Reasearch On The Bearing Capacity Of Bridge Pile In Expansive Soil

Expansive soil is a special wet bilge drying shrinkage properties of cohesive soil,due to special engineering properties of expansive soil makes the interaction betweenpile and expansive soil is much more complex than the average in the soil, whencalculating the bearing capacity of single pile and cope with its particularity intoconsideration, when calculating expansion of vertical bearing capacity of single pile asif directly using the highway bridge standard about foundation and foundation design(JTG D63-2007) and technical specification for the building pile foundation (JGJ94-2008) in the calculation method is given, it is concluded that the bearing capacityand the actual bearing capacity of pile foundation have a large gap, can not meet therequirements. Therefore, the expansive soil of pile side friction in the distribution ofresearch to determine the bearing capacity of bridge pile in expansive soil calculationparameters is of great significance.This paper takes hebei province transportation hall project of key research projectsas the backing, the geotechnical engineering at home and abroad of expansive soil inpile foundation research results for reference, through indoor physical and mechanicalproperties test, single pile static load test, axial force test and pile side frictioncalculation analysis, obtained the following results:(1) In the south-to-north water diversion project in the handan city of flyover of themain canal Guo He production of expansive soil near the bridge as the research object,in the national standard and the test on the basis of relevant research data, through alarge number of indoor test, analyzes the physical and mechanical properties ofexpansive soil and swell-shrink characteristics;(2) To the principle of stress of the bridge pile foundation and bearing propertiesare analyzed, and found the factors that influence the vertical ultimate bearing capacityof pile foundation, the calculation method of pile bearing capacity of Bridges of widelyused now were summarized;(3) Guo handan segment and bridge south side of south-to-north water transferproject on expansive soil foundation of three trial pile static load test, according to thechart to determine single pile limit bearing capacity and standard capacity, axial force of piles was studied, and the size of the pile side friction and the distribution along the pileshaft;(4) Through the analysis of the physical and mechanical indexes of pile lateral soilsamples in the depth of the pile body within the scope of the change rule, found with theinternal relation between the change law of pile side friction, determines the influencefactors of pile side friction;(5) By means of the calculation of different parameters on the standard value ofbearing capacity of single pile, the reasonable calculation parameters of the single pilebearing capacity.