Steel Pipe Pile Foundation Strengthening Works In The Research And Application

Steel-pipe pile foundation, as one of the most common foundation forms in high-rise, has developed very quickly at home and abroad in recent 20 years. New design theory has been developing, and new structural forms and new construction techniques have been appearing, they have been put into practice in project more frequently. Well-designed and constructed pile foundations can meet the demands of beating and deforming of high-rise building, and the effect turned to be satisfied, conversely pile foundations under bad influence of some abnormal factors are inclined to causing accidents as other construction machine structures. Quality accident of pile foundation is very common at home and abroad, With different way of understanding , different levels of facts mastering, and different treatment towards the accident, the consequence would also be different . Serious quality accident and improper treatment will do great harm to lives and properties. Scientific and reasonable treatment can make up for the loss of quality to most extent, as well as lower the influence from the accident.First, analyzed and studied the pile - soil and raft structure elementary theory, which analyzes and introduces function characters of single pile under vertical load, including general rule and the characteristic of the single pile load transmission, the single pile vertical rigidity, the pile destruction pattern, the single pile supporting capacity depth effect, negative friction influence and the rule of the soft soil the friction pile supporting capacity which grows along with the time; in the pile under horizontal load function character, including crosswise load function under pile power transmission characteristic and destruction character, pile under crosswise function differential equation and computational method.Second, systematically elaborated the steel-pipe pile construction and the craft and the construction quality specification, and has studied the common displacement oversized, the pile reverse as well as the pile damage breaks off of the steel-pipe pile in the construction and the corresponding countermeasure which was adopt.Finally, in view of two project examples, the theory is applied to practice, it was shown that steel pipe pile was feasible and valuable in foundation reinforcement engineering.