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991.
文章介绍了夹套反应釜的类型及受力分析,对夹套反应釜的实际操作受力情况进行了归纳,提出了夹套反应釜内简壁厚的设计关键是确定设计压力.总结出其设计思路和方法,在实际生产中得到验证。 相似文献
992.
Suksun Horpibulsuk Cherdsak Suksiripattanapong Anek Niramitkornburee Avirut Chinkulkijniwat Theerasak Tangsutthinon 《Geotextiles and Geomembranes》2011,29(5):514-524
This article presents the performance of a fully instrumented test wall reinforced with bearing reinforcement. Bearing reinforcement is an inextensible earth reinforcement. It is composed of a longitudinal member and transverse members. The longitudinal member is a deformed steel bar and the transverse members are a set of equal steel angles. The test wall was 6 m high, 9 m long at the top, 6 m wide at the top, and 12 m long, 21 m wide at the base and was constructed on a hard stratum. The facing panels were made of segmental concrete block which measured 1.50 × 1.50 × 0.14 m in dimension. From the full-scale test results, the bearing stress distribution is a trapezoid shape as generally assumed for the examination of the external stability of MSE walls. The tilt of the bearing reinforcement earth (BRE) wall indicates that the BRE wall behaves as a rigid body. The coefficients of earth pressure decrease with depth and approach the active state at deeper reinforcement level. From the variation in the stiffness factor as a function of depth and lateral earth pressure, the bearing reinforcement has a stiffness factor of K/Ka = 1.7, which is much lower than that of steel grids and metal strips. The lower tension (coefficient of lateral earth pressure) reduces the cross-sectional area of the longitudinal members and hence cost effectiveness. The maximum tension line (possible failure plane) of the BRE wall is bilinear, similarly to the coherent gravity structure hypothesis, which is commonly used for the analysis of inextensible reinforcements. Finally, the suggested method of designing the BRE wall is presented. It has been successfully used to design several BRE walls founded on the hard stratum in different areas in Thailand. 相似文献
993.
Cavity walls are often proposed in the building envelope design as a solution for improving the thermal comfort of the occupants and reducing the adverse condensation effects on the building fabric. Although the behaviour of a non‐ventilated cavity wall is well‐known, more studies are required when cavity ventilation is allowed. In order to consistently predict the thermal behaviour of a naturally ventilated cavity wall, a convective model based on the integral equations of motion and enthalpy was developed and applied in the present study. The model is presented as a combination of two limiting cases of a steady laminar flow into the channel gap: fully developed flow and boundary layer flow. Conduction effects across the system are also included through a proper limiting case and then combined with the convective model. In addition a numerical CFD model was developed that provides solution for free convective flow configurations between two parallel conducting vertical walls. For comparison purposes, some test cases were simulated with the two models and a general good agreement was found between results. Finally, the integral model was applied to assess the thermal performance of a ventilated cavity wall for winter and summer conditions. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
994.
从轻骨料免拆保温墙模复合剪力墙结构体系的特点出发,说明了其施工工艺的特殊性和复杂性,重点研究了本体系墙模砌筑主要工序内容,提出了施工工艺,并总结了本体系施工工艺中的施工难点,以期促进该结构体系的推广及应用。 相似文献
995.
建筑外装饰中越来越多地使用单元式幕墙,但设计人员对其认识与理解也或多或少有些差异。本文论述了单元式幕墙系统在节点设计中所存在的若干问题及解决方法。 相似文献
996.
997.
Thermal inertia of newspaper sandwiched aerated lightweight concrete wall panels: Experimental study
A short term experimental investigation on the thermal inertia: time lag and decrement factor of aerated lightweight concrete (ALC) wall panels is the main purpose of this study. ALC wall panels of different density and different aerial intensity of newspaper sandwiched were produced and erected on a prototype house. All wall panels were installed facing east direction and subjected to natural environment or tested under transient condition. The inner and outer surface temperatures of the wall panels were recorded at 3 min interval, 24 h a day. Time lag and decrement factor were computed from the surface temperatures recorded. The results showed that newspaper sandwiched ALC panel has greater time lag and lower decrement factor compared to ordinary ALC panel. It is found that time lag and decrement factor were influenced by the thermal diffusivity value of the wall panel. The thermal inertia property of the panels was negatively related to its thermal diffusivity. 相似文献
998.
近年来,建筑幕墙被广泛地应用于公共建筑。幕墙支承体系各式各样,其中,刚性、柔性钢结构组合体系以其独特的特点受到建筑业人士的青睐。结合两个工程实例,阐述了该体系的应用特点。 相似文献
999.
1000.
This paper reports on an optimization of a building wall using genetic algorithms. The double objective of optimization is maximizing thermal insulation and maximizing thermal inertia. If insulation is easily quantified with thermal resistance, inertia is a criterion not characterized with a single parameter. Using the quadrupoles method, we propose the thermal capacitance as a way to quantify the inertia of the wall. Walls realizing the best trade-off between the two conflicting objectives are presented in a Pareto front. Optimal walls composition shows that the best layers disposition is massive layer at indoor side and insulating layer at outdoor side. An important and new result obtained in this study is that the optimal thickness of the indoor side massive layer is Λ/4 where the thermal wavelength Λ is an intrinsic parameter of the layer material depending on the period of oscillations. 相似文献