6.1 Introduction This chapter will take up the design of several of the more complicated foundation members such as those required to support several columns in a line or from industrial loadings. When a footing supports a line of two or more columns, it is called a combined footing. A combined footing may have either rectangular or trapezoidal shape or be a series of pads connected by narrow rigid beams called a strap footing. The types of combined footing-Fig.6.1 Both the conventional "rigid"and the beam-on-the- foundation method of combined footing analysis will be presented.6.1 Introduction ▪ This chapter will take up the design of several of the more complicated foundation members such as those required to support several columns in a line or from industrial loadings. ▪ When a footing supports a line of two or more columns, it is called a combined footing. ▪ A combined footing may have either rectangular or trapezoidal shape or be a series of pads connected by narrow rigid beams called a strap footing. ▪ The types of combined footing-Fig. 6.1 ▪ Both the conventional “rigid” and the beam-on-the￾foundation method of combined footing analysis will be presented