A new method to direct calculate of base sizes of rectangle spread foundation for eccentric sub-column

The method of practical calculation on base sizes is given in the article.It is deduced from the designing methods of rectangle spread foundation of single eccentric of sub-column and the conditions of the minimal anti-force of the base P_kmin=0 and 3k≥0.85b.Comparing with the existing calculation,it can avoid repeatedly trial calculations and cubic equation and had economic,reasonable and simple advantages.