【摘要】 部分包覆钢-混凝土组合墙（简称PEC墙）在装配式建筑领域具有广阔的应用前景，近年来在建筑结构中逐步推广应用，但其稳定性能方面的研究尚待完善。对PEC墙稳定性能展开研究，基于既有试验和有限元分析结果，考察计算长度、材料强度、主钢件钢板厚度、构件截面尺寸等参数对墙体稳定性能影响，提出PEC墙轴压稳定曲线计算公式，公式计算值与有限元结果吻合良好。采用有限元软件ABAQUS建立有限元分析模型，基于既有试验数据进行对比，验证模型准确性。之后，对PEC墙轴心受压稳定性能展开数值参数分析，考察构件各参数对其稳定性能的影响，包括：计算长度、材料强度、主钢件钢板厚度、构件截面尺寸等。参数分析过程采用控制变量法，逐个研究各参数对PEC墙体稳定性能的影响程度，总结受力特点及规律。基于组合结构的稳定理论，按组合截面中混凝土与主钢件的构成，综合确定组合截面的等效强度f_EQ、等效弹性模量E_EQ,并推导了PEC墙构件的正则化长细比λ_n。然后，基于有限元分析结果绘制PEC墙的轴压稳定曲线，将钢结构四类截面稳定曲线与PEC墙稳定曲线进行对比，总结规律，寻找适用于PEC墙构件稳定曲线的计算方法。最后，基于参数分析结果，总结各构件参数对PEC墙稳定曲线的影响，在PEC墙轴压稳定曲线的计算公式中引入关键构件参数作为控制变量，同时基于不同计算长度下构件破坏形态特点，提出了“三段式”PEC墙轴压稳定曲线计算公式。研究表明：1)构件计算长度l₀对PEC墙破坏形式有较大影响，随着l₀增加，构件破坏形态及其极限承载力由材料强度控制转变为整体稳定控制；2)PEC墙各构件参数中，主钢件翼缘厚度、构件截面厚度对稳定性能影响较为显著，材料强度、主钢件腹板厚度、构件截面高度等对稳定性能影响相对较小；3)国内外尚未颁布PEC墙体设计的相关规范，我国现行设计规范GB 50017—2017《钢结构设计标准》提供的四类截面稳定曲线均不适用于PEC墙轴压稳定系数的确定；4)提出了PEC墙轴压稳定系数“三段式”计算公式，公式计算值与有限元结果吻合良好，对不同材料、不同尺寸的PEC墙均可保持较高精度，可用于PEC墙轴压稳定系数的确定。更多还原

【Abstract】 Partially encased composite walls（PEC walls） have been widely used in the field of prefabricated buildings. In recent years, it has been gradually applied in building structures. However, the researches on the stability performance of PEC remain to be improved. In this paper, the stability performance of PEC wall under axial compression is studied. Based on the existing experiments, a finite element model is established. The influence of parameters such as calculation length, material strength, main steel section thickness and, section size of components on the wall stability is investigated, and the calculation formula of the PEC wall axial compression stability curve is proposed. The research shows that the calculated values of the formula are in good agreement with the finite element results. In this paper, the finite element software ABAQUS is used to establish a finite element analysis model, and the accuracy of the model is verified by existing experimental data. Then, this paper analyzes the the axial compression stability performance of PEC wall under parameters, and investigates the influence of different parameters on the stability performance of components, including calculated length, material strength, steel section thickness of the main steel parts, and the cross-sectional size of the components. The parameter analysis process adopts the control variable method to study the influence of each parameter on the stability performance of PEC wall, and summarize the mechanical characteristics and regulations. Then, based on the stability theory of the composite structure, the equivalent strength f_EQ and equivalent elastic modulus E_EQ of the composite section are comprehensively determined according to the composition of concrete and main steel parts in the composite section, and the regularized slenderness ratio λn of the PEC wall components is derived. Then, based on the results of finite element analysis, the axial stability curve of PEC wall is drawn, and the stability curves of four types of sections of steel structure are compared with the stability curve of PEC wall, the regulation is summarized, and the calculation method suitable for the stability curve of PEC wall components is found. Finally, based on the parameter analysis results, the influence of each component parameter on the stability curve of PEC wall is summarized, and the key component parameters are introduced as control variables in the calculation formula of the axial compression stability curve of PEC wall, and the calculation formula of the axial compression stability curve of the "three-stage" PEC wall is proposed based on the characteristics of the failure mode of the components under different calculated lengths. The results show that: 1) the calculated length l₀ of the component has a great influence on the destruction form of PEC wall, and with the increase of l₀, the destruction form of the component and its ultimate bearing capacity change from material strength control to overall stability control; 2) among the parameters of each component of PEC wall, the flange thickness and the section thickness of the main steel parts had significant effects on the stability performance, and the material strength, web thickness of the main steel parts, and the cross-sectional height of the components had relatively little effect on the stability performance; 3) the relevant specifications for PEC wall design have not been promulgated at home and abroad, and the four types of section stability curves provided by China′s current design code Steel Structure Design Standard（GB 50017—2017） are not applicable to the determination of the axial compressive stability coefficient of PEC wall; 4) the calculation formula of the axial compressive stability coefficient of PEC wall proposed in this paper is "three-stage". The calculated value of the formula is in good agreement with the finite element results, and can maintain high accuracy for PEC walls of different materials and sizes, which can be used to determine the axial compressive stability coefficient of PEC walls.更多还原