Unconventional Construction Research Articles

A heuristic approach of modelling developing countries' construction sector uncertainties to improve the building environment

The building environment is predominated almost everywhere in developing countries by fuzzy and unconventional mechanisms, which forms the so-called “informal sector.” The implementation of projects by the owners themselves, small and medium-sized enterprises, in this environment requires severe cost control and time delivery. The construction process in such a complex area is subject to labour fluctuations, productivity variability, difficulties in logistic supply, poor management, use of unsuitable methods, instability of financial means, and therefore delays in the payment of accounts by the contracting authorities. The factors mentioned above are source of major discrepancies between the forecast costs, quality, and deadlines and those obtained at the end of the project. This explains the losses in the execution phase and the prejudices suffered by the main actors in the unconventional construction industry at all levels. By comparing this specific construction sector with the standards, specific uncertainties emerge at several levels of understanding and execution, which, for each task, are the variabilities in quantity, performance, and qualification of workers; the quality and cost fluctuations among supplying networks of materials; the availability and/or inadequacy of equipment used; and the improvised managerial and financial mechanisms. This study, based on matrix modelling of the components of the construction site, leads to implementation of a heuristic approach for assessing those construction costs and delays uncertainties. We proposed analytic formulations of uncertainties that are computed every iteration of possible scenarios. By adapting and applying an iterative (TABU Search), a heuristic algorithm for minimising costs and lead times, it is possible to combine virtually all the possible choices for the different variables in order to anticipate the impact and guide the decision-maker towards the scenario with the least uncertainty and a good reliability of occurrence. Considering the complex parameters of this site of “informal” construction, the model aims to enable stakeholders in the construction sector to incorporate uncertainties into their forecasts before taking decisions not only to reduce or decrease financial losses but also to increase their credibility and ultimately improve this common practice of sustainable construction.

Perception of Spatial Legibility and Its Association with Human Mobility Patterns: An Empirical Assessment of the Historical Districts in Rasht, Iran.

Achieving legibility within the context of historical districts has become a controversial problem due to their widespread growth and unconventional constructions within, which has led to inconsistencies in the urban context system, and a decrease in the level of urban sociability. This paper aims to provide an empirical assessment towards facilitating the perception of spatial legibility and its association with human mobility patterns. To this end, a novel mix method was developed in order to comprehend the association between spatial legibility and human mobility patterns using Space Syntax, cognitive sketch maps, and time-lapse photography. The results revealed that there is a significant association between spatial legibility and human mobility patterns, such that the incorporation of objective and subjective factors affecting legibility, including highly integrated morphological characteristics along with the saliency of landmarks featuring historical values, can lead to increased human mobility patterns in terms of use frequency. Accordingly, this research aids urban planners and designers in recognizing how to deal with historical districts in order to foster the sociability of these areas and create a lively and socially sustainable urban environment.

Development of Concrete Incorporating Recycled Aggregates, Hydrated Lime and Natural Volcanic Pozzolan

Recycling of construction and demolition waste is a central point of discussion throughout the world. The application of recycled concrete as partial replacement of mineral aggregates in concrete mixes is one of the alternatives in the reduction of pollution and savings in carbon emissions. The combined influence of the recycled crushed concrete, lime, and natural pozzolana on the mechanical and sustainable properties of concrete materials is firstly proposed in this study. In this research, unconventional construction materials are employed to produce concrete: the recycled crushed concrete is used as coarse aggregate, while lime and natural pozzolana are used as a partial replacement for cement. Substitutions of 10%, 20%, 50% of gravel are made with recycled aggregates, and 2%, 5%, 10% of cement with lime and natural pozzolan. Tests on the fresh and hardened properties, destructive (compressive strength) and non-destructive tests (sclerometer rebound and ultrasound) of mixtures are carried out. It is shown that the use of recycled materials can provide an increase in compressive strength of up to 34% with respect to conventional concrete. Life cycle cost and sustainability assessments indicate that concrete materials incorporating recycled aggregate possess good economic and environmental impacts.

Standing out with the progressive

In this paper we demonstrate on the basis of diachronic and synchronic data from a variety of languages that progressives are particularly liable to be used for the expression of extravagance. We define extravagant language use as a signaling mechanism that consists in the exploitation of an unconventional construction in a given context as a way for speakers to indicate that there is something non-canonical about the situation that they are reporting. Novel constructions naturally lend themselves to such extravagant exploitation, since they are by definition to a certain extent unconventional. This is why, as we will demonstrate, the English, Dutch and French progressives were notably often recruited in extravagant contexts at the onset of their development. However, our synchronic data reveal that Present-day English, Dutch and French progressives continue to be used for extravagant purposes, which suggests that there is something inherent about progressive aspect that makes it liable to such expressive usage. This is confirmed by data from other, typologically diverse languages. We offer a cognitive-semantic analysis in terms of epistemic contingency in order to account for this intrinsic association of progressive aspect and extravagance across languages. Our analysis thus reveals that extravagance is not a transient property of emerging progressives, but that, instead, the semantics of these constructions makes them particularly liable to be recruited for extravagant purposes. It also demonstrates that in order to analyze the range of uses of progressive constructions in a unified fashion, we need to look beyond the temporal import of these constructions.

EL “POLICUBO” COMO HERRAMIENTA DIDÁCTICA PARA FAVORECER EL PROCESO DE ENSEÑANZA-APRENDIZAJE DE LA CONSTRUCCIÓN INDUSTRIALIZADA

La asignatura Construcciones II “A” de la Facultad de Arquitectura y Urbanismo de la Universidad Nacional del Nordeste aborda la problemática del diseño de sistemas constructivos no convencionales: prefabricación no integral, prefabricación integral y la aplicación de sistemas alternativos (“Ballon Frame” y “Steel Frame”) y contenedores metálicos. El objetivo de este trabajo consiste en analizar el conjunto de viviendas llamado “Kubuswoningen”, localizado en Rotterdam, Holanda y sus posibles aplicaciones en el desarrollo proyectos creativos para utilizar la idea como disparador de la motivación de los estudiantes, estimulándolos en el proceso de diseño, y analizar también los principios geométricos constructivos del “policubo”, que permiten reconocer nuevas formas de responder a la demanda habitacional a la vez que se priorizan los espacios urbanos, recurriendo a la industrialización como herramienta constructiva. La metodología de análisis es de carácter descriptivo, teniendo como base el estudio de obras diseñadas a partir del policubo. Basados en dicho análisis, vemos que la utilización de una modulación puede generar trabajos innovadores en el desarrollo de proyectos de construcción industrializada, explorar nuevas formas de construir y de considerar al hábitat humano, de forma tal que responda a las necesidades humanas y ambientales para fomentar su difusión y desarrollo local.

Environmental Sustainability by Bulk Utilization of Fly Ash and GBFS as Road Subbase Materials

AbstractThe underutilization of fly ash, in contrast with its generation, and scarcity of natural aggregates paved the way to unconventional construction approaches, thereby ensuring environmental ...

Experimental characterization of the narrow channel Hall thruster

A miniature Hall thruster was developed in the Aerospace Plasma Laboratory (APL), Technion, designed to operate at low voltages and mass flow rates. The so-called narrow channel Hall thruster (NCHT) represents a compromise between exhaust velocity and operating power and is of an unconventional construction. The thruster proportions were selected to maintain sufficient gas density in low mass flow rates, resulting in a very narrow and short channel compared to the classical design. A 3 cm NCHT prototype was constructed with a ratio of channel width to mid diameter of 1:30. Initial data from the thruster operation show that at a mass flow rate of 0.38 mg s−1 and power of ≈15 W the thruster achieves a thrust level of about 1 mN. The thruster performance was characterized using both direct thrust measurements and ion beam diagnostics using a retarding potential analyzer.

Underground MRT in Kuala Lumpur – The Inevitable Urban Transit Solution

The traffic congestion in Kuala Lumpur and the high demand for urban space would inevitably lead to an underground transit system. The underground works will be posed with all the constraints and challenges in both design and construction that is unique to Kuala Lumpur’s geology, land use and social-economic structure. The successfully completed underground section of the Sg. Buloh to Kajang (SBK), Klang Valley Mass Rapid Transit (KVMRT) Project between Semantan and Maluri was based on a design and build contract by MMC Gamuda Joint Venture. This paper presents the engineering challenges related to deep excavation and tunnelling in the different geology encountered along the SBK line which include but not limited to the topics highlighted hereafter. The design of deep excavation, temporary retaining systems and other associated works for stations and its performance in Kenny Hill and Kuala Lumpur Limestone. The tunnelling works connecting all the underground stations including the innovative variable density tunnel boring machine, the risk management process, building damage assessment/protection and monitoring particularly to verify the performance of unconventional construction sequence. This paper also make reference to the efforts made to develop the human resource in order to meet the tight construction program. The successful completion of the project is only possible with the dedication and commitment of the client, the management and the support of the many dedicated staff who had laboured tirelessly to complete the project on time and in a safe manner. The valiant effort and cooperation of various parties are gratefully acknowledged without which the subject matter of this lecture would not have been possible.

The Use of an Unconventional Construction Material for Affordable Housing in India

The Use of an Unconventional Construction Material for Affordable Housing in India

The railway superstructure monitoring in bratislava tunnel no. 1 – section of ballastless track and its transition areas

The requirements for the quality of the railway track with emphasis on its long service life, low maintenance costs and the required parameters of the track geometry have led railway infrastructure manager on the territory of the Slovak Republic – Zeleznice Slovenskej republiky (ZSR) – to modernize or to realize reconstructions of railway lines on the appropriate track sections with the application of the unconventional construction of the railway superstructure (ballastless track). The Department of Railway Engineering and Track Management currently performs the monitoring of two sections with the application of ballastless track construction. This paper is aimed to the monitoring of the ballastless track section and presents the results obtained so far in one of the monitored sections in the Bratislava tunnel No. 1.

Toward 21St-Century Korean Hanoks

Very recently, the South Korean architectural field has seen a rising trend to reinterpret the traditional hanok, meaning Korean-style house. While this presents an interesting diversion from the housing market dominated by high-rise apartments, there is a lack of consensus in determining the scope and definition of hanoks. This is because of many experiments with the features of the hanok, such as inclusion of new material, construction techniques, and even radically new spatial organizations. This article explores and analyzes the effectiveness of four different approaches of reinterpreting hanoks: apartment hanoks, urban hanoks, rural experimentations, and contemporary versions. At one end of the spectrum, there is the recent integration of a hanok’s features in high-rise apartments otherwise considered modern. Then I move on to discuss examples of urban hanoks built since the start of the industrialization era in the 1920s and afterwards. Urban hanoks are detached houses, most of which show a stylistic preference toward wooden hanoks of the elite literati. The third approach is rural experimentations that involve the development of an unconventional construction method by both architects and non-architects. Finally, this paper turns to reinterpretations of the hanok by architects trained in contemporary architecture. Although each approach differs in the degree of integrating historical hanok features, some commonalities, such as low floor area ratio and the organic integration of an open courtyard, can be detected among the successful cases.

On the borrowability of subject pronoun constructions in Turkish–Dutch contact

Turkish spoken in the Netherlands (NL-Turkish) sounds different in comparison to Turkish spoken in Turkey (TR-Turkish) due to Dutch influence. In addition to borrowed Dutch words/phrases, Dutch influence on NL-Turkish is also observed through literally translated constructions. This study investigates the Dutch influence on NL-Turkish constructions with subject pronouns. Analyses of NL-Turkish and TR-Turkish spoken corpora do not reveal any significant differences in terms of subject pronoun frequency. However, qualitative analysis of the data reveals some unconventional cases of subject pronoun use in NL-Turkish. In these cases, subject pronouns do not lead to unconventionality on their own but as parts of larger constructions that are copied from Dutch as chunks. Following the principles of usage-based approaches, these unconventional constructions are further analyzed in terms of their level of schematicity and flexibility.

Unconventional construction of DNA codes: Group Homomorphism

One of the key problems in DNA computation is the design of large and reliable codes. Due to the biological and chemical restrictions, DNA codes need to satisfy certain constraints. Here, we provide an algebraic procedure to construct DNA codes by using homomorphism of groups. The construction procedure is used to determine mutation.

Neural Correlates of the Perception for Novel Objects

Perception of novel objects is of enormous importance in our lives. People have to perceive or understand novel objects when seeing an original painting, admiring an unconventional construction, and using an inventive device. However, very little is known about neural mechanisms underlying the perception for novel objects. Perception of novel objects relies on the integration of unusual features of novel objects in order to identify what such objects are. In the present study, functional Magnetic Resonance Imaging (MRI) was employed to investigate neural correlates of perception of novel objects. The neuroimaging data on participants engaged in novel object viewing versus ordinary object viewing revealed that perception of novel objects involves significant activation in the left precuneus (Brodmann area 7) and the right visual cortex. The results suggest that the left precuneus is associated with the integration of unusual features of novel objects, while the right visual cortex is sensitive to the detection of such features. Our findings highlight the left precuneus as a crucial component of the neural circuitry underlying perception of novel objects.

Building constructions of stone cladded roofs in contemporary architecture

Stone roof coverings have existed for hundreds of years now, but their application in contemporary representative architecture is quite different than it was in former times, and accordingly the underlying constructional details are much more complicated. The main role of the roof in today's architecture is to emphasize the abstract building volume and its homogeneity. The design (visual appearance) has priority over constructional considerations, while at the same time requirements for thermal insulation and the watertight buildup of the building envelope are rising. This is a big challenge for the design of the constructional details, since traditional methods do not apply anymore: almost all of the water gets under this exterior cladding where a completely waterproof underlayer is needed. Therefore a new type of constructions is borne. In this article I try to present innovative constructional alternatives for stone cladded roofs and try to define guidelines for their planning. These alternatives were created and refined based on analysis of historical and contemporary examples, the examination of the specific conditions and requirements that affect cladded roofs, their expected performance over their life-span, the difficulties that arise under construction and my work experience. I created seven groups, according to the method for fixing the individual stone elements, since this is the detail that most affects the buildup of the underlying structure. A new approach is needed with these unconventional constructions, with a much more detailed inventory of every little feature of the building in question. But since these features vary violently with the architectural conception the exact constructional solutions are usually unique as well.

Thermal behaviour of an earth-sheltered autonomous building – The Brighton Earthship

The benefits of reducing the thermal effect of global warming and structural damage by severe storms have renewed interest and drives to heavyweight constructions. One type of heavyweight construction using earth-sheltered construction known as an ‘Earthship’ has been developed and pioneered by US architect Michael Reynolds and recently introduced to the UK. The ‘Earthship’ takes on the concept of an ‘independent vessel’, which operates on a self-sufficient basis and is constructed largely from recycled and reclaimed materials. Although there are up to 3000 globally, only two Earthships have been built in the UK – one in Brighton and one in Scotland. The publicity resulting from the planning approval granted in April 2007 for the construction of sixteen domestic Earthships at the seafront of Brighton have raised public awareness to this type of unconventional construction. A key feature of the Earthship design is the use of a thermal store, which acts as a seasonal heat buffer to absorb heat in the summer and to release heat in the winter, to regulate the room temperature. This paper reports on the initial findings of a long-term study on the thermal behaviour of the thermal store and its effect to the indoor environment. It introduces the design and construction principles of the Earthship and outlines the process and equipment used in the thermal monitoring of the building. Indicative results from the analyses of the data collected at the early stage are reported and discussed. Initial findings have demonstrated the effectiveness of the thermal charging and discharging of the earth-rammed thermal mass, which appeared to moderate the extreme external temperatures.

EC1-2: Mechanical Efficiency and Losses of Internal Combustion Engines with Cylinder Axes Parallel to Drive Shaft Axis(EC: Engines and Engine Components,General Session Papers)

Barrel engines are characterized by unconventional construction feature: cylinder axes are parallel to drive shaft axis. The rotation of the central power shaft is created from the reciprocating motion of the pistons with the use of different types of mechanisms, including wobble plate, swash plate or cam disc. Due to complex internal motion their kinematics and dynamics is completely different than that of crankshaft engine. Barrel engines are expected to have a potential to compete with currently used power units, especially in aircraft applications. The paper reviews and compares all classified types of barrel engines with conventional crankshaft engine in terms of kinematics: mechanical losses and mechanicals efficiency. Advanced computations were made for each mechanism to derive formulas describing three-dimensional movements of barrel engines' parts. Comparison of mechanisms parameters was made with the use of MatLab software. Computations methodology for mathematical description of all mechanisms' kinematics is presented as well as the results of mechanical losses and efficiency comparison. Wobble plate mechanism blocked by gear has been identified as the most promising for further analysis and research.

A Medium Power Electrostatically Focused Multiple-Beam Klystron

This paper presents data on a new device, a 7-beam, electrostatically focused klystron oscillator/amplifier with planned output of 2-kW continuous wave (CW) at 5.8 GHz for an RF-excited ion thruster. An abridged presentation of this paper was given at the International Vacuum Electronics Conference/International Vacuum Electron Sources Conference (IVEC/IVESC) 2006 Conference in Monterey, CA. Advantages over conventional magnetic focusing are discussed. A tube was constructed that exhibited expected performance. It produced about 500 W with three beams at saturation and was operated as both an oscillator and an amplifier. DC beam transmission was 99% but degraded rapidly at saturation. We discuss ways to mitigate this problem. Cavity gaps were used as focus lenses by applying a dc voltage across them, and this improved overall beam focusing. A technique for splitting cavities without lowering Q is presented. An unconventional construction technology was employed and is described.

Is There Something Wrong With Turkish In The Netherlands?

Turkish spoken in the Netherlands (NL-Turkish) is described as "idiosyncratic", "different" or simply "wrong" by monolingual Turkish speakers in Turkey (TR-Turkish). It is a well-known fact that languages in contact affect each other in various ways (Thomason, 2001). As a result of contact, changes may occur in the linguistic systems of the contact languages. According to Owens (1996), these changes start with the borrowing of multi word unit (construction) structures from the contact language or languages. Based on this observation, this study explores the question if the borrowed structures of Dutch constructions cause NL-Turkish to be identified as unconventional by TR-Turkish speakers. As a case study, unconventional non-finite constructions are analyzed. The results of the analyses reveal structural copying of Dutch constructions in several ways, which causes unconventionality in NL-Turkish.

Design considerations for permanent magnet synchronous motors for flux weakening applications

The required parameter values of a permanent magnet synchronous motor designed for very large power-speed range are determined based on a linear dq model. It is shown that unconventional motor constructions with the d-axis inductance equal to, or bigger than, the q-axis inductance can provide superior torque, power factor and control characteristics. The initial sizing state of a design procedure is described. Analytical equations are developed and used to illustrate the influence of the rotor configuration, electromagnetic loading and air-gap length on the performance of a relatively large range of medium-sized motors. Suggestions regarding the improvement of efficiency, power factor, overload performance and PM protection against permanent demagnetisation are also given. The results of the analytical design procedure have been checked against finite element computations and experimental data.