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1.
Extra-cellular compounds, secreted by microorganisms into their surroundings, can be integrated in concrete composition as admixtures. These substances are important in biofilm formation and some of them can be used as corrosion inhibitor of concrete reinforcement. This paper deals with products made with biological surface active compounds/agents allowing the development of more eco-friendly concrete. The influence of this environmentally friendly bio admixture on setting time, workability, bending and compressive strengths of various mortar based materials made of CEM I, CEM III and CEM V was studied. Mechanical tests were carried out to highlight the influence of admixture in workability and hardening of samples containing the biological product with ratio in the range of 0-2.5%. It was demonstrated that the presence of the new bio-compound admixture in mortar decreases their compressive strength after 28 days of standard curing, in spite of remaining higher than standard minimal strength. Furthermore, Vicat needle experiments have shown a tendency of this admixture to decrease the setting time. A discussion was finally proposed in order to correlate the setting times and the decrease of the mortar compressive strength, corresponding in fact to a hardening delay. This setting time delay could be linked to a delay of the admixtured mortar to increase its resistance. The slump results highlight the action of bio-admixture as a plasticizer on mortars because it increases their workability for a same water-cement ratio. This effect seems variable according to the added amount.  相似文献   

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第3代循环式多轿厢电梯系统的设计概念   总被引:1,自引:0,他引:1  
郭亮 《中国电梯》2010,(7):30-34
运用现代成熟的电梯曳引技术在一条井道内运行多台轿厢,实现单位时间内最大的输送量,是长久以来建筑界对电梯界的期盼。循环式多轿厢电梯系统经历了第1代、第2代设计的演进,已经产生了类似于地面交通运输系统的第3代设计概念,从而建立了立体交通的新格局。  相似文献   

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提高公共交通竞争力的措施分析   总被引:2,自引:1,他引:1  
政府确立的公共交通优先发展战略实质,是想通过政府手段来提高公共交通在交通运输市场中的竞争力.在此基础上,提出了在自由竞争的市场环境中,各种交通方式间竞争关系的基本分析框架.并在该框架内,以出行距离来衡量交通需求,着重分析了公共交通与自行车基于时间成本上的均衡点和公共交通与小汽车基于出行综合成本上的竞争均衡点,并分别推导出相应的判别模型.根据判别模型推论各个影响因素与公共交通竞争力间的函数关系,提出相应的政策措施,并对各个措施进行评述总结.  相似文献   

5.
Commonly proposed concepts, like KBS-3V, for disposal of highly radioactive waste imply construction at medium depth (400-600 m) in granitic rock, which is excellent for constructing a stable repository. VDH (very deep boreholes) represent an altemative concept with the advantage that the rock is much less permeable and that the very salt, heavy groundwater is stagnant. Both require engineered barriers in the form of canisters and waste-embedding clay but for somewhat different purposes. Canisters are the most important waste-isolating barriers for KBS-3V but are less important for VDH. The waste-embedding clay is needed for preserving the KBS-3V canisters by being tight and ductile, but plays a minor role for the VDH. The backfilled deposition tunnels in a KBS-3V repository provide very limited hindrance of radionuclides to move to the biosphere while the clay seals of VDH effectively prevent possibly released radionuclides to reach up to the biosphere. Comparison of the KBS-3V and VDH concepts indicates that the last mentioned one has several advantages but that certain issues remain to be worked on for becoming a number one candidate.  相似文献   

6.
In the United States, university buildings use 17% of total non-residential building energy per year. According to the NREL (National Renewable Energy Laboratory), the average lifecycle of a building in a university is 42 years with an EUI (energy use intensity) of 23 kWh/m^2/y. Current building and energy codes limit the EUI to 16 kWh/m^2/y for new school buildings; this benchmark can vary depending on climate, occupancy, and other contextual factors. Although the LEED (leadership in energy and environmental design) system provides a set of guidelines to rate sustainable buildings, studies have shown that 28%-35% of the educational LEED-rated buildings use more energy than their conventional counterparts. This paper examines the issues specific to a LEED-rated design addition to an existing university building. The forum, a lecture hall expansion of to an existing building at the University of Kansas, has been proposed as environmentally friendly and energy-efficient building addition. Comfort and health aspects have been considered in the design in order to obtain LEED platinum certificate. The forum's energy performance strategies include a double-skin facade to reduce energy consumption and PV (photovoltaic) panels to generate onsite energy. This study considers various scenarios to meet NZEB (net-zero energy building) criteria and maximize energy savings. The feasibility of NZE criteria is evaluated for: (a) seasonal comparison; (b) facility occupancy; (c) PV panels' addition in relation to double skin facade. The results of NZEB approach are compared to LEED platinum requirements, based on Rol (return on investment) and PV panel's efficiency for this specific educational building.  相似文献   

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The goal of this study is to determine specific guidelines for Iraqi architects to contribute to the design and composition of energy-efficient housing units within the limits of a normal budget, locally available materials and technologies. These units can provide comfort despite the current energy situation in Iraq. The study is based on a computer simulation for a reference building in Baghdad, which has been selected according to the urban conditions, building legislations, housing market and statistics. The final results displayed the main recommendations and the possibility to achieve up to 50% energy reduction with a pay-back period not exceeding two years in some cases. There are some measures that have big energy saving potential. Yet, some of the measures may require big investment or have some bad environmental impacts. Some other good measures are already being implemented.  相似文献   

8.
The new architecture may provide unusual opportunities for the abandoned areas involved by former industrial processes, both in the city centers and in the landscape. In fact, it may create new centralities and give new collective function for deprived areas. The case study of the architectural and educational project for a new museum park devoted to the technique and the science in the Apennine' s landscape near Parma (Italy) may give an interesting point of view about the role of the teaching and the research of the architecture in the former industrial heritage, and to avoid the abandonment and the pauperization of the territory around.  相似文献   

9.
If Europe is to achieve the planned transition to a low carbon economy by 2050, succeeding in improving the energy efficiency of the largely inefficient existing building stock will be pivotal. Certain energy efficiency retrofitting obligations have now emerged as part of the EU's Energy Performance in Buildings Directive and the Energy Efficiency Directive. Challenges for retrofitting currently include gaps in technical skills both amongst building trades and professionals, a lack of awareness of building owners and users, concerns about compromising cultural heritage as well as a lack of viable business models, comparatively high cost and resulting long pay-back periods currently hamper the progress. Lessons can be drawn here form the EU-funded initiative CONCERTO, which helped 58 communities in 23 countries to reduce their dependence on conventional energy supply by implementing energy efficiency measures and integrating renewable energy sources not at single building scale but community scale. Almost all of these entailed retrofitting activities bad to find solutions to the issues mentioned. This paper presents a selection of conclusions regarding retrofitting to be drawn from the analysis undertaken under the project CONCERTO premium, which analysed outcomes across the 58 projects on behalf of the European Commission and focuses in particular on the political relevance of outcomes.  相似文献   

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In post-disaster emergency shelter aid, various relief agencies and other actors with different backgrounds need to cooperate in a tremendously short amount of time and under very different circumstances. In this article, we describe a research project that develops and tests a new approach in which the demands for shelters in a specific situation are methodically connected with available, innovative and sustainable shelter solutions, a DSS (decision support system). The DSS is a digital tool that translates the gathered evidence on needs, solutions and location including long-term effects of shelter provision into advice for the provision of sustainable, integral broader shelter solutions and designs. The outcome is a set of characteristics for a DSS for the provision of on-demand emergency shelters. A DSS that meets these characteristics leads to the provision of sustainable shelters that meet the needs of the users and, therefore, have higher performance in long term.  相似文献   

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运用离散优化方法,研究区域内各组团间运输通道网络优化设计问题,设定运输通道供给能力以及通道在区域之间的运输时间约束,构造综合运输通道投资建设总费用的优化模型,考虑各种运输通道的单位投资建设费用和建设长度的最优问题;利用综合运输通道的特点和区域组团网络结构进行算法设计,并给出最优解的多方案求解步骤;针对大规模节点采用遗传算法进行求解可以提高求解效率;通过一个算例,对模型和算法的可行性和有效性进行验证,说明该算法可得到综合运输通道的最优投资方案,使综合运输通道满足规划年的客货运需求,以及各种运输方式的平均出行时间满足要求,分析说明客货运输需求与运输通道建设的关系,结果表明提出的模型与算法对交通投资项目提供较好的辅助决策支持。  相似文献   

12.
Up to now, reuse and recycling of existing buildings have not been examined widely. This paper discusses the theories, methods and practicalities of buildings' end of life with a main focus on planning and managing reuse and recycling of existing buildings. Our aim is the realistic modelling of theoretical scenarios for end of life based on a case study. The methods of building survey, material classification and documentation for reuse, recycling and disposal of existing constructions are presented. Investigations and calculations were done on an existing cottage in the Alps. The ecologically most beneficial disposal phase of the old wooden hut is our main objective. Critical questions arise from the quality of the material and how it can be extracted, separated and balanced in an appropriate way. A systematic survey of the building by inspection of constructions and materials in iterative steps allows a detailed material balance with condition and property information. This information is crucial for scenarios and material flow analysis of demolished and rebuilt building in environmental system analysis. For future planning, the reuse and recycling of existing buildings should be integrated quite early in the planning process so that we can use the materials in the best way.  相似文献   

13.
Teaching design incorporating a sense of sustainability to architecture students is a challenge today, primarily because of the trend to label every design as sustainable or green even though it is no different from a more traditional one. The result is a "green-washed" education in architecture. To address this issue, this paper describes a teaching methodology of architectural design with a special focus on sustainability implemented in the Graduate School of Architecture in Clemson. This method includes an analysis of the location, the climate conditions, the materials needed and the construction process. Knowing that sustainable design is generally perceived as being expensive, there is a special focus on simplicity and affordability. Rather than relying on expensive technical solutions, students are encouraged to design for the given environment and apply passive strategies. In the approach discussed in this paper, the design process is a number of logical scientific decisions rather than an intuitive draft. The goal of this pedagogy is to raise awareness about how to handle global resources carefully and to show the importance of the later performance of the project as a key to design. The teaching strategy is described here along with the successful participation by our graduate students in a number of refereed competitions.  相似文献   

14.
During the 1960s, many changes reshaped the economy, the society and the arts. The Cold War, the Space Race, the construction of a new middle class in most western societies led by the postwar economic prosperity with unprecedented urban growth followed by severe environmental problems fostered the design of spectacular urban utopian cities and mega-architectures. In those years, Japan was the source of highly influential bold and visionary urban and architectural ideas which relied on advanced technology. These ideas were conceived on the thought that cities could be seen as gigantic but impermanent entities able to transform itself according to an organic process of adaptation of its elementary components. This paper briefly revisits and critically discusses the legacy of the iconic mega-strnctural projects of Japanese Metabolist Movement and other visionary architects and planners of the 1960s, such as Paolo Soleri, Buckminster Fuller, Archigram. It attempts to enlighten the continuity with contemporary innovative and experimental urban models and ideas for the society and the city of the future, such as the Smart Cities, Eco-Cities, Green Urbanism, whose design is led by concerns related to climate change, the necessity of energy efficiency, the improvement of urban landscape and the valorization of depleted natural resources.  相似文献   

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Combination of a bus system and cable car system can reduce the overall congestion of traffic in urban areas, where surrounding hills or mountains hold larger settlements or tourist and recreational infrastructure. With this kind of integration number of individual car trips can be significantly reduced. In this paper, the authors present an analysis of the pilot project implementation, which was held in Maribor. The authors conducted a limited test trial of two means of transportation, combining them into a single operating transport offer for inhabitants and tourists. Combined transport option proved to be a good starting point for reduction of traffic and parking congestion during winter tourist season and beyond. Method used in the research, in order to gain actual potential of integrating two systems and improving public transport offer, was establishment and implementation of the pilot project in Maribor during January 2011. Data was gathered through interviews of two interest groups. The first covered the users who were brought to the foothills of Pohorje's ski center by bus. The second covered the cable car users that were traveling to the top of Pohorje. For a limited time period, a trial principle of a single ticket was established, which gave ski-pass holders free bus ride on bus line No. 6. With the aim of reducing CO2, test drives of hybrid bus and compressed natural gas bus were conducted alongside many promotional activities with which users were informed of importance of environmentally friendly mobility options.  相似文献   

17.
The partial substitution of clinker by mineral additions offers very significant, both economical and environmental benefits. This adds value to industrial waste, and contributes also in the preservation of natural resources, like clay and limestone, as well as the reduction of greenhouse gas emissions (CO2). This study is interested in the simultaneous effect of BFS (blast furnace slag) and SF (silica fume) on setting time and water requirement of cement paste. The volumetric variations are tested in mortars, prepared in the same mixture of pastes, and the tests indicate that the addition of slag increase the fluidity, reduce the water demand, shrinkage and expansion, compared to the mortar, containing ten percent (10%) of Silica Fume only. The images of pastes obtained by SEM (scanning electron microscopy), are indicated an improvement of the microstructure of the paste with a large amount of slag, which leads to improve durability.  相似文献   

18.
Iraq is facing water shortage problem despite the presence of the Tigris and Euphrates Rivers. In this research, long rainfall trends up to the year 2099 were studied in Sulaimani city northeast Iraq to give an idea about future prospects. The medium high (A2) and medium low B2 scenarios have been used for purpose of this study as they are more likely than others scenarios, that beside the fact that no climate modeling canter has performed GCM (global climate model) simulations for more than a few emissions scenarios (HadCM3 has only these two scenarios) otherwise pattern scaling can be used for generating different scenarios which entail a huge uncertainty. The results indicate that the average annual rainfall shows a significant downward trend for both A2 and B2 scenarios. In addition, winter projects increase/decrease in the daily rainfall statistics of wet days, the spring season show very slight drop and no change for both scenarios. However, both summer and autumn shows a significant reduction in maximum rainfall value especially in 2080s while the other statistics remain nearly the same. The extremes events are to decrease slightly in 2080s with highest decrease associated with A2 scenario. This is due to the fact that rainfall under scenario A2 is more significant than under scenario B2. The return period of a certain rainfall will increase in the future when a present storm of 20 year could occur once every 43 year in the 2080s. An increase in the frequency of extreme rainfall depends on several factors such as the return period, season of the year, the period considered as well as the emission scenario used.  相似文献   

19.
Solid waste management is a serious problem over the world. Therefore, reduction, re-use and recycling of waste have become major issues in recent days. Gypsum waste plasterboard is considered one example of these waste materials. This study evaluates the use of recycled bassanite, which is derived from gypsum waste plasterboard, to enhance the performance of two types of cohesion-less soil. Recycled bassanite was utilized as a stabilizing agent to improve both compressive and splitting strengths of the tested soil. The effect of bassanite content, soil type, water content and curing time were investigated to explore the behavior of treated soil with recycled bassanite. Test results showed that increase of bassanite content is associated with increase in optimal moisture content, while no significant increase in the dry unit weight was observed. Both compressive and splitting tensile strengths enhanced with the additives of recycled bassanite. The increase of bassanite content had a more significant effect on the compressive strength compared with the effect on tensile strength. The use of recycled bassanite to enhance the strength of sandy soil had a more significant effect compared with silty soil. The effect of curing time on the strength of treated samples was more significant in early curing ages compared with late curing ages. The strength decreased significantly in case of stabilized samples prepared with water content at the wet-side of the compaction curve. However, insignificant decrease in the strength of the stabilized sample was detected with moisture content at the dry-side of compaction curve. This research meets the challenges of our society to reduce the quantities of gypsum wastes, producing useful material from waste materials that will help to a sustainable society.  相似文献   

20.
Energy is one of the most important resources in the economy of developing countries. Jordan depends mainly on imported oil and gas at international prices. This creates a heavy burden upon Jordanian national economy, which is reflected in the same time on other sectors of the Jordanian society. The ever increasing fuel prices make it very necessary to look for new renewable energy resources. Jordan as a developing country with its fast growing urban development and construction projects will be studied. It is worthy to study the dynamic relationship between end user, fuel and comfort in the residential sector. Energy is a chronic problem in Jordan, due to lack of non renewable energy resources, the end consumer is influenced by this fact, in achieving his basic energy needs. This study tries to shed light on the fuel poverty line, definitions and parameters of fuel poverty. And to study what has been done in this regard on both international and local level. No studies have been identified in Jordan which, explore the problem of fuel poverty, especially after the vast and recent increase in fuel prices internationally and locally. This study will follow theoretical and field survey to understand the relationship between comfort, energy and building fabric. Method will depend mainly on field survey and statistical data, and necessary measurements, questionnaires will be adopted when necessary to explore comfort levels related to fuel consumption. Summary and recommendations will be concerned with how thermal comfort could be achieved within the ranges of fuel accessibility, building fabric, minimum pollution and cost.  相似文献   

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