新型混凝土复合保温砌块承重墙抗震性能试验研究

发明一套新型的混凝土复合保温砌块,提出一种采用异形复合保温砌块组砌圈梁、构造柱模板的构造方式,有效解决了现有自保温砌块砌体结构中圈梁、构造柱的冷桥问题。通过对四组分别采用新型构造方式砌筑及按照传统方式砌筑的足尺混凝土复合保温砌体墙体进行水平低周反复荷载试验,对比分析两种墙体的破坏过程、滞回特性、延性、耗能能力以及刚度退化等抗震性能指标。试验结果表明:新型混凝土复合保温砌块承重墙具有与传统方式砌筑墙体相同的抗震性能。     

钢纤维增强异形柱框架节点受力性能试验研究

为了解决异形柱框架节点的薄弱问题,对核心区应用钢纤维增强的异形柱框架中节点与同条件下未用钢纤维增强的异形柱框架中节点进行拟静力试验研究,对比分析异形柱框架中节点试件的破坏特征、中节点核心区的箍筋应变、混凝土应变及异形柱框架中节点的受剪性能,研究钢纤维增强的异形柱框架节点薄弱部位受力性能。研究结果表明:应用钢纤维增强的异形柱框架中节点试件的破坏特征得到改善;在异形柱框架节点核心区掺入钢纤维可以降低加载初期中节点核心区的箍筋应变,中节点腹板在平行于剪力方向的箍筋应变大于腹板垂直剪力方向的箍筋应变及翼缘处的箍筋应变;在中节点核心区掺入钢纤维可提高腹板混凝土的主拉应变和异形柱节点受剪承载力。     

混杂纤维布约束混凝土柱力学性能的研究

通过对碳纤维布、玄武岩纤维布和玻璃纤维布混杂约束混凝土圆柱的轴心受压试验,测得了混杂纤维布约束混凝土的轴心抗压强度、峰值应变、应力-应变关系,分析纤维布混杂方式对混凝土约束效果的影响。建立新的混杂纤维约束混凝土柱强度模型和应力-应变全过程整体模型,通过与试验结果比较,发现新的模型计算准确,与Teng等的模型相比,不需要分段拟合,计算简单,且同样适用于单一纤维约束情况。     

SPSW选型对多层轻钢结构抗震性能影响分析

为研究钢板剪力墙(SPSW)对多层轻钢结构抗震性能的影响,文章通过运用有限元分析软件SAP2000建立了6层纯框架轻钢结构模型,以此为基础对结构分别布置了薄钢板剪力墙、厚钢板剪力墙、十字加劲薄钢板剪力墙,对比分析了3种结构模型在荷载作用下的自振周期、加速度及其地震响应.结果表明,在高烈度地震作用下,十字加劲薄钢板剪力墙结构综合性能最好,且具有经济性.     

城市道路景观设计中行为心理学的应用

从人的行为心理出发,研究了不同人群在道路绿地景观参与过程中的需求和禁忌,并以此为依据,分析了道路景观在不同行为主体影响下的城市道路空间、景观形式、节奏、色彩、交通设施等元素的设计方法,为城市道路景观设计提供参考.     

Experimental seismic evaluation of old concrete columns reinforced by plain bars

Concrete buildings reinforced by plain (smooth) bars are one of the special types of old reinforced concrete buildings that were generally built before the 1970s. As columns are generally the most important structural members of a framed structure, understanding their realistic seismic behavior is very helpful in estimating structural deformations, forces and energy dissipation capacities. Furthermore, in most of old‐framed building structures, columns play a key role in the final behavior because of strong beam–weak column conditions. This article reports the results of experimental monotonic and cyclic tests on four concrete column specimens reinforced by plain bars and with various types of splices. Through the experimental results, it tried to obtain more clarification on the complicated behavior of such old reinforced members as well as the differences compared with relevant results of columns reinforced by deformed bars. It was realized that slip (fixed‐end rotation) contribution is the major source of deformation in all specimens independent from type of splices. Moreover, general mode of behavior was restrained‐rocking action independent of type of splice detailing. A simple theory for the explanation of hysteresis force–displacement response was proposed. The theory assumes a concrete block rocking element that is restrained with plain bars at both ends. Copyright © 2010 John Wiley & Sons, Ltd.     

弯曲宽箱梁剪力滞分析

该文介绍了曲线梁与直线桥区别和剪力滞效应,运用有限元软件对弯曲宽箱梁受力性能进行了分析,得出了其在自重作用下应力状态和支座处剪力滞效应规律。通过计算得出,在一定曲率半径范围内,弯曲宽箱梁在自重及偏心车道荷载作用下顺桥正剪力滞系数有较好的规律分布,最大值一般在4左右,以及外侧支座处剪力滞系数大于内侧。     

高分子链结构对聚酰胺酰亚胺溶液流变行为的影响

以高分子主链分别含3个和10个亚甲基结构的脂肪族–芳香族聚酰胺酰亚胺(PAI)为模型聚合物,采用旋转流变仪研究了高分子链结构对PAI溶液流变行为的影响。研究结果表明,含10个亚甲基结构的PAI在较宽的剪切速率范围内表观黏度变化不大,但含3个亚甲基结构的PAI溶液在一定的剪切速率区间发生了剪切增稠现象,并且随着温度的升高,剪切增稠现象逐渐减弱,同时剪切增稠所对应的剪切速率向高剪切速率方向移动。     

弹性聚酯复合纤维的定性方法研究

通过燃烧法、显微镜观察法、差示扫描量热仪法研究了弹性聚酯复合纤维的外观形态及物理特征,确定了弹性聚酯复合纤维的定性鉴别方法。     

Mechanical behavior of Ce0.9Gd0.1O1.95-La0.6Sr0.4Co0.2Fe0.8O3−δ oxygen electrode with a coral microstructure for solid oxide fuel cell and solid oxide electrolyzer cell

The objective of this work is to investigate the mechanical behavior of CGO-LSCF composite developed by electrostatic spray deposition as an oxygen electrode for Solid Oxide Fuel Cell and Solid Oxide Electrolysis Cell. The coating is characterized by a highly porous morphology designated coral microstructure. Its mechanical behavior was studied by scratch and ultramicroindentation tests and a model of material degradation under progressive compressive loading has been proposed. The coral's damage mechanism involves three regimes: at very low loads stresses are concentrated at the tips of individual corals that fracture and fill the spaces between corals (regime I); as load increases, generalized fracture of the corals occurs and the material starts compacting into an increasingly dense layer (regime II); finally, at the highest loads, the material behaves like an almost fully dense (regime III). As load increases during testing porosity decreases from about 60 to about 5 vol% in the compacted material. The transitions between regimes are associated to increases in the contact stress and the same damage mechanism is found during scratching and indentation. Hardness increases from about 2–100 MPa, while the Young's modulus varies in the range 1–18 GPa, as the porosity decreases. Calculations of the real contact pressure during loading allowed estimating a yield stress of 83 MPa that can be considered as a low limit for the materials fracture strength.