Study Of Rural Building Foundation Disaster Reduction On Seismic Loading

In2008,5.12Wenchuan earthquake, the southern Shaanxi region suffered seriousdamage, a large number of buildings damaged and collapsed, which brought a hugelosses to the people’s life and property. Combined with the villages construction and theexisting economic condition in the earthquake disasters, seeking a suitable ruralbuilding isolation has important economic and social significance.Sand cushion disaster reduction by friction-sliding through setting a certainthickness and density of sand cushion between the foundation and base of the building,when the building under earthquake effect, it can reduce the seismic energy, weakdynamic response of the upper structure and protect the safety of the building throughthe deformation of cushion layer and the relative sliding between cushion and basementconsume earthquake energy.This paper first through the research of the village and town architectural form, andthe damage form in the earthquake disaster area in the south of Shaanxi province, putforward some matters needing attention and reasonable suggestions for the post-disasterreconstruction, and recommend south Shaanxi rural building use the sand cushion fordisaster reduction by friction-sliding technology. Through the sand cushion theoryanalysis, found that the friction-slip properties of the contact surface of sand cushionand foundation is one of the key factors. Using the self-reshaping large-scale Single—Shear—apparatus, study on five different sand which the maximum size is2mm.Through the simple shear test, determine the friction-slip properties of the contactsurface of the five kinds of material, and analyzes the contact surface deformationcharacteristics. The finding, in the same in maximum diameter, a certain size has smallfriction coefficient than the gradation of continuous sand, and bigger sliding distance.The sand with uniform particle and lager size has better performance. Finally, combinedwith nonlinear numerical method, the hyperbolic elastic-plastic constitutive model andthe coulomb’s sliding model, programming the sand cushion friction-sliding structural dynamic schedule program by Matlab software, with the test from the friction-slidingcoefficient of normal structure， a single particle size sand cushion isolation structureand continuous gradation sand cushion isolated structure are analyzed, found that acertain size of sand cushion isolated structure are best shock absorption effect, this isconsistent with the test result. Therefore, recommended to use a certain size of sand inthe sand cushion as the materials of cushion isolation.