported includes a detailed discussion on (a) structural features of oil tanks, foundation systems and ground improvement techniques commonly adopted, performance criteria for oil tank foundations, case histories, methods of settlement estimation and stability analysis and (b) development of computer software OILTANK in C language and study the effect of certain parameters on settlement and stability of oil tank foundations.