Study on Heat Insulation and Use of Passive Evaporated Roof

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.     

Wind Power Utilization Efficiency on Roof of Rectangular Buildings

Installing small wind turbines on the roof of buildings is a new way of wind power utilization in recently years. Based on the annual mean wind speed, the efficiency of wind power utilization on roofs of buildings was studied and the evaluation indexes for the utilization efficiency were proposed. With the help of CFD numerical analysis, the analysis on wind power utilization efficiency on flat roofs of rectangular buildings was carried out. The performance indexes of reference points under different windward angles were investigated. The best position and arrangement of wind turbines on the roof were also discussed. Furthermore, the utilization efficiency of four roofs with different shapes were analyzed and compared with that of flat roof.     

冬季自然条件下12种屋顶绿化木本植物抗寒性分析

为探索屋顶绿化木本植物的抗寒能力,筛选出耐寒强的屋顶绿化木本植物,在2010年12月、2011年1月和2月冬季自然降温条件下,结合实地观测屋顶和地面温度、风力、相对湿度等气象因子,采用电导法,分别对12种木本植物1年生休眠枝条细胞膜透性进行测定。结果显示,石家庄冬季屋顶比地面温度高、风速大、相对湿度低。构树、柳树、金银木抗寒能力强,‘金叶’榆、桑树、杠柳、白榆、小叶杨、‘金叶’女贞抗寒能力较强,珍珠梅、棣棠、红瑞木抗寒能力较弱。运用电导法评定屋顶绿化木本植物抗寒性是可靠的,为快速筛选抗寒性强的屋顶绿化木本植物提供了参考依据。     

拱板仓屋面喷水储粮安全度夏效果研究

针对拱板仓储粮度夏粮温偏高、分层明显和温差较大的特点，利用自来水自动循环装置对仓顶屋面进行喷水降温，最大限度地减少了盛夏仓顶曝晒后的积热，缩小了仓顶与粮堆之间的温差，延缓了粮温的上升速度，从而有效地改善了储粮在盛夏的高温环境，抑制了害虫的生长繁殖和粮食品质的陈化，是拱板仓储粮安全度夏的有效方法。     

Wind-induced Response Analysis on a Large-span Membrane Roof by Considering Non-gaussian Stochastic Wind Pressure Field

The stochastic fluctuating wind pressure field acting on a large-span membrane roof consists of Gaussian and non-Gaussian regions in the sense of statistics. Simulation of this stochastic field is presented based on the zero memory nonlinearity (ZMNL) transformation method. A case study is then given to show that the stochastic wind pressure field samples generated by the proposed method can well represent the specified statistical characteristics of data from the wind tunnel experiment. After that, the wind-induced response analysis is conducted on a membrane roof structure using the Gaussian/non-Gaussian composed wind pressure field samples generated by the proposed method and the Gaussian samples by the traditional method, respectively. Results indicate that response values of some components of the structure induced by the Gaussian samples are lower than those by the Gaussian/non-Gaussian composed wind pressure samples, which means the non-Gaussian characteristics of the stochastic wind pressure should not be ignored. Meanwhile, the total gust response factors of the components caused by the wind excitation are given to meet with the requirement of the designers.     

屋顶绿化木本植物的抗旱性研究

为了筛选出适宜屋顶绿化需要的节水抗旱木本植物,在2010年4-6月,以石家庄市的气候条件为基础,测定自然干旱胁迫条件下16种屋顶绿化木本植物的叶片面积、相对含水量、质膜相对透性、可溶性糖含量等指标,综合分析16种木本植物树种的抗旱性。结果表明,柳树、小叶杨、白榆、杠柳抗旱性最强,推荐用于屋顶绿化;金叶女贞、桑树、紫叶小檗、棣棠、红瑞木、珍珠梅、金银木、臭椿、大叶黄杨的抗旱性中等,通过精细管理也可用于屋顶绿化;金叶榆、构树、火炬的抗旱性弱,建议选用时应加强灌溉措施。     

Analysis on Wind-induced Dynamic Response of Arched Corrugated Metal Roof

It is generally considered that the seismic response of arched corrugated metal roof is not the control factor of structure design because of its light dead weight, but the wind-induced dynamic response on the structure is significant, so more attention must be paid to it. First, the wind simulation of the structure by AR model is carried out. Then, the TRANS method in the ANSYS is used to calculate the dynamic responses in time domain to compare the results with those in frequency domain in order to verify the validity of the two methods.     

Wind Tunnel Tests of Long Span Half - through Arch Bridge Section Model

Wind induced vibration is one of the main control factors in the Long span bridge structure design. The wind tunnel tests for measuring the static wind forces on the bridge girder and the section model wind tunnel dynamic testing for Caiyuanba Yangtze River Bridge in Chongqing are introduced in this paper. The wind tunnel testing for measuring static wind forces and vortex- induced vibration test on the arch are introduced taking account of the influence between two arches. The main contents and outcomes of testing are presented. It is indicated that the bridge girder has excellent wind stability and the arch mechanical characters are rather complicated. The drag force on the hind arch varied a lot because of the font arch interference on the wind flow. The drag force on the hind arch will be negative when two arches are close to each other. It increases with the space of two arches. The results of testing will give the data of buffeting and vortex - induced vibration and flutter analysis of the bridge.     

Loading behavior analysis of an aluminum alloy roof structure system under wind loads

The numerical analysis of a conventional aluminum alloy roof system taken from an actual international airport under wind uplift is conducted. A two-step simulation analysis approach is proposed, which effectively overcomes the computational difficulties brought by the contact between panels and supports. Through numerical analysis of roof components, the failure mode of the roof connection and the load bearing capacity of the roof are obtained. And the efficiency of material strength in each component is evaluated as well. It can provide reference for the design and application of aluminum alloy roof structure.     

周边干扰对煤气柜表面风压的影响

根据刚性模型风洞测压试验所得数据,研究了不同的周边干扰条件下柜体表面平均风压系数的变化规律,对比分析了不同柜体间距时干扰效应的变化情况。研究结果表明:干扰煤气柜位于柜体的正前方时,柜体迎风面平均风压系数显著减小;干扰煤气柜位于柜体的正后方时,柜体背风面平均风压系数会增大;两煤气柜相互平行时,柜体背风面平均风压系数会减小;柜体间距会对干扰效应产生影响,干扰效应随着柜体间距的变化而发生变化;在迎风面与侧风面,规范值有较高的安全储备;而在背风面,其安全储备略有不足。     

Application of Green Roof in Relieving Urban Waterlogging: A Review

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.     

彩钢板屋顶高大平房仓仓顶喷涂反射隔热涂料的应用效果

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。     

On the Design of Roof Garden

Building roof garden can widen the green area and expand the green space effectively.It has the ecological function for improving the environment, beautification function for molding a person's sentiment and colorful practical function. It can promote the ecological balance of the city and optimize the environment for human residence to meet the needs of people to approach the nature and return to the nature. In designing roof garden, the favorite factors, such as wide field of vision, good illumination, large temperature difference, little pollution, small people flow as well as adverse factors concerning the field, bearing capacity, soil and wind power should be taken into account. In the meantime, to create an outer ecological space with abundant cultural connotation, it is necessary to take safety as prerequisite, ecology as basis,artistic quality as its core, function as its purpose and economy as its guarantee.     

8种屋顶绿化木本植物的耐热性比较

筛选适应屋顶特殊环境的木本植物,对于丰富屋顶绿化植物种类、发挥屋顶绿化的生态和美化功能具有重要的现实意义。高温胁迫是植物正常生长发育的限制因子,为了探索屋顶绿化木本植物的耐热性,研究其在屋顶高温环境下的适应能力,笔者以屋顶上生长的白榆、柳树、构树、杠柳、小叶杨、金银木和较适宜屋顶绿化的金叶榆、珍珠梅8种木本植物为试验材料,测定不同梯度热处理条件下叶片相对电导率,配合Forstst2.1统计分析,对8种木本植物耐热性进行了研究,结果表明：叶片经梯度高温处理后,处理温度与细胞伤害率之间呈“S”形曲线。通过Logistic拐点确定半致死温度LT50,由高到低依次为：杠柳65.30℃、金银木63.80℃、小叶杨57.85℃、柳树56.84℃、白榆55.87℃、珍珠梅49.94℃、构树44.81℃、金叶榆43.98℃。8种植物材料中,杠柳、金银木的耐热能力最好,柳树、白榆、小叶杨次之,珍珠梅、构树、金叶榆耐热性较差。     

The Building and Roof Garden

The roof garden has great functioning of smoothing the shortage of land resource in the city and making use of the land resource diversity and efficiently. It is an efficient and reasonable way to exploit the open space the roof of the building. From the classic roof garden of the world, we can find out that roof garden has close relationship with the building. Roof garden is different with other kind landscape in the city, it needed cooperation of landscape architect and architect from at the stages of design, construction, upholding and management. We should attach importance to roof garden in the construction of building.     

Wind Loads Distribution on Typical Vaulted Shells

The distribution characteristics of shape factors and fluctuating wind pressure coefficients on two vaulted shells were investigated by simultaneous measurement of external and internal wind pressures on static models in wind tunnel. The effects of orifices on bottom and blocking at ends on wind loads distribution are discussed. It is shown that the wind pressure distribution is significantly affected by changes on orifices at bottom and blocking at ends. Wind pressure on ends decrease effectively and wind pressure on surface is distributed smoothly by blocking ends with highly curved surface shell. Small orifices at bottom not only contribute to degreasing negative pressure because of count acting effects of internal and external pressures, but also to extending the positive pressures region and increasing positive pressures. Wind loads suggestions on these structures are described at end.     

山区桥址处CFD计算域的选取方法

山区桥址处风场具有较强的随机性与不确定性,在选取其CFD计算域时,盲目参考已有的工程可能会造成较大的模型误差,或增加大量的计算开销。为解决该问题,提出了山区复杂地形CFD计算域选取的方法与步骤,验证了其准确性。具体方法为：设置一个大范围的基准计算域进行初算,通过后处理软件绘制平均风压系数极差随高度的变化曲线、壁面附近水平面上的静压偏差等值云图以及横风向各平面静压值与对应边界面的均方根差值曲线,分别筛选出基准计算域在高度方向、顺风向及横风向上对整体风场贡献可忽略的区域,余下部分则可用于该区风场的求解。     

Aerostatic stability analysis of long span half-through arch bridges

The main arch of a long-span arch bridge is a compression member. The static wind loads on the bridge not only causes changes of dynamic characters, but also leads the structure to collapse or buckling. Especially, when the arch bridge has longer span and less lateral braces,its stability is much different from the long span cable-stayed bridges and suspension bridges. This paper takes Chongqing Caiyuanba Yangzi River Bridge as a typical example and conducted the wind section tunnel tests. The displacement response of the bridge is obtained and its yield and static stability mechanism under static wind is analyzed. The results show that those factors, such as initial attack angle of the static wind, material yield strength and the static forces coefficients, have great effects on the aerostatics stability of a long span half-through arch bridge.     

Dynamic Heat Transfer Analysis of a Water Storage Roof

On the basis of analyzing the complicate heat and humid exchange between the outdoor air and the water layer of the roof,the authors obtained a heat transfer model and it's transmit matrix. The temperature and heat flux responses of the internal roof surface is greatly lowered than that of non-water layer roof. It can be concluded that the maintenance of a water layer on the roof is a good way to resist the fluctuation of outdoor temperature and significantly reduce the cooling load of a building.     

Analysis on the mechanical model in gob-side entry retaining of inclined coal seam

When gob-side roadways in inclined coal seam are retained by strike long wall mining method, the conveyor roadway are retained under ascending mining and the ventilation roadway is retained under underhand mining. In order to research the differences of roof activity in the two conditions, stack continuous layer boards model and load strips segmentation method are used and the influence of the coal seam dip angle is considered. Then the solving formulas of roadside support resistance under such conditions are obtained. Through comparison and analysis, it shows that roadside support resistance of conveyor roadway gob-side entry retaining is much greater than ventilation roadway gob-side entry retaining. When ventilation roadway gob-side entry retaining is used, roadside support resistance reduces with the coal seam dip angle increases. While conveyor roadway gob-side entry retaining is adoptel, roadside support resistance increases with the coal seam dip angle increases. But when the coal seam dip angle is larger than the natural repose angle of goaf caving gangue, the resistance can be reduced by considering the effect of goaf gangue accumulation. The conclusion provides reference for choosing mining sections order of gob-side entry retaining in inclined coal seam.