I have gone through some pile cap design reference books and found those books only deal with the pile cap subject to vertical load. Does anybody know why not horizontal load is not considered?
The following references cover pile cap design thoroughly:
"Handbook of concrete engineering" Edited by Fintel, 1974
"Foundation Engineering:Theory and Practice" by Goodman & Karol, 1968
Canadian Foundation Enginnering Manual" 2nd ed. and
"CRSI Handbook" 2002
You just have to gather many references and then make up your own sheets for future reference.