This methodology overcomes the restriction of height and combines the length of piles flexibly. Gravel piling can be completed without pricey equipment so as to save the cost. This invention is to drive steel pipe into designed level and then weld another steel casing pipe to achieve the goal of extension. It is more convenient and cost-saving comparing to traditional way. Other advantages of this methodology are low failure rate, high efficiency, easy to control construction quality, no limitation in pile diameter, pile number and pile length. Additionally, construction equipment is accessible, quick in assembling and easy to maintain.