Showing papers in "American Journal of Civil Engineering and Architecture in 2013"
TL;DR: In this article, the authors investigate whether using sustainable construction methods save money by reducing a buildings carbon output and running costs, and find that there is an opinion within the industry that sustainability means increased cost and complicated build ability.
Abstract: Sustainability has become the most important issue concerning the construction industry in the 21st century. The objectives of this paper were: to establish if there is an opinion within the industry that sustainability means increased cost; and to investigate whether using sustainable construction methods save money by reducing a buildings carbon output and running costs. Following the literature survey, a questionnaire survey has been carried out to canvas opinions within the industry. Furthermore, comparison of a traditionally built structure (the original college) against a sustainably built one (the structure being built to replace the original building) has been carried out as a case study with respect to the running costs and carbon outputs. The findings revealed that there is an opinion within the industry that sustainability means increased cost and complicated build ability and that using sustainable construction methods save money by reducing a buildings carbon output and running costs. This paper will benefit clients and developers as they can see how incorporating sustainability into new buildings will enable big savings on utility and maintenance costs once the building is operational.
45 citations
TL;DR: In this paper, waste polyethylene and polyvinyl chloride (PVC) as the sort of polymer is used to investigate the potential prospects to enhance asphalt mixture properties and to check the design criteria of asphalt mixture using this two modifier at optimum binder content.
Abstract: Since the forefront invention of Polyethylene and Polyvinyl chloride (PVC), it has been spasmodically used in every possible purpose which is biologically non-degradable and has a blimp environmental problem leading astringent environmental impact. Nevertheless, for such property of sustainability the polyethylene and PVC have been reused in the field of transportation engineering for enhancing the property of asphalt binder, since for having a desirable binding property. At the same time the recycling of waste polyethylene and PVC can save disposal sites and reduce the amount of inert drawn from quarries. In this investigation, waste polyethylene and PVC as the sort of polymer is used to investigate the potential prospects to enhance asphalt mixture properties and to check the design criteria of asphalt mixture using this two modifier at optimum binder content. The investigation concentrated on the test of modified binder properties and Marshall mix design was used, first to determine the optimum binder content and then further to test the modified mixture properties. The tests include the determination of unit weight, stability, flow and voids characteristics. Some of the measured properties of asphalt mixture with the modifier used in this study were within the acceptable recommended limits. On the basis of experimental results, it is concluded that the asphalt mixtures with waste polyethylene modifier up to 10% and waste PVC modifier up to 7.5% can be used for flexible pavement construction in a warmer region from the standpoint of stability, stiffness and voids characteristics.
44 citations
TL;DR: In this article, the results show that with water-cement ratio (0.46), core compressive strength increase by 3.9% to 5.6% by replacing 20% of the cement content with ceramic dust, and no significant change in flexural strength and split-tensile strength when compared to the conventional concrete.
Abstract: Ceramic dust is produced as waste from ceramic bricks, roof and floor tiles and stoneware waste industries. Concrete (M35) was made by replacing % (up to 30%) of cement (OPC 53) grade with ceramic dust (passing 75µm) shows good workability, compressive strength, split-tensile strength, flexural strength and elastic modulus. In this experimental investigation, concrete specimens were tested at different age for different mechanical properties. The results show that with water – cement ratio (0.46), core compressive strength increase by 3.9% to 5.6% by replacing 20% cement content with ceramic dust. It was observed that no significant change in flexural strength and split-tensile strength when compared to the conventional concrete.
34 citations
TL;DR: Predictive model of compressive strength for plain concrete confined with Ferrocement has been developed by using MATLAB Artificial Neural Network (ANN) simulation and showed that compressed strength estimated by ANN predictive model are very close to the experimental results than existing theoretical models.
Abstract: This paper is an extension of the work published in year 2010 in which compressive strength of plain concrete confined with Ferrocement was estimated using mathematical models and compared with 55 experimental results. In this paper, predictive model of compressive strength for plain concrete confined with Ferrocement has been developed by using MATLAB Artificial Neural Network (ANN) simulation. Out of 55, 19 experimental results are selected for training of multilayer feed forward neural network. Comparative analysis of the results showed that compressive strength estimated by ANN predictive model are very close to the experimental results than existing theoretical models.
24 citations
TL;DR: It was found that nearly all drivers of either gender and any age were prone to at least moderate levels of anger, though specifics about driver commutes, such as length and type of commute, did significantly influence likelihood of experiencing anger.
Abstract: Road rage is accepted as a legitimate danger to the safe, effective, and efficient operation of the transportation system, it is important to understand its prevalence, and the characteristics of drivers that can be used to predict potential for it. By distributing a modified version of the Deffenbacher Driving Anger Scale to a wide variety of drivers and compiling the data collected from that, it was possible to determine just how common driving anger and road rage truly were. It was found that nearly all drivers of either gender and any age were prone to at least moderate levels of anger, though specifics about driver commutes, such as length and type of commute, did significantly influence likelihood of experiencing anger. While it is likely impossible to ever eliminate this driving anger entirely, there are measures that can be taken to significantly reduce the frequency of its occurrence. By implementing changes to modern transportation engineering city design and development models, particularly focusing on reducing or reimagining urban sprawl, improving traffic flow in city driving, and implementing more strict anti-road rage laws which discourage drivers from acting on their driving anger, it is possible to eliminate some of the factors most likely to induce driving anger and road rage, thereby reducing the frequency of road rage occurrence within the transportation system as a whole.
20 citations
TL;DR: In this article, the effects of aggregate types on physic-mechanical properties of concrete were investigated and it was proved that aggregate type has a severe effect on physicmechanic properties of the concrete.
Abstract: Both coarse aggregates and fine aggregates are the main constituents of concrete because they not only give the body to the concrete, it also have a significant effect on the fresh concrete based on aggregate’s shape, size, texture, grading and crushing type. Moreover it is proved that aggregate’s types has the severe effect on physic-mechanical properties of concrete as aggregate covered almost 70 to 80 percent of the total volume of concrete. This paper investigates the effects on properties of concrete due to types of crushed aggregates alone. To observe the effects of crushed aggregates sharply, all other components like water cement ratio kept constant for each type and two types of crushed aggregates were used. ‘Impact Crushed’ and ‘Vertically Shafted’ aggregates type have been used to prepare five different groups of concrete blocks and these five groups have different water-cement (w/c) ratio. Source of these two aggregates, density and water absorption also kept constant to identify the effects on properties of concrete only for crushing type. Finally after 1 week and after 4 weeks slump values (consistency of the concrete) and compressive strength were measured without mixing any admixture or superplasticiser to the concrete. Compressive strength difference for all groups at 1 week and 4 weeks also analysed at the end of the study.
19 citations
TL;DR: In this paper, a life cycle energy and cost analysis of the school building design, predicting the impact on the operational cost of the building as a result of the addition of photovoltaic panels is presented.
Abstract: This paper is concerned with assessing the building’s the energy efficiency and qualities of a modular design for the education industry, in order assess the long economic benefits. The research includes a life-cycle energy and cost analysis of the school building design, predicting the impact on the operational cost of the building as a result of the addition of photovoltaic panels. The paper also includes a comparative study between the ECO Modular Solutions building, and a current standard prefabricated school building, quantifying the savings in CO2 emissions and savings in cost.
18 citations
TL;DR: In this paper, the authors investigated the water supply system and sanitation facilities in urban slums of Bangladesh and found that majority slum households use tube well water for drinking but significant numbers of them are found to use open latrine for defecation.
Abstract: Slum population has been increasing in Bangladesh over the last three decades along with the growth and expansion of cities and towns. But slum facilities are very much unsatisfactory for them due to the lack of proper water supply and sanitation system. Therefore, the major portion of the households use unsafe latrine and deposit their children's excreta into road side drain and open places, which pollutes water sources, groundwater and the general environment. As a result, majority of the population in Bangladesh suffer from different kinds of water and excreta-borne diseases that aggravate their poverty situations. So, the main objective and essential goal of the study is to investigate the water supply system and sanitation facilities in urban slums of Bangladesh. During the study period, data has been collected by questionnaire survey from each slum households (15 slums and 5324 households in RCC). However, the hygienic practice has been found to be significantly low among the all households in slums although they have enough knowledge about it. The study has showed that majority slum households use tube well water for drinking but significant numbers of them are found to use open latrine for defecation. Normally, pit and water seal latrines are found which are partially hygienic. These may cause ground water contamination depending on the soil characteristics and distance between the water sources and latrines. The open disposal of excreta pollutes the nearby water bodies, canals and drains causing severe environmental pollution. Many motivational work and idea marketing from government and NGO sides help to improve their awareness level.
15 citations
TL;DR: In this article, a ten point (0-9) condition rating system is proposed for obtaining present condition of reinforced concrete (RC) structures based on the measured values of concrete cover, carbonation depth and chloride concentration at rebar depth through in-situ tests.
Abstract: Evaluating present condition of reinforced concrete (RC) structures is necessary for planning future maintenance and estimating residual service life of structures. A ten point (0-9) condition rating system is proposed for obtaining present condition of RC structures based on the measured values of concrete cover, carbonation depth and chloride concentration at rebar depth through in-situ tests. Proposed condition rating has been related to maintenance, inspection and replacement priorities. A model similar to Tutti’s model (1982) (Figure 1) has been developed and presented in this article to predict remaining service life of deteriorated structure, by evaluating present condition of RC structures.
14 citations
TL;DR: This paper is giving a simple and cheapest solution to create virtual 3D campus of any educational institute by using simple photographs based on Close range Photogrammetry and will describe the introduction, methodology, advantages, drawbacks and limitations of this method.
Abstract: Virtual 3D modeling is a very important and hot topic for researchers of Geomatics. Many scientists are working in this direction. All over the world, so many educational institutes are available with its own campus. Campus is the land on which Institute; College or University buildings are situated. In the modern digital era, the demand of 3D Campus is increasing. Virtual 3D model of campus gives a good and photo-realistic appearance. In Geomatics market, So many image based techniques are available for 3D modeling. Photogrammetry and Laser scanning are the main Geomatics techniques. Satellite Photogrammetry and Aerial Photogrammetry is not easy to use by every person, because the images are not easily available for everybody. Due to this a new approach is possible to make virtual 3D Campus. Close Range Photogrammetry is very easy to use. Images are easy to obtain by any handheld digital camera. Cost and Time is main key issue for this. In this paper, we are giving a simple and cheapest solution to create virtual 3D campus of any educational institute by using simple photographs based on Close range Photogrammetry. In this study, we used simple digital images obtained by a Hand held digital camera. This paper will describe the introduction, methodology, advantages, drawbacks and limitations of this method. In this study, we used the study area, Campus of Department of Civil Engineering, Indian Institute of Technology, Roorkee, (Uttrakhand), India. From this study, we find out the height and length of building of Civil Engineering department. The result of this study is also within the permissible limit and acceptable. It is a significance study for 3D modeling by using Close Range Photogrammetry. This 3D campus model can be exported in various other formats for various applications. These 3D models can be exported to Google Earth also. These 3D campus models can also be published on the website of that Institute or University.
14 citations
TL;DR: In this paper, the physical and chemical characteristics of decomposed solid waste and leachate collected from Matuail landfill sites were investigated, and the average concentrations of Fe, Cu, and Ni in leachates samples collected from treated pond were found to be 19.11 mg/l, 0.71mg/l and 2.5mg/L respectively exceeding Bangladesh standards.
Abstract: Rapid urbanization of Dhaka city has created immense pressure on its urban services including solid waste disposal. Both city corporations (Dhaka North, DNCC and Dhaka South, DSCC) have been facing tremendous problem to maintain sustainable waste management over the last few decades. At present, the DNCC and DSCC dump 68% of the total sold waste to the sanitary landfill site at Matuail. Decomposed solid waste is a potential source of heavy metals and toxic chemicals that pollute the soil as well as the surrounding water body. For environmental sustainability, it is now essential to reduce the load of decomposed solid waste at landfill site through the conversion of waste into re-usable product. Proper characterization of solid wastes is pre-requisite for efficient management and solid waste stabilization. In this paper, it is therefore aimed to investigate the physical and chemical characteristics of decomposed solid waste and leachate collected from Matuail landfill sites. The average concentrations of Fe, Cu, and Ni in leachate samples collected from treated pond were found to be 19.11mg/l, 0.71mg/l, and 2.5mg/l respectively exceeding Bangladesh standards. The presence of heavy metals in decomposed solid waste was also found to be significant. In order to reduce the scale of pollution it is recommended to stabilize solid waste to use it as a construction material. Physical properties that were analyzed in this study will also be helpful for selecting stabilizing additive for perfect stabilization.
TL;DR: In this paper, the authors demonstrate the analysis of the pavement transverse surface profile that could be used to identify the layer responsible for the permanent deformation in a 300 meter section on National Highway (N-5) exhibiting severe rutting.
Abstract: Rutting is one of the major distresses which cause hydroplaning and structural failures in a flexible pavement. The extent of damage depends upon the load induced and the strength of each pavement layer. Rutting can occur due to the failure of the subgrade, the base or at the wearing surface/ hot mixasphalt (HMA) layer(s).In order to take remedial measures, it is imperative to be cognizant of the contribution of each layer to ascertain the cause of underlying phenomena of rutting. This research study demonstrates the analysis of the pavement transverse surface profile that could be used to identify the layer responsible for the permanent deformation. Transverse surface profiling techniqueis easier, non-destructive, and economicalas compared to traditional methods of coring and trenching to examine underlying layers. A 300 meter section on National Highway (N-5) was selected exhibiting severe rutting to perform transverse profile analysis. Results of this study suggest that rutting at the selected site is mainly due to the shear failure of HMA layer. These results were also validated by field trenching on the test section. The study concluded that HMA layer should be removed and replaced with appropriately designed high performance mix specifications.
TL;DR: In this paper, the authors examined the relative importance of socio-economic and land use factors on household daily trips generation rate and household kilometers travelled and developed linear regression models to develop a travel demand forecasting model.
Abstract: Influence of socio-economic and land use factors on households travel behavior are important to develop a travel demand forecasting model. This paper examines the relative importance of these factors on household daily trips generation rate and household kilometers travelled. Linear regression models have been developed in this regard. Data used to develop these models have been collected from household’s survey among different zones of Sylhet City Corporation (SCC) area and other secondary sources. From the model output, it has been found that land use parameters (accessibility and entropy) have significant contribution on trip production, trip attraction and household kilometers travelled along with the socio-economic characteristics of the people living in SCC area. The model framework developed in this paper can help to formulate comprehensive transport and land use policy for the different cities of Bangladesh as well as for other developing countries, particularly those in Asia, which share similar socio-economic characteristics.
TL;DR: In this article, two new configurations of bi-directionally inclined shear connector are proposed to obtain load-deflection response of steel-concrete-steel (SCS) sandwich construction, which combines the advantages of both steel and concrete and finds application in numerous areas such as bridges, protection against impact and blast loads, flooring system etc.
Abstract: Steel-concrete-steel (SCS) sandwich construction combines the advantages of both steel and concrete and finds application in numerous areas such as bridges, protection against impact and blast loads, flooring system etc. Shear connector is a critical component of SCS system. In the present study, two new configurations of bi-directionally inclined shear connector are proposed. Response behaviour of SCS beams with bi-directionally inclined connector is obtained through numerical investigations. Finite element models of SCS beams are generated by using a simplified approach that employs solid, plate and beam elements to represent concrete, cover plates and shear connector respectively. Behaviour of concrete is represented using concrete damaged plasticity model, while steel behaviour is modelled by using bilinear stress-strain curve. Beam is simply supported and is subjected to a central concentrated load. Nonlinear static analysis is carried out to obtain load-deflection response. Numerical model is validated by solving a SCS beam with through-through connectors, which was experimentally investigated in literature. Responses from bi-directionally inclined connectors are compared with that of through-through connectors. Bi-directionally inclined connector is found to be more ductile compared to that of through-through connector, while the load carrying capacity remains same. Parametric study is carried out by varying the cover plate thickness, angle of inclination and diameter of the connector to study their influence on the behaviour of the steel-concrete composite beam.
TL;DR: In this article, the effect of stirrup orientation on flexural response of reinforced concrete (RC) deep beams with two different shear-span-to-depth (a/d) ratios is presented.
Abstract: In this paper, the effect of stirrup orientation on flexural response of reinforced concrete (RC) deep beams with two different shear-span-to-depth (a/d) ratios is presented. For RC beams with the same shear and flexural reinforcements, shear failure is most likely to occur in deep beams rather than in regular beams. Thus, solution for deep beams with shear deficiencies is of great importance. For that purpose a lateral, vertical and inclined stirrup design with two different ‘a/d’ ratios is proposed. A series of tests were carried out in order to demonstrate the effect of proposed design. The test results of proposed lateral stirrup design indicated the increase of load carrying capacity. The present study shows that the ‘a/d’ ratio has more influence on the shear capacity, as ‘a/d’ ratio increases, the shear strength increases in case of short deep beam. The relative effectiveness of lateral (horizontal), vertical and inclined web reinforcement on the load capacity is mainly influenced by the ‘a/d’ ratio. The strength considered for investigation is flexural strength. Beam of size 700mm X 150mm X 150mm for flexure strength. The specimens were water cured for 28 days and tested with 2 point load subsequently.
TL;DR: In this article, the authors focus on the pejorative attitudes that have historically been held against the disabled community and highlight the barriers that the built environment creates, and make recommendations for proper building design and implementation relating to access issues for disabled users and able bodied.
Abstract: The need to reconcile access issues and conservation has become ever more important as legislation has become more demanding of service providers. From October 2004 service providers have had a duty of care to provide and improve access within their buildings. This has come into direct conflict with Conservation Legislation which protects the historic value and significance of listed buildings. The paper focuses on the pejorative attitudes that have historically been held against the disabled community and highlights the barriers that the built environment creates. Research aims were to: visit three listed English heritage buildings of differing age and construction and; investigate the changes taken place as a result of the Disability Discrimination Acts (DDA) ; investigate whether these adaptations satisfy Approved Document M (ADM) and DDA criteria and have improved access for all while still considering and maintaining conservation and historical requirements. With these aims, following the literature review, three case studies were conducted. The findings revealed that although all three buildings were mostly compliant with the requirements of ADM, there was a lack of commitment to improve access continually. The recommendations for proper building design and implementation relating to access issues for disabled users and able bodied are analysed.
TL;DR: In this article, a fuzzy inference system (FIS) was developed to predict the shear strength of reinforced concrete beams using Mamadani method and the regression analysis between the output of the FIS model and the corresponding target, R2 = 0.9969 and 0.9509, respectively.
Abstract: The main objective of the present study is to predict the ultimate shear capacity of reinforced concrete beams no contains web reinforcement. Fuzzy inference system (FIS) was developed to predict the shear strength of these beams using Mamadani method. Fuzzy inference system (FIS) model has been proved to be very effective in predicting the ultimate shear strength of concrete beams without stirrups. The regression analysis between the output of the FIS model and the corresponding target, R2 = 0.9969 and 0.9509 for training and testing data, respectively. Based on FIS results, a parametric analysis was carried out to study the influence of each parameter affecting the shear strength of beams without stirrups and these results are compared with the provisions of ACI-code.
TL;DR: In this article, a comparison of four types of roof (slab and three types of dome) in hot and dry climatic zone of Iran, Esfahan city is presented.
Abstract: As a covering method of buildings` roof, domed roof have mostly been applied in Iran and other countries according to adobe material abundance comparing with timber ones. Furthermore, dome remains in first place in architectural designs due to their favorable thermal performance; so that it has been widely utilized in mosques, shrines, churches, bazaar and schools construction. On this account, the current research studies on the role of shape in roofs energy loss specifically in cold annual period to achieve the optimized form. The paper discusses a comparison to four types of roof (slab and three types of dome) in hot and dry climatic zone of Iran, Esfahan city. The research method is based upon modeling and simulation. It is to find the most efficient form of buildings which can be designed in contemporary architecture of developing countries. The result shows that although the flat shape roof appears in an appropriate thermal performance, there is a meaningful correlation between roofs total volumes and heating load at night, however the result is in need of further investigation.
TL;DR: In this article, a relational database using ACCESS software is developed and is populated with experimental results of 2145 shear critical reinforced concrete beams without web reinforcement using both normal as well as high strength high performance concrete.
Abstract: The shear strength of reinforced concrete members is a function of shear capacity of concrete (Vc), which in turn depends on influencing parameters including concrete compressive strength (f’c), ratio of tension reinforcement (), shear span to depth ratio (a/d), size effect or depth factor (ξ), size of the aggregate in relation to the minimum size of the member (aggregate interlock aspects).Over the last several decades, researchers have tested reinforced concrete beams (without web reinforcement) over a range of variables limited by the breadth and depth of their experimental investigations and on the basis of their experimental results, have proposed empirical equations for predicting the shear capacity of normal and high strength-high performance concrete in reinforced concrete beams. In this paper a relational database using ACCESS software is developed and is populated with experimental results of 2145 shear critical reinforced concrete beams without web reinforcement using both normal as well as high strength –high performance concrete. An evaluation was also conducted to assess the predictive accuracy of shear design equation of Euro Code EC2. The results indicate for beams of normal as well as high strength concrete, the Euro Code EC2 design equation is adequate to accurately predict the shear capacity of reinforced concrete beams over the range of variables considered in this study.
TL;DR: In this article, the development of BIM and how it can contribute to the cold-formed steel (CFS) building industry is examined through the adoption of a qualitative methodology encompassing a literature review, exploratory interviews with industry experts, culminating in a development of e-learning material for the sector.
Abstract: The ability of building information modeling (BIM) to positively impact projects in the AEC through greater collaboration and integration is widely acknowledged. This paper aims to examine the development of BIM and how it can contribute to the cold-formed steel (CFS) building industry. This is achieved through the adoption of a qualitative methodology encompassing a literature review, exploratory interviews with industry experts, culminating in the development of e-learning material for the sector. In doing so, the research team have collaborated with one of the United Kingdom's largest cold-formed steel designer/fabricators. By demonstrating the capabilities of BIM software and providing technical and informative videos in its creation, this project has found two key outcomes. Firstly, to provide invaluable assistance in the transition from traditional processes to a fully collaborative 3D BIM as required by the UK Government under the "Government Construction Strategy" by 2016 in all public sector projects. Secondly, to demonstrate BIM's potential not only within CFS companies, but also within the AEC sector as a whole. As the flexibility, adaptability and interoperability of BIM software is alluded to, the results indicate that the introduction and development of BIM and the underlying ethos suggests that it is a key tool in the development of the industry as a whole.
TL;DR: In this article, the results of a representative sample of LCA studies, most of them published in international journals or in free access research reports, are analyzed and comments the results.
Abstract: In the last years, following the technological progress in wood processing industry and the increased use of wood-based products in construction industry, the scientific community has investigated the environmental performances of wood-base building materials and their substitution potential of energy-intensive material.The article describes and comments the results of a representative sample of LCA studies, most of them published in international journals or in free access research reports. All analyzed LCA studies compare wood, as a building system, with other materials and construction technologies (such as reinforced concrete, steal and masonry); these studies highlight the potential of wood-based building materials to improve the environmental performances of construction industry besides the possible negative aspects related to the wood product manufacturing and the construction process. Some methodological limits are considered comparing LCA results among selected studies, because of the variability of the case studies, the subjectivity of the system boundary definition and the differences between the referenced data sources. However the comparative purpose of this analysis provides an interesting framework of the current research and highlights how timber buildings and wood-based products could still improve their environmental performances during all life cycle stages. Wood, as construction material, could increase its competitiveness in building industry thanks to its environmental performances, starting from its renewable source and its carbon storing potential.
TL;DR: In this article, the authors used ANSYS software to model three models of steel cylindrical reservoirs (with the same height to diameter proportion) containing fluid by applying the finite element method.
Abstract: Steel cylindrical reservoirs had the highest utilization in the field of oil source storage and petrochemical in the recent years due to their significant importance. These types of reservoirs are conventionally made with steady and floating roofs. Long term erosion agents have destructive impacts on dynamic features of these reservoirs. Results of numerical researches demonstrate that the internal corrosion of reservoir walls as a constant dependent to time, which is made due to the connection of fluids and chemical interactions with the internal wall of reservoir causes the corrosion of inside the reservoir wall and reduction in wall stiffness. In this research dynamic behavior of three models of steel cylindrical reservoirs (with the same height to diameter proportion) containing fluid is modeled using ANSYS software by applying the finite element method. In this modeling, features of a cylindrical reservoir containing 0.9 height of liquid is used which its fluid is considered to be incompressible and viscose. First Modal and Harmonic analyses are used to evaluate the natural frequency and formed mode-shapes in the tank-fluid system. These models are compared and verified with the similar and current experimental formulas. Next by applying corrosion on one of the tanks, dynamic features are evaluated using the software. Then some mass is applied in the place of corrosion to the walls of reservoir with proper boundary conditions in several steps, which in each step, the changes in the added mass are considered using the transient analysis and finally the natural frequency is evaluated. This cycle continued until the frequency of reservoir having added mass has equaled to the frequency of corrosion reservoir which this method is called equivalent mass. In the end, the added mass to the reservoir is formulated using mathematical techniques. Based on the analytical results we found that corrosion or long term erosion have remarkable influences on natural frequency, mode-shapes of structures and its vibration.
TL;DR: In this paper, a comparative life cycle analysis (LCA) for green facades with vegetation is presented, and the similarity and differences in the environmental impacts in relation with benefits estimated for two climate types for building energy saving (reduction of electrical energy used for building cooling and heating).
Abstract: Greening the building envelope focusing on green facades with vegetation is a good example of a new construction practice. Plants and partly growing materials in case of green wall systems (GWS) have a number of functions that are beneficial, for example: increasing the biodiversity and ecological value, mitigation of urban heat island effect, outdoor and indoor comfort, insulating properties, improve of air quality and of the social and psychological well-being of city dwellers. This paper discusses a comparative life cycle analysis (LCA) for: a conventional built up brick facade, a facade greened directly, a facade greened indirectly (supported by a steel mesh), a facade covered with a green wall system based on planter boxes and a facade covered with a green wall system based on felt layers. Beside the environmental benefits of the above described greening systems, it is eventually not clear if these systems are sustainable, due to the materials used, maintenance, nutrients and water needed. A LCA is used to analyze the similarity and differences in the environmental impacts in relation with benefits estimated for two climate types for building energy saving (reduction of electrical energy used for building cooling and heating).
TL;DR: In this article, the main feature of sustainability in Iran's contemporary architecture is investigated and what criteria have been applied for its utilization, and what sorts of sustainability related considerations have been taken into account by the architects and building designers.
Abstract: The environmental challenges, the significant effects of architecture, building manufacture technologies and the construction industry have caused the movement towards sustainable architecture to be considered as one of the most important and influential trends in the early years of the 21st century. Sustainable architecture and compliance with environmental features have also been noted in Iran both in theory and practice. However, it seems that in the developing countries, particularly in Iran, the architects’ tendency towards the concept of sustainability possesses some features of its own. Therefore, the foremost questions addressed in this study are: 1-what is the main feature of sustainability in Iran’s contemporary architecture? And what criteria have been applied for its utilization? 2- What sorts of sustainability- related considerations have been taken into account by the architects and building designers? The methodology adopted to investigate these issues is the conduct of case studies, utilizing the compound strategies. The data collection was performed via a library procedure, whereby thirty samples of Iran’s contemporary and post- revolution architecture for which sustainability was considered were selected. The findings of the study reveal that the trend of sustainability in Iran’s contemporary architecture mostly manifests itself in attempts to maximize the usage of solar energy, to choose the optimal direction for a building, the light absorption capabilities, proper ventilation based on the specific climate and weather, and the use of plants in the space.
TL;DR: In this article, the results of a laboratory study on the treatment of a clay soil in the area of the Inhabitant of Algiers by incorporation of various contents of lime are presented.
Abstract: Lime is flexible hydraulics which has the property to improve the soil mechanics characteristics. For the muddy and argillaceous grounds, the traditional interaction between lime and their minerals is noticed immediately. The ground becomes friable and is drained, especially with the quicklime; the mixture can be stored for one short period (a few weeks) without its intrinsic properties not changing. For a good soil stabilization with lime it is necessary to lay out of certain relative data to the soil mechanics properties, like plasticity, granulometry and the water content to evaluate the possibilities for improvement. This work consists at the presentation of the results of a laboratory study on the treatment of a clay soil in the area of the Inhabitant of Algiers by incorporation of various contents extinct lime. For that, physical and mechanical tests such as (unconfined compression test, classification tests of the grounds in 1st place and shear test) were carried out and the results obtained highlight an unquestionable and definitely better improvement of the characteristics geotechnics such as the resistance of compression, resistance of shearing (angle of friction and cohesion).
TL;DR: In this article, a mixed force-displacement method based on the use of the differential equations of both the bar axial deformation and the beam bending is proposed for solving the unknowns in solving the algebraic equations derived by the proposed approach are represented by the integration constants of each mono-axial frame.
Abstract: This paper deals with the solution of statically undetermined plane frames by using a mixed force-displacement method based on the use of the differential equations of both the bar axial deformation and the beam bending. The unknowns in solving the algebraic equations derived by the proposed approach are represented by the integration constants of each mono-axial frame of the structure. The applications examples show that, even if the dimensions of the problem are larger than both cases related to the use of the force and of the displacement methods, the proposed approach does not require post-processing for finding any kinematic and static response quantity. Therefore, this approach can be considered as an alternative to the Finite Element approaches for solving plane multi-axial frames.
TL;DR: In this paper, the behavior of cantilever concrete quay walls placed on the saturated cohesive soil is studied using finite element method in ANSYS Software, where height of the quay wall, soil type, strength and duration of the earthquake on the bending moment against the wall are considered and pressure distributions behind the wall have been investigated.
Abstract: Optimal design of Quay Walls against seismic forces has become a challenge for engineers. For countries that are placed on the earthquake belt, it is very important to investigate the strength and behavior of quay walls against earthquakes. In this study, the behavior of cantilever concrete quay walls placed on the saturated cohesive soil is studied using finite element method in ANSYS Software. Patterns of the interaction between soil and structure prove to be very complicated. On the other hand, with the consideration of the interactions between soil and structure under the seismic forces, the problem will be made much more complicated. In the present study, height of the quay walls, soil type, strength and duration of the earthquake on the Bending moment against the wall are considered and pressure distributions behind the wall have been investigated.