【作者】 李翔；

【导师】 王莹；

【作者基本信息】 福州大学 ， 建筑与土木工程（专业学位）， 2022， 硕士

【摘要】 双钢板-混凝土组合剪力墙具有抗压强度高和抗弯能力强等性能优点。不锈钢复合钢材兼具低成本与高耐腐蚀性能,超高性能混凝土(UHPC)具备超高强度、高耐久性的优点。将不锈钢复合钢板和UHPC运用于双钢板-混凝土组合剪力墙,可以解决传统组合剪力墙耐腐蚀性弱和核心混凝土延性差等问题。本课题对高强钢板-UHPC-复合钢板组合剪力墙进行试验研究、数值模拟和理论分析,系统地研究了组合剪力墙轴心荷载作用下的受力机理。具体内容为:(1)进行了18个高强钢板-UHPC-复合钢板组合剪力墙的轴压试验,研究了抗剪连接键的距厚比、长细比、钢板厚度、混凝土强度和UHPC钢纤维掺量等参数对破坏形态、荷载-位移曲线、屈曲应力等结果的影响。研究表明:试件伴随着混凝土的压溃和钢板的贯通鼓曲被压坏;UHPC极大地提高了组合剪力墙的轴向承载力和刚度,钢纤维延缓了混凝土裂缝的扩展;复合钢板较高强钢板先达到屈服强度,且高强钢受到的应力随着距厚比的减小而增大;栓钉和对拉筋的间距过大会使钢板和混凝土过早地发生界面分离,减弱材料之间的协同作用。(2)采用ABAQUS软件建立了以实体单元、壳单元和梁单元为组合用于分析双钢板-混凝土组合剪力墙轴压的精细化有限元模型,并通过试验结果对有限元模型进行较准。将较准后的有限元模型进行力学性能研究和参数分析,研究了两种材料的承载能力、钢板和混凝土在试件失去承载力前后的受力性能以及栓钉和对拉筋的受力情况;分析了剪力连接键形式、材料强度、含钢率和距厚比等参数对组合墙受力性能的影响。结果表明,与钢板相比混凝土强度的变化对试件承载能力影响程度更大,距厚比、长细比对钢板的屈曲影响很大,长细比是决定钢板发生弹性屈曲或塑性屈曲的重要参数。(3)采用欧拉理论公式计算组合剪力墙钢板的临界抗压承载力,总结出高强钢板-UHPC-复合钢板组合剪力墙中复合钢板临界屈曲应力的计算公式;此外将Eurocode-4、CECS:546-2018和ANSI/AISC N690-18等设计规程中的计算公式结果与试验结果进行了对比分析,规范中对双钢板-混凝土组合剪力墙的计算值较为准确但不够安全。对于不同归一化长细比的组合墙试件,考虑混凝土贡献度的折减:当归一化长细比小于1.0时,混凝土贡献系数取0.85,归一化长细比大于1.0时,混凝土贡献系数取0.7。更多还原

【Abstract】 The steel-concrete composite wall(SC composite wall)has the advantages of high compressive and flexural strength.Low cost stainless-clad bimetallic steel(clad steel)has high corrosion resistance,and the advantages of ultra-high performance concrete(UHPC)include ultra-high strength and high durability.The application of clad steel and UHPC to SC composite wall could potentially improve corrosion resistance and ductility of core concrete.This thesis experimentally,numerically,and theoretically studied the axial compression behavior of an innovative high-strength steel-UHPC-clad steel composite wall(HS-UHPC-Clad steel composite wall).The detailed contents are:(1)The axial compression tests of 18 HS-UHPC-Clad steel composite wall specimens were conducted.The influence of parameters were studied,including cladding ratio,slenderness ratio,thickness of steel plate,concrete strength,and steel fiber content of UHPC.The failure mode,axial strength,load-displacement curve,load-strain curve,and buckling stress of the specimen were obtained through experiments.Typical failure mode was concrete crushing accompanied by buckling of steel plate.UHPC effectively improved the axial strength and stiffness of the composite wall,and steel fibers effectively controlled crack width.The clad steel plate with lower yield strength reached yielding strength prior to high-strength steel plate.The stress in the high-strength steel plate increased with increasing distance-to-thickness ratio.The spacing of studs and tie bars was an important factor to ensure the composite behavior between steel plate and core concrete.If the spacing exceeded the limits,steel plate and core concrete could be separated.(2)Detailed finite element(FE)models were built using ABAQUS with solid element,shell element and beam element to study the axial force transfering mechanism and conduct parametric studies.The FE models were calibrated using the test results.The behavior and contribution of steel and concrete before and after failure were studies,as well as the stress distribution of studs and tie bars.Parametric studies were conducted to study the influence of the type of shear connectors,material strength,steel content and distance-to-thickness ratio.The results exhibited that the change of concrete strength had a higher influence on the axial strength than the strength of steel plate.The slenderness ratio was an important parameter that determined the occurence of elastic or plastic buckling.(4)The critical compressive strength of steel plate is calculated using the Euler equation.The critical buckling stress of clad steel plate in HS-UHPC-Clad steel composite wall was studied and recommended.In addition,the calculated axial compressive strength using design provisions,such as Eurocode-4,CECS: 546-2018 and ANSI/AISC N690-18,were compared with the test results.The calculated strength are close to the test results while the safety margin was not enough.The following recommendation was made in this study.For composite wall specimens with different normalized slenderness ratios,the reduction of concrete contribution shall be considered.When the normalized slenderness ratio is less than 1.0,the concrete contribution coefficient shall be taken as 0.85,and when the normalized slenderness ratio is greater than 1.0,the concrete contribution coefficient shall be taken as 0.7.更多还原