Technique Research On Pit-jacked Piles Rising To Replace About Multistorey And High-rise Buildings In Loess Soil

Pit-jacked pile is a new technique as building reinforces and it has some special advantages. This technique is widely used by many years' popularization. Now pit-jacked pile can be applied in some other projects such as correction, ground strengthening and temporary shoring. The reinforcing technique to rise to replace is a kind of good way for treatment building slant angle and recovering building originally true height, and it is less applied for high building correction to replace in loess soil.This paper introduces the technique about pit-jacked pile and building correction to replace by rising. As a new technique, few people are familiar with it. This paper will research the technique of pit-jacked pile and building correction to replace by rising, including its developmental history, technique characteristics, advantages, construction process, applied scope, present condition and existent problems in sphere. This paper on the technique in application in the engineering will make complete analysis, compare construction technique and construction structure technique by technique economy, analyze and appraise construction scheme, explain the problem appearing in engineering, study its engineering application value.This paper will expatiate the interaction theory in pile and soil, make elastic-plastic analysis for soil around pit-jacked pile. The process of penetration is regarded as expansion of cylindrical cavity in infinite soil mass. Combining with the knowledge of elastic mechanics and plastic mechanics, we may make analysis for soil around pile. And we may deduce the cylindrical cavity pressure, radius of plastic zone, radical displacement in elastic zone, and excess pore water pressure in soil around pile and spherical cavity pressure at the end of pile.In calculation analysis, computation procedure will be used to calculate the single pile extreme limit bearing power. Comparison analysis will be made on the single pile extreme limit bearing power between which tests get and which formulas compute, and analysis will be made on their differences and the cause of them.This thesis will play a very big leading role and have engineering practical value on pit-jacked pile rising to replace in the northwest loess. But at the same time, much work will need to perfect it, in order to draw much large lessons from the work to guide the practical engineering.