Life cycle analysis of a steel building

The present study tries to couple structural optimization problems for building frames, with that of energy efficiency optimization. The objective function of the problem takes into account the following parameters: heat capacity, wall and window insulation pro-file, window sizes, losses due to ventilation, boiler and air conditioning system sizing, sizing of steel cross-sections as well as parameters related to the life cycle of the building. Modeling is based on acceptable from national and European regulations procedures. Optimization is solved us-ing evolutionary algorithms. The optimization problem is implemented on a steel building (10x15 m), in Chania, Greece. This is a first attempt to combine Life Cycle Cost and Optimization with classical Structural Optimization for steel structures. Depending on the requirements from the users of the building further evaluation using building energy management system (BEMS) for the intelligent op-eration and management of heating, ventilation and air-conditioning (HVAC) may be performed

Life Cycle Assessment of a Steel-Framed Residential Building

One of the most widely acknowledged policies, which is also strongly promoted by legislation and government officials globally, is sustainable development. Since the introduction of the term and the development of its content, the movement for sustainable development has been accepted by all business sectors as a set of principles that have to be incorporated into standard practice. Particularly in the case of business sectors such as construction that have been identified as the largest consumers of raw materials and energy there has been considerable pressure to optimize processes in terms of sustainability, with particular emphasis on the environmental impact caused. Steel structures constitute a construction technology which holds significant potential in terms of sustainability. The purpose of the current research is to quantify this potential by calculating the environmental impact caused throughout the life cycle of a steel-framed residential building. A life cycle assessment is conducted, taking into account issues such as raw material acquisition, construction and waste management. The results obtained are used to draw conclusions regarding the application of the life cycle assessment methodology to steel buildings and the environmental data required. Furthermore, observations regarding the quantification of the environmental impact caused by the steel-framed residential building and the identification of the most environmentally damaging processes in regard to the life cycle of the building are also made

Environmental Impact Assessment of the Life Cycle of a Timber Building

Timber construction offers a number of advantages in terms of sustainability in comparison with other construction technologies. This can partly be attributed to the fact that structural timber products often require less processing for their manufacturing compared to other construction products and their sustainability is therefore relatively increased. As a result, structures such as timber buildings are associated with increased sustainability potential and are therefore selected as sustainable solutions for the construction of housing, commercial or other types of building projects. The current research, described in this paper, is aimed at the quantification of the environmental impact caused by the construction of timber buildings. A case study is used as the basis for the calculations which take into account the whole life cycle of the timber building examined. A life cycle assessment is conducted and the environmental impact assessment results are calculated according to the Eco-Indicator 99 methodology. The interpretation of the results leads to conclusions regarding the level and type of environmental impact caused by the life cycle of timber building projects

Innovative and sustainable use of stream water to suppress fires in protected areas: overview of the streams-2-suppress-fires project

Establishing protected areas to maintain biodiversity is a priority worldwide. Protected areas can have minimal management practices that can lead to the intensive accumulation of fire fuel. Fires are major threats for all protected areas that cause irreversible damages to them or impacts that last for decades or even centuries. The impending climate change impacts will increase the potential of large fires even in regions with minimal fires in the past. The emphasis of this project is in the Black Sea region with six pilot areas in six different countries. The first action involves the establishment of a Neighborhood Network regarding fire suppression around the region. The network includes institutions that are responsible for mitigating forest fires and managing protected areas from the Black Sea region. Another important action taken is to understand the fire behavior and locating the areas with the greatest fire risk. When considering fire suppression it is essential to know the available water resources (stream water). Since fires occur during the summer, the runoff and stream flow during this period needs to be accurately predicted. Based on the fire behavior and water resources data, the number, dimensions of the reservoirs required to suppress forest fires will be estimated for the pilot areas. Finally, specialized software will provide the optimal locations of the reservoirs and the best routes for the fire vehicles to reach the reservoirs. Overall the use of innovative mechanisms will lead to the more cost-effective management that will allow the sustainable development and protection of natural protected areas

Numerical and experimental investigation of the behavior of extended end-plate connections in steel structures

It is well known that one of the most popular methods of connecting members in structural steel work is the bolted end-plate connection. Bolted end-plates are simple in their use and construction. But they are extremely complex in term of analysis and behavior since the connection behavior significantly affects the structural frame response and therefore it has to be included to the global analysis and the design of frame. The present paper deals with the structural behavior of full-scale stiffened and un-stiffened cantilever connections of typical I sections. The connection between the extended end-plate to the column flange is achieved by means of high strength bolts in each case. In order to obtain experimentally the actual tension force induced within each bolt, strain gauges were installed inside each one of the top bolts. Thus, the connection behavior is characterized by the tension force in the bolt, the extended end-plate behavior, the moment-rotation relation and the beam and column strains. Thereby, it is important to predict the global behavior of column-beam connections by means of their geometrical and mechanical properties. The experimental test results are compared to those obtained by means of a numerical approach based on the finite element method and is coupled to the theory of non-smooth mechanics. All the arising non-linearities in the connection are described through a non-monotone multi-valued reaction-displacement law. Thus, the problem is formulated as a hemivariational inequality leading to a sub-stationarity problem of the potential or the complementary energy of the connection. This simulation problem is solved by applying a non-convex non-smooth optimization algorithm. The comparison of the results of the experimental testing program with the numerical simulation proves the effectiveness of the proposed numerical method

Tightening and loosening torque of M253M bolts: Experimental and analytical investigation

The present paper deals with the study of the installation behavior of high-strength bolts under friction. For this purpose an experimental program was conducted to evaluate the energy of these bolts that is dissipated due to tightening and loosening. The total number of tested specimens was 100 bolts furnished to the requirements of AASHTO specification M253M. The turn-of-nut tightening method is applied experimentally to evaluate the pretension and the torque for tightening and loosening of bolts. It is mentioned that a number of 56 bolts has 76 mm length while the rest is of 152 mm. The experimental preloading and the lost torque that overcomes friction are compared with the respective analytical values. It is confirmed that the K-nut factor is affected by the type of lubricant and the length of the bolt. Additionally, most of torque is going to overcome friction. The percentage of tightening and loosening torque for both the analytical and the experimental cases is very close

The burden of the rheumatic diseases in the general adult population of Greece: the ESORDIG study

OBJECTIVE: To estimate the burden of rheumatic diseases in terms of disability and health-care utilization in the Greek general adult population. METHODS: The study was conducted on the total adult population of seven communities (8547 subjects), as well as on 2100 out of 5686 randomly selected subjects in an additional two communities. Rheumatologists visited the participants at their homes to assess the prevalence of six morbidity indicators concerning disability and health-care utilization associated with rheumatic diseases or other major disease groups. RESULTS: The participation rate in the study was 82.1%. The prevalence of chronic health problems, long-term disability, short-term disability, physician office visits and prescription or non-prescription drug use due to rheumatic diseases in the total target adult population was 14.3, 4.3, 2.9, 2.8, 7.2 and 2.0%, respectively. Compared with all other major disease groups, rheumatic diseases were the most common cause of chronic health problems (38.7%), long-term disability (47.2%), short-term disability (26.2%) and physician office visits (20.5%), while they ranked second for the use of prescription (24.0%) or non-prescription drugs (17.7%). Rheumatic diseases were the main cause of morbidity in five out of six indicators in subjects aged \u3c or =65 yr. Logistic regression analysis revealed an association of female gender, age \u3e or =45 yr and obesity with almost all morbidity indicators related to rheumatic diseases. CONCLUSION: These findings suggest that rheumatic diseases constitute a major public health problem and should be considered in planning undergraduate and postgraduate medical education, research and health-care services

Unilateral contact effects in the structural response of beam-to-column connections

One of the most usual choices for the connection between the different structural members in steel structures is the bolted connection. The later provide a high level of deformation capacity for the whole structure and a level of stiffness comparable to that of fully welded connections. Top and seated angle with double web angle bolted connections are primarily used for beam-to-column joints. The most important factor for the structural response of beam-tocolumn connections is the rotational stiffness because it affects the behavior of the overall structural steel frame. For this purpose, many experimental tests have been recently conducted to obtain moment-rotation curves. Considering the moment-rotation curves obtained from experimental tests, a simplified analytical model has been suggested to predict the behavior of the connection by fitting techniques. The aim of the present paper is, from one side, the development of a moment-rotation curve for bolted top and seat angle connection with double web angle by means of a proposed theoretical model whose validity checked by comparison with experimental data, and from the other side, the determination of the appearing prying forces in the bolts by means of a simplified and reliable model