CUURENTLY I AM HANDLING A PROJECT WHERE 200X200 RC PRECAST PILES HAS BEEN CHOSEN. IT'S PREDICTED THAT THE FOUNDING DEPTH OF HARD LAYER IS AT ABOUT 45M. THEREFORE 200X200 PILE WITH 7 JOINTS IS TO BE USED SINCE THE SMALL PILE SIZE COMES ONLY WITH 6M LENGTH.
MY CONCERN IS 7 JOINTS IS A PILE SEEMS TOO MANY AND CAN ANYBODY LET ME KNOW HOW TO FIGURE OUT THE MAXIMUM ALLOWABLE NUMBER OF JOINT IN A PILE.
Klang region in that type of soil. I remember some areas of Klang you must pile very deep to get to the hard strata, guess you got it.
I got the 5-7% reduction from many consultant mates of mine (they practice 5% I practice 7% for prudence). One said it is from the BS but I'm not too sure. I will find out further since I guess I need to know myself.
230x230 pile. Due to the SI system of measurement, most call it the 225x225 pile. Good idea since it is bigger in size and therefore slenderness is less important an issue but there is a problem. If your project is located in the central region of Malaysia, the existance of 225x225 or 230x230 moulds for casting this pile is quite few and manufacturers do not keep much of this uncommon size for stock. If your project is relatively small and is not too soon to provide a good lead time for casting, this is not a problem.
In Klang the bracing effect of the topsoil is not very good. In fact, the soil is very soft until it reaches the hard soil. Because of this the soil cannot provide good bracing to the pile. Meaning your pile size still too small mate. I advice you to seek information from other consultants familiar with klang region piling and pool information resource.
Perhaps you can redesign your required pile to maybe a larger pile with less steel (longitudinal and links)since it is not hard driving. I advice you to contact various RC pile manufacturers in the central region of Malaysia like PKM, Hume and Sejati (most others are plain shoddy) since they have experianced engineers who can advice you for free as well as having the required moulds in a decent quantity.