A COMPUTER PACKAGE ON PROPORTIONING OF SHALLOW FOUNDATIONS

Abstract

Foundations are proportioned by a procedure of trials. A computer program facilitates an easy and efficient solution of the problem of proportioning a foundation. The present work is an effort, in this direction. Proportioning involves estimation of bearing capacity and settlement of footings. These depends on number of parameters like soil type, it's stiffness and compressibility properties, position of water table, shape and size of foundation etc. Further a number of procedures are outlined in literature to estimate bearing capacity and settlement. A computer package has been developed, accounting for all the above factors and other situations which usually occur in a real situation. The package developed is user friendly and a graphiCs user interface is developed for easy input. the facility of data modification has been incorporated to enable improvements in design. The software processes the data usually obtained from field tests such as standard penetration test and static cone penetration test in case of footing on sand and laboratory test data such as consolidation and shear test in case of footing on clay. The package is used to solve a few numerical problems and the results are presented to illustrate some of the features of the program. Assuming some typical data, results are obtained for settlement estimation by various methods such as proposed by Burland and Burbidge (1985) Schmertmann (1970) and De-Beer and Marten's (1957) and a comparative study is made. It is observed that settlement by Burland and Burbidge method under estimates settlement up to certain width when compared with the settlement calculated by Peck et.al method. IS code provision usually provide an overestimate of settlement in case of loose and medium dense sands.