复合保温墙体传热研究

针对复合保温墙体传热问题 ,在分析其组成及传热特点的基础上 ,建立数学模型 ,并采用有限差分隐式格式求解。求解中结合实测数据进行数值计算 ,得到复合保温墙体内各点温度在外部温度扰动情况下随时间的波动值。计算结果与实测结果比较表明 :使用数值方法研究复合保温墙体的传热问题具有效率高、计算精度高的特点 ,能方便地用于解决优化建筑结构组成及分析热负荷或冷负荷方面的实际计算中     

利用化工废石膏与粉煤灰生产复合胶凝材料的开发研究

本文研究了热激发对化工废石膏—粉煤灰复合胶凝材料物理性能的改性作用。研究结果表明,采取低温煅饶激发化工废石膏的化学活性,可以较大幅度地缩短复合胶凝材料的凝结时间和提高强度,行之有效地改善复合胶凝材料的物理性能。     

预应力混凝土空心叠合板试验研究

针对现有的一般预应力空心叠合板楼盖板厚较大,自重较大等缺点,提出了一种新形式的预应力混凝土空心叠合板,通过对3块简支板,3块简支叠合板和1块两跨连续叠合板进行静力荷载试验,分析了这种板在静力荷载作用下的裂缝、承载力、挠度等特点,研究了其开裂荷载和极限承载力较高的原因。试验结果表明这种预应力空心叠合板具有良好的抗裂性能和较高的极限承载能力,建立了开裂弯矩、极限承载力、挠度的计算方法,为这种叠合板的设计和工程应用提供了依据。     

兰州某厂大厚度自重湿陷性黄土场地地基处理试验研究

采用钻孔夯密桩复合地基和人工挖孔灌注桩处理大厚度湿陷性黄土地基,取得了良好的效果,继续研究本课题的目的就是要通过对该场地几种地基处理方法的系统研究,并结合工程实践,为处理大厚度湿陷性黄土场地提供可靠的技术参数,以供参考。     

Moment-rotation-temperature curves for semi-rigid joints

Although connections are known to have a very significant effect on the behaviour of steel and composite framed buildings in the event of fire, the cost of high temperature tests on the broad range of connections used in practice means that their influence is not well detailed in current design codes. The paucity of data also limits the effective use of numerical models developed to simulate the behaviour of complete structures at elevated temperature. This research describes a series of elevated temperature tests conducted on beam-to-column connections. This paper presents moment-rotation-temperature curves for a variety of connections.     

钢渣桩加固软土地基的研究

介绍钢渣桩加固软土地基的机理、设计与施工 ,并对设计方法进行了简要探讨 ,指出钢渣桩加固地基很有开发利用价值和发展潜力 ,应加大研究 ,推广使用。     

Large-scale test of symmetric cold-formed steel (CFS)-concrete composite beams with BTTST enhancement

A new connection device, based on bent-up tab shear transfer enhancement called bent-up triangular tab shear transfer (BTTST), has been studied through a symmetric cold-formed steel (CFS)-concrete composite beam subjected to a static bending test. BTTST provides an alternative connector system unique to CFS where CFS sections are usually thinner than hot-rolled sections and welding of headed-stud shear connectors is inapplicable. Coupled with the back-to-back arrangement of two CFS channels where symmetricity of the built-up section is restored, the resulting composite floor system has been proven to possess adequate strength and stiffness properties under static loads. The work has shown that the predicted values of the flexural capacities calculated using a new equation of shear capacity of BTTST agrees reasonably well with the experimental values.     

新型预应力叠合楼盖的特点及其工程应用

新型预应力混凝土叠合楼盖是目前正在研究探讨的一种优良的多功能叠合楼盖体系,其具有预制和现浇两种楼盖的优点。此楼盖由于其带肋预制构件具有较大的刚度和承载力,并且通过合理的构造实现了楼板的双向受力。对新型预应力混凝土叠合楼盖技术进行了简要的介绍,并针对该项技术应用于某学院教学楼的结构性能、施工方案和经济效果进行了详细的描述和分析。     

复合地基基本工作机理及存在问题综述

本文介绍了复合地基的发展现状、基本工作机理 ,并对复合地基的承载力计算方法和沉降计算方法进行了分析 ,最后对复合地基计算中存在的问题进行了探讨     

Design of semi-continuous composite steel-concrete beams at the fire limit state

A two-dimensional temperature analysis procedure based on the finite element method (FEM) is described and applied to steel-concrete composite beams. A computer program developed for the analysis is detailed. A strategy is also proposed for incorporating the influence of the partial resistance of the composite connections in reducing the sagging moment at central regions of the beam spans when the beam is calculated as semi-continuous. Finally, an example problem is discussed, comparing the design uniformly distributed loads that can be supported by a composite beam calculated as semi-continuous and with simply supported spans. The temperature distribution due to fire at the central region of the spans is taken as in the simplified procedure proposed in European Prestandard ENV 1994-1-2 [ENV 1994-1-2. Eurocode 4, Design of composite steel and concrete structures — Structural fire design. Brussels: European Committee for Standardization (CEN); 1994] and then obtained with the more rigorous calculation using the described numerical algorithm. It will be assumed that no ultimate limit state will occur due to shear force (web buckling) or due to bending moment at the hogging moment regions of the beam (web and bottom flange buckling or distortional lateral buckling).