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Implementation of Topology Optimization on Building Design-Study Case
Get PDFStructural Optimization, in general, can be interpreted as “the point” where the required structural performance meets the minimal usage of resources and other constraints. The limited material resources, which have concerned researchers and professionals over the last decades, should not affect the quality and the performance a structure must reach. Topology Optimization is a Finite Element based Method, which basically consists in distributing the material in a given volume or in a design domain, so this will lead to designing the structural element that is excepted to satisfying the boundary conditions, achieves the best performance under given solicitations in respect to some design criterion. This paper will briefly present the concept of one of the most successful Optimization Methods ESO/BESO (Evolutionary Structural Optimization/Bi-directional Evolutionary Structural Optimization), its provision of the optimum shape of the structures, reaching the target volume under certain conditions, by adding and taking off elements in the 3D Finite Element Model used as the design domain, illustrated with a short practical example
Unitized Curtain Walls Installation and Some Health and Safety Aspects
Get PDFThis paper discusses good practices and industry experience in the safe installation of unitized curtain walls. An overview of the relevant standards and regulations is presented. Sequence of the installation works and health and safety strategies, methods and appropriate equipment are described and analysed. A reference to the project construction program of works some required preconditions for the facade installation to commence and provisions by the main contractor are discussed. The recommendations and guidance for the Health and Safety planning, provided in this paper, are aimed specifically at unitized curtain walls. The analysis of the discussed aspects is aided by project examples mainly from the United Kingdom, where the unitized curtain wall industry is on the rise and considered well developed
Relationship Between Core Compressive Strength and UPV Values for Different Core Slenderness of High Strength Concrete Beam
Get PDFThe compressive strength of core concrete is affected by many parameters and one of them is the strength of the concrete, which affects the strength of the core compressive strength. This is achieved by using correction factors present in several standards such as ASTM C 42/C 42M-04, but this standard was not considered for high and very high strength concrete (HSC). In this study, a beam of (1x 4x 0.2) m constructed with 100 MPa target strength for core samples. Four different core diameters (25-50-75-100) mm and for each diameter different core length-diameter ratios(λ=l/d) (2-1.75-1.5-1.0) were extracted from the beam for assessing the strength in both casting directions. The relationship between the strength of concrete with respect to reference samples and different cores size with different slenderness ratio, length to diameter (λ) were investigated. The Ultrasonic Pulse Velocity (UPV) was conducted for all samples and the relationship between UPV and strength of cores were determined. The results showed that the core strength was increased with the decrease of slenderness ratio. Core samples correction factors to predict the strength of standard cylinder for HSC beam are different from normal strength concrete (NSC) and they have ranged between 1.0 and 1.12 for beam. Relationship between core compressive strength and UPV values are established
A New Ultrasonic Immersion Technique for the Evaluation of Damage Induced Anisotropy in Composite Materials
Get PDFWe present a theoretical and experimental approach for the characterization of the damage induced anisotropy superimposed to the constitutive anisotropy of fiber-reinforced composite materials.
The proposed theoretical model has been developed in the framework of the Continuum Damage Mechanics theory and allows for determining a tensorial damage measure based on the change of the elastic moduli of the composite material. Moreover, the model is general since it is applicable independently of the fibers reinforcement nature, of the presence of cracks, interlaminar voids and delamination, of the geometry of this cracks, and from of failure mechanisms of the composite materials.
We perform damage experiments by employing an innovative goniometric device designed and built at our laboratory (Laboratorio “M. Salvati”), and aimed at the mechanical characterization of materials. In particular, by rotating the sample into a water tank, we measure the ultrasonic “natural” velocities of the undamaged composite material along suitable propagation directions. This allow us for classifying the degree of symmetry of the material and for determining the elastic constants, also in highly anisotropic materials. Then we measure the ultrasonic velocities of the artificially damaged composite and we determine again the elastic moduli. The comparison between the elastic moduli of the damaged and the undamaged composite allows us for the characterization of the anisotropic tensorial damage measure
Cracks Width in The Middle of the Beam for Beams of Self-Compacting Concrete On the Long Term Process
Get PDFDevelopment trends for high rise constructions, modern skyscrapers indicate that building such constructions with normal concretes and low consistency is impossible, therefore there is a need for concrete with high processes because of great amount of reinforcement in cross-section of concrete elements. Solution for such construction is self-compacting concrete because of its ability to fill good formworks without compaction and vibration. Considering this fact, researches for cracks, mechanical characteristics of concrete and deformations have been conducted worldwide. In this line, we conducted an experimental research to determine the cracks on beams of self-compacting concrete and compared it with theoretical results on the middle of beam on long term process
Degradation of Concrete Structures
Get PDFConcrete has been the most useful material of construction in the recent centuries. It is a mixture, the properties of which change over time. In the residential buildings or infrastructure there have been used various forms of concrete. As a very useful material in the construction, concrete is the element that faces extreme environmental conditions. During the service, the quality of designed concrete can be improved by continuous contact with water as in the case of reservoirs, concrete foundations, etc . But the concrete also can worsen over time due to physical and chemical agents. Consequently, the structures are destroyed when they become unsafe. Degradation of concrete structures has become a crucial matter during the last 20-30 years. Some economically developed countries spend more on repairing and maintenance of structures. As a result, these countries appreciate the longevity of the building rather than the initial cost of its construction.
The aim of this paper is to simplify the destruction schemes of concrete materials from atmospheric agents. As a result it is made an approach to the main phenomen that misbehave with concrete and the way it behaves different from the conditions in which it is located. It is concluded to achieve a long life for concrete, special care should be taken during its preparation and should be maken an intelligent choice as to its constituent materials and their reports
The analysis of Performance and Capacity at a Roundabout with metering signals
Get PDFThis paper aims to describe a method for the analyzing of capacity and performance of roundabout operating with metering signals. The use of metering signals is a found as a measure to avoid the need of a fully signalized intersection, when the low capacity conditions are observed during peak demand flow periods. Roundabout metering signals are often installed on selected roundabout approaches and used on a part time basis, since they are required, when heavy demand conditions occur during peak periods. These metering signals are used normally for alleviating the excessive delay and queues, due to the gaps created in the circulating stream. The basic principles of the operation of roundabout metering signals shall be explained. This paper shall present some analysis results, when operating with metering signals. A case study for some crucial roundabouts in Albania, shall be part of the results and conclusions must be considered to reevaluate the need, when to use metering signals, or not, at the existing congested roundabouts
Analyzing Transport Problems in Tirana on a Sound Scientific System Base
Get PDFThe globalization process taking place recent years has significantly increased the need for mobility. Due to the urban population growth and urbanization, the role of transportation engineering in daily life has mainly increased accompanied by the challenges featuring it. Of importance is the mobility on urban areas, considering the socio-economic and environmental effects. Furthermore in developing countries to such situations contribute the weak enforcement of traffic rules and regulations.
This study illustrate, analyze and provides new methodologies on optimizing traffic congestion in the capital of Albania, Tirana.
Focusing on the road network and public transportation impacts on mobility, the research seeks to outline new strategic solutions for the rapid developing capital, oriented toward society wealth as follows; i) The investigation and illustration of the strengths, weakness and improvements that could be implemented on road network and reorganization inside the urban area of the capital is of first call. ii) As the main motorized transportation mode, reorientation and coordination of public transport system directly affect the socio-economic behavior and smoother traffic flow. iii) The lack of coherent data concerning traffic information system in problematic bottlenecks directly affect traffic management in those zones. In this context, implementation of different techniques for data gathering and application of intelligent transportation system in particular areas like CBD, improves the management of the congestion. Beside, reassessment of the existing and implementation of new parking areas due to future requirements, efficiently smoothers unpredicted congestion situations. iv) Last but not list, the establishment of a framework for actions for the road network and public transportation systems of Tirana results in provision of successive recommendations and analysis. Moreover it shall evaluate the relationship and impact that and public transportation system have on each other and their effect to socio-economic development and environmental issues of the capital
Urban Shape and Energy Performance: Evaluation of The Typical Urban Structures of Prague
Get PDFEuropean cities had been developed historically as compact and dense structures, where the specific urban microclimate was achieved through the arrangement of the units of the urban pattern. The energy flows, such as transportation energy and the heating or cooling energy, were reduced. With the further development of the cities, the various urban morphologies came to place and the city energy demands grew. One of the ways of reduction of such demand is the creation of compact urban pattern, which is exposed to the maximum of solar radiation and potentially may reduce the heating demands of the buildings. The energy, which is received by building, is defined by its shape and orientation and the compacity depends on its geometrical properties, such as surface to volume ratio and the plot coverage. Within the study the various urban morphologies of Prague are tested in order to find the most energy efficient ones. The urban structures are selected according to their geometrical shape and include the urban blocks with different proportions, perimeters and site coverage ratio, dense medieval streets and minimalistic buildings of the socialist period. The computer simulation and analysis were performed using the models extracted from the virtual Google Earth model of Prague. During the process of evaluation of samples the relation between the urban morphology and such parameters as plot coverage, surface to volume ratio and the incident solar radiation was established and potentially higher energy efficient structures were indicated
Stereotomy, Sustainable Construction and Didactics. Case study: a new Museum for Matera, European Capital of Culture 2019
Get PDFThe paper describes the students’ works, which included posters and physical models, were the partial outcomes of the current 3rd year design studio, led by Prof Giuseppe Fallacara and taught with the support of Maurizio Barberio and Micaela Colella, both Ph.D. students at the Polytechnic of Bari. The text illustrate an experimental teaching/learning approach which Giuseppe tested during the design studio. This approach was inspired by the concepts of ‘Experiential Learning’ and ‘Flipped Classroom’, consisting in a series of “cooperative classes”, where tutors and students interacted and discussed in an absolute spirit of intellectual equality. The goal was to simulate the activity of a large architecture practice, involved in the design of a public building, which generally requires the contribution of a large number of architects and designers. The students were given a brief for a new museum and multipurpose centre in Matera, Italy, which was recently nominated European Capital of Culture 2019. They had to deliver a design proposal, a rapid prototyped model and a short video