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1.
冯天民 《粮食储藏》1999,28(5):41-44
24m跨双曲薄壳板是集数学模型,高强钢材,高标号砼为一体的空间薄壳壁结构,是板架合一的新型屋面构件。近年来在粮食行业的库房建设中开始使用。实践证明,这种新型屋面构件具有结构合理,技术经济指标先进等特点,使用效果良好。  相似文献   

2.
The objective function of minimum cost is established for double layer torsional reticulated shell, taking the rise-span ratio, grid size and shell thickness as design variables. Based on the exhaustion and 0.618 methods, the computing program LSD has been developed. For the double layer torsional reticulated shell with the span of 50 m to 80m, the optimal grid size and thickness have been obtained for systems of light roof materials with different spans. Empirical formulas are deduced from the results.  相似文献   

3.
According to different construction ways and materials, three kinds of roof, that is ,passive evaporated roof with freedom water surface , water stored roof by means of pore material and hygroscopic roof,are introduced in this paper . Meanwhile the theory of heat insulation and energy efficiency on passive evaporation roofs and suitable weather and places to be used are also discussed .The results show that all kinds of passive evaporated roofs have high efficiency in heat insulation because of water's high specific heat and large quantity of absorbed latent heat,and that they can be adopted according to the practical local weather ,natural resource and economical development.  相似文献   

4.
屋顶农业栽培基质配比的筛选及对生菜生长、品质的影响   总被引:1,自引:1,他引:0  
本文通过屋顶栽培试验,在保持生长环境相同的条件下,对7种不同配比基质的理化性质及其对生菜生长情况和品质的影响进行了研究,同时运用灰色关联法对各基质的效果进行综合分析。从而为筛选合适的屋顶农业轻质基质提供理论依据。结果表明,各配比处理基质的容重为0.38~0.60g/cm3,总孔隙度为54.77%~74.17%,EC为242~1150 μs/cm,其中花生壳和蘑菇渣的加入可显著降低容重、增加孔隙度,牛粪和草炭对基质养分含量影响最显著;相对于CK,不同配比基质促进了生菜生长,其中T4、T5处理显著提高株高、叶长和干、鲜重;T5对提高生菜的可溶性糖和可溶性固形物含量最为明显。综合各项指标通过灰色关联法分析,T5(V(花生壳):V(牛粪):V(蛭石):V(珍珠岩):V(草炭)=2:2:2:2:2)处理适合屋顶农业中生菜的栽培,效果最好,可以作为屋顶农业中优良的轻质基质配方。  相似文献   

5.
Green roof plays a critical role in regulating roof runoff by reducing runoff, delaying runoff generation, reducing runoff peak flow and improving runoff water quality effectively. On the basis of introducing significance and role of green roof, this paper reviewed domestic and international researches on the green roof's control over roof runoff, and analyzed the factors that influence the control of green roof over the runoff, so as to provide a theoretical support and method for the construction of green roofs in urban districts.  相似文献   

6.
屋顶绿化的简史、现状与发展对策   总被引:13,自引:0,他引:13  
王军利 《中国农学通报》2005,21(12):304-306
屋顶绿化、屋顶花园虽然发展较早,但人们对它的要求日益迫切,通过对全国一些地方特别是 湖南长沙市的屋顶绿化和屋顶花园建植过程进行研究后发现,各项相关的科研、政策、法律法规发展 相对较慢,从而引发了诸多矛盾和不良后果,在调查研究的基础上,通过科学分析得出,为了使屋顶 绿化和屋顶花园健康持续地发展,从而充分发挥其应有的生态、环境、社会效益,应采取以下几个策 略:(1)加大施工队伍的设计、施工等技术培训,(2)加大政府监管,(3)加大政策和法律指导,(4)加强科 学实验。  相似文献   

7.
Considering the compression of medium and fluid, coupled vibration of saturated fractional derivative type viscoelastic soil and a circular tunnel with partially sealed shell lining in the frequency domain is investigated according to theories of Biot and elastic shell. The stress and displacement constitutive behavior of the soil skeleton is described by fractional derivative model which reflects the rheological properties of the medium while regarding soil as a liquid-solid saturated porous medium. The expressions of displacement, stress and pore water pressure are obtained while the inner boundary of circular tunnel is subjected to axially symmetric radial traction and axially symmetric fluid pressure respectively by introducing a partially permeable boundary condition. With the parameter analysis, it is revealed that the order of fractional derivative model on the responses for the system subjected to the symmetric radial traction is much greater than that of the system under the axially symmetric fluid pressure. And resonance phenomenon occurs obviously. Nevertheless the system responses do not have remarkable resonance phenomenon under axially symmetric fluid pressure.  相似文献   

8.
分析了彩钢板屋顶高大平房仓喷涂太阳热反射隔热涂料对仓顶温度、仓温、粮温的影响,为彩钢板屋顶高大平房仓控温储粮寻找一种有效方法。试验结果表明,喷涂太阳热反射隔热涂料对控制彩钢板屋顶高大平房仓仓温效果明显,同时可以达到延缓仓顶彩钢板老化、改善仓内工作环境和节能减排的目的。  相似文献   

9.
By exploring the space and the design techniques of roof garden in Frank Gehry's Walt Disney Concert Hall, this paper made further research on the combination of architectural functions and pedestrian fl ow lines, and attempted to summarize the unique design techniques of Frank Gehry by analyzing his works, improve and develop design theories of roof garden, and attract more attention from the public to roof garden design.  相似文献   

10.
This paper discusses the mechanism of the reduction ofheat flux through a roof pond with floating plants.A thermal model ispresented and the analytical results are obtained.The results are ingood agreement with the experimental observation.  相似文献   

11.
In view of the problems of architectural eco-civilization in Ningbo City against the background of "sponge city", this paper proposed that development of roof greening in the city met the development concepts of sponge city, summarized six basic countermeasures and four cooperation mechanisms for the developmental application of roof greening in Ningbo City by analyzing practical experience of roof greening construction in foreign countries.  相似文献   

12.
蛋壳主要由石灰质真壳和壳下膜2个部分组成,石灰质真壳中含有大量碳酸钙,是一种天然绿色的钙源;壳下膜中含有N-乙酰氨基葡萄糖半乳糖硫酸软骨素、氨基酸等多种可溶性高分子化合物。如何能采取方法对壳膜进行有效分离,使其物尽其用,可以充分挖掘蛋壳中潜在的利用价值,还可以从源头上减少垃圾排放量,有利于保护赖以生存的生态环境。通过介绍目前国内外3种壳膜分离的方法,阐述了每种方法的优缺点,为有效利用蛋壳壳膜资源提供了科学依据。  相似文献   

13.
In this paper artificial neural networks are used for design of large span double layer torsional reticulated shell. The torsional reticulated shells with spans varying between 50.0 - 80.0m are considered, Back -propagation algorithm is employed for training efficient neural networks for evaluation of the maximum deflection, weight and design of double layer torsional reticulated shell. A special method is developed for data ordering to reduce the nonlinearity of data and to increase the speed of training. This approach also provides the necessary stability. It shows that it is feasible to design double layer reticulated shell with artificial neural networks.  相似文献   

14.
This paper illustrates the existent of universities. Discussing the necessity for colleges issues in the traditional personnel management system in colleges and and universities to open out HRMIS, the paper puts forward the aims of soft development concerning HRM. According to the practice of the human resource management and exploitation in colleges and universities, the frame and functions and system implement of HRMIS founded on date-base based Web and E2Q business flat roof in universities are brought forward.  相似文献   

15.
This paper has simulated numerically the 2D temperature field and stress field of main circle pump shell steel castings of nuclear power plant by finite element method,predicts the dispersed shrinkage,shrindage and hot hearing.The real dissecting pouring castings had the same results as the numerical simulation.At the same time the authors evaluat the molding design of the pump shell castings.  相似文献   

16.
葵花子皮中水溶性膳食纤维初步研究   总被引:2,自引:1,他引:1  
为了提高葵花子皮中水溶性膳食纤维得率,在单因素实验基础上,通过响应面法对水溶性膳食纤维提取工艺进行优化研究。结果表明:提取瓜子皮中水溶性膳食纤维的最佳工艺参数为NaOH的质量分数为7.83%、提取时间为69.46 min、提取温度为42.10℃、液料比为40 mL/g;在最优工艺条件下水溶性膳食纤维的得率可达31.1112%,同时经测定得知葵花子皮膳食纤维具有良好的持水性和溶胀性:持水性为7.293 g/g,溶胀性为3.997 mL/g。因此瓜子皮可以作为提取水溶性膳食纤维的良好来源。  相似文献   

17.
以"陕秋白"大白菜成熟叶球为试材,研究了低温条件下4种保鲜液的保鲜效果.结果表明,在保持切割白菜9分水平上,各处理的效果依次为D>C>ck>B>A;在7分水平上,各处理的效果依次为D>A>C>ck>B;在5分水平上,A、C、D处理效果相近,高于对照,处理B与对照相近.总体比较,0.01%NaHSO3的D处理和0.01%NaClO的C处理保鲜效果较好.并对保鲜期间出现的褐变、霉变、愈伤组织等现象进行了分析与讨论.  相似文献   

18.
Roof planting is widely recognized as a ecological thermal insulation for roof. A lightweight green roof in climatic conditions of shanghai was investigated as a case study by applying PMV index to calculate thermal comfort compared with that with traditional roof in air conditioning. It is found that the PMV value of green roof is 0.2 lower than that of traditional roof, while the fluctuating range of green roof was only 1/4 of that of traditional roof. And the equivalent thermal insulating roof of green roof was obtained by computing. Furthermore, it is shown that green roof has lower interior surface temperature than equivalent insulating roof in the condition of higher indoor temperature.  相似文献   

19.
针对深部大跨度切眼顶板自稳能力差、变形剧烈、支护困难等问题,以赵固二矿1105大采高工作面切眼支护为工程背景,综合现场调研、理论分析、顶板探测等方法,分析了深部大跨度切眼冒顶机理和不同顶板的控制关键,提出了以接长锚杆支护为主导的顶板分区控制技术,阐明了不同顶板分区的控制原理。据此,对赵固二矿1105切眼二次成巷进行了支护设计,并进行了顶板下沉量和顶板失稳垮落规律监测,结果表明:接长锚杆与中部层位顶板共同形成的“锚固体岩梁”呈现出较好的稳定性,各层位顶板均得到了有效控制,保证了切眼顶板安全与正常服务。  相似文献   

20.
Thermal performance of the green roof is an important basis for energy-efficient design and evaluation. However, the current studies on the thermal performance of the green roof seldom involve thermal inertia of the green roof. Based on a long-term experiment of an extensive green roof in natural ventilation state and a five-month ongoing measured data in summer, thermal inertia of the extensive green roof was studied by statistical analysis method. The results show that thermal decay to outdoor climate effect through green roof was increased by more than 100% and delay time of thermal response to outdoor climate on internal surface of the green roof was reduced in comparison with that of the bare roof.  相似文献   

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