Experimental Study On Anti-earthquake Effect And Seismic Clogging Mechanism Of Pervious Concrete Pile

In recent years, a large number of buildings got damaged because the earthquakes had taken place frequently, which not only related to seismic performance of the buildings, but also had a great relationship with foundation seismic processing technique. In the current methods of foundation treatment, composite foundation technology is developing rapidly, which has been widely applied. The vertical reinforcement in composite foundation can generally be granular materials (such as sand pile, gravel pile), semi-rigid pile (such as cement soil mixing pile) and rigid pile (such as plain concrete pile, CFG pile) generally. Granular pile is permeably well, but low strength, so it is easy to destroy. The gravel pile composite foundation has small bearing capacity and big post-construction settlement; Rigid and semi-rigid piles are of high strength, but low permeability. They affect the consolidation of the foundation, and can t eliminate the liquefaction of the foundation caused by the earthquake. Pervious concrete is a new kind of building materials, and its strength and rigidity are considerable while it has good water permeability. Pervious concrete was mainly used for other projects such as pavement engineering at one time, and there was no engineering precedent which relied on it for foundation anti-earthquake processing. In this paper, it is intended to be used in the seismic resistance of composite foundation, and it will replace other piles. But as a new type of composite foundation, its anti-earthquake performance research stays at the theoretical level only. This paper will be combined with the engineering survey to explore its pressure-reduction effect and anti-earthquake mechanism of the pervious concrete piles composite foundation.In this paper, through field test and laboratory test, the pressure-reduction effect and clogging mechanism about pervious concrete piles under the action of earthquake were investigated, the contents were as follows:Firstly, relying on practical engineering, the research that construction technology of pervious concrete pile and the effect of foundation treatment were carried out. The pervious concrete mix of laboratory was improved to make it more suitable for industrialization; Vibrating tube-sinking method was used for pervious concrete pile construction, and improved pervious concrete pile composite foundation construction technology. The small strain, pumping core detection and single pile bearing force of the pervious concrete piles were carried on, and made the test of bearing capacity of composite foundation at the same time. By observing the finished result of the pile and the bearing capacity of foundation, explored the practical engineering performance of the pervious concrete pile.Secondly, the pressure-reduction effect of pervious concrete pile composite foundation under the action of earthquake was explored in the actual project. At the scene simulating earthquake action by using dynamic compaction, to detect the pore water pressure changes and dynamic response of cement soil mixing pile composite foundation, pervious concrete pile composite foundation and gravel pile composite foundation after the earthquake, and recorded the consolidation drainage capacity of the above three types of composite foundation during the embankment construction process. Through the comparative analysis, the advantages and disadvantages of pervious concrete pile composite foundation were analyzed.Finally, the clogging condition of the pervious concrete pile was studied by laboratory model test of composite foundation after earthquake action. Through the observation of pervious concrete pile clogging phenomenon with six kinds of variables (twenty-four test conditions), such as pile porosity, pile spacing, earthquake peak acceleration, vibration time, vibration frequency and impervious layer thickness, explored earthquake resistant effect and clogging rule of the pervious concrete pile.This article carried out a large number of experiments to explore the clogging rule of pervious concrete pile under the action of earthquake, and actually measured pressure-reduction effect and consolidation property of the composite foundation in the field of engineering, combining with both researched anti-earthquake performance of the pervious concrete pile composite foundation. This has laid the foundation for the engineering application of pervious concrete pile, and has great guiding significance to the anti-earthquake technology of foundation.