Except for when a single pile or pier is used, a pile cap usually supports the vertical and horizontal
structural loads and transfers these loads to the piles. The pile cap is often of reinforced concrete,
the pile ends are embedded within the cap, and the cap is cast directly on the ground. It is
assumed that each pile in the group carries the same load for the situation where the piles are all vertical
and symmetrical, with the vertical load located at the center of gravity of the pile cap. This will
not be the case if the pile cap is subjected to a moment or an eccentric load. These cases will be discussed
in Sec. 6.3.4