【摘要】：鋼筋混凝土框架結構因其空間布置靈活,自重輕,整體性好,便于工業(yè)化施工等優(yōu)點,在我國廣泛應用于學校、醫(yī)院、住宅、辦公樓等人員密集建筑。目前我國結構設計中,規(guī)范要求將框架結構填充墻視為非結構構件,建議采用輕質材料,在結構整體受力分析時,不考慮填充墻對其周邊框架的影響,僅在計算框架結構自振周期時乘以0.6~0.7的折減系數(shù)[4]。近些年我國西南地區(qū)幾次較大地震中,框架結構因沒有合理考慮填充墻而造成結構破壞的案例非常多,由此也造成了較大的人員傷亡和經濟損失。因此,框架結構填充墻對結構主體作用的考慮,在規(guī)范現(xiàn)有要求的基礎上有待進一步完善。另外,研究表明斷層附近是地震作用下破壞最為嚴重區(qū)域,受斷層破裂方向性效應影響,在破裂傳播前方地震動速度和位移時程呈現(xiàn)出高強度脈沖,其為引起近斷層結構破壞的一個主要原因[28]。目前大部分學者關于速度脈沖地震動的研究主要集中于分析脈沖周期和峰值與震源參數(shù)間的關系以及其對不同類型結構的破壞機理[12][13],然而近斷層區(qū)域結構抗震分析時速度脈沖地震動強度指標的選取有待進一步研究。目前我國抗震分析和結構設計中采用的地震動強度指標主要為地面峰值加速度PGA[10],但近年來幾次大震中結構震害表明近斷層區(qū)域速度脈沖地震動作用下PGA作為地震動強度指標不太完善。本文主要以蘆山中學框架結構教學樓為分析對象,結合該教學樓在2013年4月20日蘆山地震中實際震害特點,運用大型非線性有限元軟件ABAQUS對其進行數(shù)值模擬,主要探討采用不同密度和剛度填充墻材料的框架結構教學樓在不同強度地震動作用下,填充墻和框架結構主體的震害表現(xiàn)。分析表明,七度抗震設防框架結構教學樓,低烈度地震作用下,填充墻材料為多孔磚的框架結構各樓層位移相比填充墻材料為燒結普通磚的框架結構各樓層位移較大;高烈度地震作用下,填充墻材料為燒結普通磚的框架結構各樓層位移相比填充墻材料為多孔磚的框架結構各樓層位移較大。分析目的主要是指出目前我國結構設計中框架結構填充墻材料的選擇不太完善,當框架結構可能遭受地震作用較小時(0.2g及以下),建議采用密度和剛度較大的填充墻材料;當框架結構可能遭受地震作用較大時(0.2g以上),建議采用密度和剛度較小的填充墻材料。本文以蘆山中學框架結構教學樓為分析對象,對其進行多組速度脈沖地震動作用下彈性、塑性階段時程分析,主要探討多組不同強度速度脈沖地震動作用下框架結構最大地震響應與地震動強度指標間的線性相關性。分析表明,速度脈沖作用下,當框架結構受力處于彈性階段時,地震動強度指標PGV和PGA與結構最大地震響應相關性較好;當框架結構受力處于塑性階段時,地震動強度指標PGV和PGD與結構最大地震響應相關性較好。綜合考慮時,近斷層區(qū)域速度脈沖地震動強度指標PGV與框架結構最大地震響應線性相關性較好。分析目的主要是從有限元分析的角度表明目前我國近斷層區(qū)域抗震分析和結構設計中選用PGA作為地震動強度指標不是很完善,建議選取地面峰值速度PGV作為地震動強度指標。
[Abstract]:Reinforced concrete frame structure is widely used in schools, hospitals, residential buildings, office buildings and other crowded buildings in China because of its flexible spatial arrangement, light weight, good integrity and easy industrialization construction. In the analysis of the whole structure, the influence of infilled wall on the surrounding frame is ignored, and the reduction factor of 0.6-0.7 is only calculated when the natural vibration period of the frame structure is multiplied [4]. In addition, the study shows that the area near the fault is the most severely damaged area under earthquake action, and affected by the directional effect of fault rupture, the velocity and position of ground motion in front of the rupture propagation are affected by the directional effect of fault rupture. At present, most scholars'researches on velocity pulse ground motion mainly focus on analyzing the relationship between pulse period and peak value and source parameters, as well as the failure mechanism of different types of structures [12] [13]. However, near-fault regional junction The selection of velocity pulse ground motion intensity index in structural seismic analysis needs further study. At present, the ground peak acceleration PGA [10] is the main seismic intensity index used in seismic analysis and structural design in China, but in recent years, the damage of structures in several major earthquakes indicates that PGA acts as earthquake under the action of velocity pulse ground motion in near-fault region. The dynamic strength index is not perfect. In this paper, taking the teaching building of Lushan Middle School as the analysis object, combining with the actual damage characteristics of the teaching building in the Lushan earthquake on April 20, 2013, the large-scale nonlinear finite element software ABAQUS is used to simulate the dynamic strength of the building, mainly discussing the frame structure with different density and stiffness filling wall materials. The analysis shows that the displacement of each floor of the frame structure with porous brick as filling wall is larger than that of the frame structure with sintered common brick as filling wall under low intensity earthquake. The main purpose of the analysis is to point out that the selection of filling wall materials for frame structures in China is not perfect at present, and the frame structures may be subjected to earthquakes. When the density and stiffness of the frame structure are small (0.2g or less), it is suggested to adopt filling wall materials with large density and stiffness; when the frame structure is likely to be subjected to large earthquake action (above 0.2g), it is suggested to adopt filling wall materials with small density and stiffness. The time history analysis of elastic and plastic stages mainly discusses the linear correlation between the maximum seismic response and the seismic intensity index of frame structures under pulsed ground motions of different intensity velocities. The correlation between PGV and PGD and the maximum seismic response is good when the frame structure is in plastic stage. The angle shows that PGA is not a perfect seismic strength index in seismic analysis and structural design of near-fault areas in China. It is suggested to select PGV as seismic strength index.
【學位授予單位】：中國地震局工程力學研究所
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：TU352.11;TU375.4

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本文編號：2247524