Seismic-resistance Analysis Of Large Box Type Multi-troughs

Water shortages have a big impact on economic development in our country, even bring difficult to people's life in many places. So our country implemented the project of divert water from the south to the north, The aqueduct is an important kind of conveyance water buildings, only in the midcult project reaching to 47 seats.The different between aqueduct and other hydraulic engineering is that, when running the top slot body has a large bulky and quality within the flow of water, if they meet earthquake, the fluid-solid coupling effect coming from big quality water and slot wall occurring is not safe to the aqueduct.As is known to all, China is a more earthquake country, according to records, almost all the provinces happened destructive effect earthquake. in the devastating earthquake. During the 7 magnitude earthquake world happened in 20 century, China account for 35%, there are three times reaching to 8.5magnitude.According to statistics, in the 10 global death toll more than 10 thousand, the total more than million, among which 4 times occurred in our country the death account for 55%. Therefore, our country is one of the world's most serious earthquake disasters. From the three lines of divert water from the south to the north project to see, most lines across the quake zones. According to the ground motion parameter zoning map promulgated in 2001 August, by the basic intensity 50 years exceedance probability 10% the divert water from the south to the north project is located inâ…¦degrees above area (peak acceleration is 0.1g, g is gravity acceleration), eastern line take up 67% midline 59%, west 91%.;located in high earthquake intensity area (peak acceleration is 0.2 g),eastern line take up 6%, mid-line 8%, west line 23%. Therefore ,the anti-seismic problems is very prominent divert water from the south to the north project, and among them, the aqueduct with huge quality concentrated at the top anti-seismic problems is prominent, so the large aqueduct structures anti-seismic analysis is very necessary. over recent yearsThe authors review a large number of books[1,2,4,5,10,11,12,13] about divert water from the south to the north project relevant aqueduct seismic, show that, in the divert water from the south to the north project, the aqueduct is used mostly open box structure, such as Cao river aqueduct,Ming river aqueduct and Qu Zhuan Gou aqueduct,etc. When earthquake, this type of aqueduct trench wall (namely aqueduct body side wall) the transversal stiffness are low, so is the weak positions. Seismic aqueduct, To find the causes, and also noticed that box structure in holistic superiority, the paper for just open type aqueduct seismic performance of comparative study, especially aqueduct box-like structure seismic dynamic analysis, including the structure modal analysis and the seismic response analysis. In the paper, With finite element analysis software ANSYS carry on the modeling and computing research on the aqueduct with box aqueduct structures, basin type rubber bearing and supporting slot mound. With the HOUSNER model to imitate Fluid-structure interaction problem; With spring-damping unit to imitate rubber bearing basin; Between adjacent cross section simulation, it is adjacent cross slots half body structure of quality to the quality unit form in finite element model of additional pier upper trough. Using Ninghe Tianjin seismic wave, exerted on finite element model of horizontal and vertical, calculates the structure 20 levels of natural frequencies and principal mode, structure the displacement response and stress response. As Ming river aqueduct for example, the two kinds of structure types:1) open four side wall three two-tank aqueduct body, rubber bearing basin, supporting aqueduct pier; 2) three holes box aqueduct body, rubber bearing basin, supporting aqueduct pier, separately carry on the modal analysis and the seismic response analysis. From the calculation results, can understand two types aqueduct body structure, each place earthquake displacement response and seismic stress response of the distribution regularity maximum displacement and maximum stress, the results show that the integrity of the aqueduct is improved and is good for anti-seismic.