This document discusses the design of pile caps, which connect piles to the superstructure. It provides an example of designing a pile cap to support two piles and a column. Key steps include: 1) Calculating pile cap dimensions based on loads and pile arrangement. 2) Using the truss analogy to design tension reinforcement. 3) Checking punching and vertical line shear stresses. 4) Calculating distribution steel based on code requirements. The example calculates reinforcement for a pile cap supporting two 600mm diameter piles under 3000kN load. It checks capacity against punching and vertical line shear stresses.