Urte Radvilaite, Á. Ramírez-Gómez, A. Jaras, R. Kačianauskas, D. Rusakevicius
{"title":"Low-resolution spherical harmonics models in application to quasi-quadric particle shapes","authors":"Urte Radvilaite, Á. Ramírez-Gómez, A. Jaras, R. Kačianauskas, D. Rusakevicius","doi":"10.3846/2029882X.2016.1268073","DOIUrl":"https://doi.org/10.3846/2029882X.2016.1268073","url":null,"abstract":"In this paper a numerical analysis was performed developing low-resolution spherical harmonics (LRSH) models in order to describe particle shapes. The potential of LRSH, limited by the expansion degree L ≤ 3, to describe quasi-regular particle shapes was explored. The term “quasi” is used hereafter to indicate the monomeric, almost regular shaped, particle described by a single continuous function. This approach reflects the shape of a major part of soil minerals. It was shown, that even the simplest case of the suggested low-resolution harmonics technique with L = 1 showed sufficient accuracy. The main drawback of the suggested approach was that the low-resolution harmonics yield particle shapes with nearly sharp angles, therefore, enhanced analysis of local surface curvatures becomes necessary. An application using quasi-ellipsoidal particles is enclosed.","PeriodicalId":11839,"journal":{"name":"Engineering Structures and Technologies","volume":"8 1","pages":"131-142"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3846/2029882X.2016.1268073","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69990143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Production of lightweight concrete from waste tire rubber crumb","authors":"J. Akinyele, R. W. Salim, W. Kupolati","doi":"10.3846/2029882X.2016.1209727","DOIUrl":"https://doi.org/10.3846/2029882X.2016.1209727","url":null,"abstract":"AbstractA lot of research has proposed the use of alternative materials in concrete, one of such material that has gained a lot of attention is the waste tire rubber. In this research, rubber crumb was used to partially replace fine aggregate in concrete at 0, 4, 8, 12, and 16% and represented as M0, M4, M8, M12, and M16, respectively. Sieve analysis was carried out on the rubber crumb and sand, while slump, compressive and tensile test were carried out on the concrete samples. The sieve analysis revealed that both the fine aggregate and rubber crumb are poorly graded. The slump test showed that the concrete losses it consistency as more rubber crumb was added. The 28 days compressive strength showed that there was a general reduction in strength. The work concluded that rubber crumb can be used to replace fine aggregate up to 16%, in lightweight concrete.","PeriodicalId":11839,"journal":{"name":"Engineering Structures and Technologies","volume":"8 1","pages":"108-116"},"PeriodicalIF":0.0,"publicationDate":"2016-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3846/2029882X.2016.1209727","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69989877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Bekkouche, T. Benouaz, M. Hamdani, M. K. Cherier, M. Yaiche, N. Benamrane
{"title":"Modelling and experiment of buildings thermo-aeraulic behavior according to the level-compactness in Saharan climate conditions","authors":"S. Bekkouche, T. Benouaz, M. Hamdani, M. K. Cherier, M. Yaiche, N. Benamrane","doi":"10.3846/2029882X.2016.1211492","DOIUrl":"https://doi.org/10.3846/2029882X.2016.1211492","url":null,"abstract":"AbstractA large number of studies of building energy simulation neglect the humidity, or well represented, with a very simplified method. It is for this reason that we have developed a new approach to the description and modelling of multizone buildings in Saharan climate. The concept of the form factor and index compactness “quotient of external walls area and volume of the building” are two of the key elements for analyzing the building geometry. We can introduce it’s as validation tools in some cases.In this paper, governing equations of physical phenomena allow to build a model of the thermo-aeraulic behavior. The primary objective is the validation of numerical results able to determine the humidity and temperature in a multizone space. The calculated results were compared with firstly, experimental values, and secondly with simulated results using TRNSYS software. We check if the results change radically for an invariable compactness index.The comparison shows that the found results are to some exte...","PeriodicalId":11839,"journal":{"name":"Engineering Structures and Technologies","volume":"8 1","pages":"117-130"},"PeriodicalIF":0.0,"publicationDate":"2016-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3846/2029882X.2016.1211492","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69989892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Andrej Mudrov, G. Šaučiuvėnas, A. Šapalas, I. Talvik
{"title":"Plastic capacity of bolted RHS flange-plate joints under axial tension","authors":"Andrej Mudrov, G. Šaučiuvėnas, A. Šapalas, I. Talvik","doi":"10.3846/2029882X.2016.1216806","DOIUrl":"https://doi.org/10.3846/2029882X.2016.1216806","url":null,"abstract":"AbstractThis article considers the calculation of load-bearing capacity of flange-plate joints with bolts along two sides of rectangular hollow sections (RHS) under axial tension. It provides a review and comparison of various calculation methodologies for establishing the load-bearing capacity of RHS flange-plate joints, such as suggested in EN 1993-1-8:2005 and STR 2.05.08:2005 as well as those proposed in different countries and by other authors. Common design principles and derived results for load-bearing capacity of flange-plate joints have been analysed and compared. Following the numerical modelling, which has been done using ANSYS Workbench finite element program, the derived results for load-bearing capacity have been compared with analytical load-bearing capacity results for flange-plate joints of the same structure. The analysis has focused on one type of flange-plate joints with bolts – both preloaded and non-preloaded – along two opposite sides of the tube, with the flange thickness of 15 mm...","PeriodicalId":11839,"journal":{"name":"Engineering Structures and Technologies","volume":"8 1","pages":"85-93"},"PeriodicalIF":0.0,"publicationDate":"2016-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3846/2029882X.2016.1216806","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69989942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The impact of chain extender on the properties of polyurethane foam based on rapeseed oil polyol obtained via chemo–enzymatic route","authors":"A. Kairytė, S. Vaitkus, G. Balčiūnas","doi":"10.3846/2029882X.2016.1209726","DOIUrl":"https://doi.org/10.3846/2029882X.2016.1209726","url":null,"abstract":"AbstractPresently, researches regarding green chemistry are conducted due to its significance for the mitigation of environmental problems, particularly those related to carbon dioxide emissions in relation to global warming and the usage of fossil feedstocks not only for energy generation but also for materials production. The study examines the impact of bio-products such as corn starch, rapeseed glycerin as well as petroleum based propylene glycol as bifunctional and trifunctional chain extenders on physical-mechanical properties of polyurethane foam from rapeseed oil polyol derived via chemo-enzymatic route. The obtained foams were characterized using European and international methodologies for determination of density, compressive strength perpendicular and parallel to foaming directions, thermal conductivity, long-term water absorption after 28 days of immersion, closed cell content and cell size. Foams containing (5–25) pphp of corn starch display significantly lower values in density and compress...","PeriodicalId":11839,"journal":{"name":"Engineering Structures and Technologies","volume":"8 1","pages":"101-107"},"PeriodicalIF":0.0,"publicationDate":"2016-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3846/2029882X.2016.1209726","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69989838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Numerical investigation of the elastic-plastic linear hardening stress-strain state of the frame element cross-section","authors":"A. Grigusevičius, G. Blaževičius","doi":"10.3846/2029882X.2016.1217796","DOIUrl":"https://doi.org/10.3846/2029882X.2016.1217796","url":null,"abstract":"AbstractThe aim of this paper is to present a solution algorithm for determining the frame element crosssection carrying capacity, defined by combined effect of bending moment and axial force. The distributions of stresses and strains inside a cross-section made of linearly hardening material are analysed. General nonlinear stress-strain dependencies are composed. All relations are formed for rectangular cross-section for all possible cases of combinations of axial force and bending moment. To this end, five different stress-strain states are investigated and four limit axial force values are defined in the present research. The nonlinear problem is solved in MATLAB mathematical software environment. Stress-strain states in the cross-sections are investigated in detail and graphically analysed for two numerical experiments.","PeriodicalId":11839,"journal":{"name":"Engineering Structures and Technologies","volume":"80 1","pages":"94-100"},"PeriodicalIF":0.0,"publicationDate":"2016-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3846/2029882X.2016.1217796","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69989958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Review of the sustainable built environment in 1998–2015","authors":"I. Ubarte, O. Kapliński","doi":"10.3846/2029882X.2016.1189363","DOIUrl":"https://doi.org/10.3846/2029882X.2016.1189363","url":null,"abstract":"A city is a complex physical and social phenomenon that is under constant development and undergoes quantitative and qualitative changes. The welfare of the whole society depends on the sustainability of the built environment. The article presents a review of the literature on the sustainable built environment, which was made on the basis of the Thomson Reuters Web of Science Core Collection database. The analysed articles were published between 1998 and 2015. The analysis of the number of publications was made according to years of publication, countries, research areas and the Web of Science categories. 31 article and review document type were selected for a detailed analysis by three key Web of Science categories: environmental science, environmental studies, and construction and building technology.","PeriodicalId":11839,"journal":{"name":"Engineering Structures and Technologies","volume":"40 1","pages":"41-51"},"PeriodicalIF":0.0,"publicationDate":"2016-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3846/2029882X.2016.1189363","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69989765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An exact solution for the resource-constrained construction scheduling problem","authors":"B. Sroka, E. Radziszewska-Zielina","doi":"10.3846/2029882X.2016.1196916","DOIUrl":"https://doi.org/10.3846/2029882X.2016.1196916","url":null,"abstract":"AbstractReduced time and, by the same token, the cost of the project is a crucial factor in contemporary construction. This article presents a method for the exact optimisation of a resource-constrained scheduling problem. Based on the Critical Path Method, graph theory and linear programming, an algorithm was developed and the FROPT program was written in Matlab to minimise the execution time of the task. By using the newly-created program, sample networks were calculated and the results were compared with results obtained by using the MS Project scheduling program (using approximation algorithm). The execution time obtained by using FROPT were on average 10% shorter than those obtained using MS Project. In selected cases the improvement in execution time reached 25%. A deterministic approach to the problem may shorten planned project times and bring financial benefits. Due to the exponential complexity of the algorithm, it is most useful in solving small or highly coherent networks. The algorithm and pr...","PeriodicalId":11839,"journal":{"name":"Engineering Structures and Technologies","volume":"8 1","pages":"71-78"},"PeriodicalIF":0.0,"publicationDate":"2016-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3846/2029882X.2016.1196916","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69989776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Output-only modal identification of tensegrity structures","authors":"M. Attig, M. Abdelghani, N. Kahla","doi":"10.3846/2029882X.2016.1175323","DOIUrl":"https://doi.org/10.3846/2029882X.2016.1175323","url":null,"abstract":"Tensegrity systems are a special class of spatial reticulated structures that are composed of struts in compression and cables in tension. In this paper, the performance of stochastic subspace algorithms for modal identification of complex tensegrity systems is investigated. A sub-class algorithm of the Stochastic Subspace Identification family: the Balanced Realization Algorithm is investigated for modal identification of a tripod simplex structure and a Geiger dome. The presented algorithm is combined with a stabilization diagram with combined criteria (frequency, damping and mode shapes). It is shown that although the studied structures present closely spaced modes, the Balanced Realization Algorithm performs well and guarantees separation between closely-spaced natural frequencies. Modal identification results are validated through comparisons of the correlations (empirical vs. model based) showing effectiveness of the proposed methodology.","PeriodicalId":11839,"journal":{"name":"Engineering Structures and Technologies","volume":"17 1","pages":"52-64"},"PeriodicalIF":0.0,"publicationDate":"2016-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3846/2029882X.2016.1175323","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69990164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Tamošiūnas, Romas Girkontas, A. Savickas, Š. Skuodis, L. Míča
{"title":"Experimental investigation of clay-straw building finishing layer under different drying conditions","authors":"T. Tamošiūnas, Romas Girkontas, A. Savickas, Š. Skuodis, L. Míča","doi":"10.3846/2029882X.2016.1188736","DOIUrl":"https://doi.org/10.3846/2029882X.2016.1188736","url":null,"abstract":"AbstractThis manuscript represents investigation of six different clay mixtures under variable drying conditions, namely: bright yellow clay (typical for Lithuania), brown clay (Lithuania Sergėnai district), mixture of different clays, white Spanish clay, clay mass which is resistant for thermal coldness (with synthetic cardigan) and Lithuanian coarse clay with granite additives. Drying process was provided imitating natural drying process and fast drying in drying oven at 110 C°. The main idea of this study – imitate clay and clay-straw buildings drying process and to determine which of used clay types had smallest volumetric and linear deformations. Volumetric and linear deformations for clay-straw buildings is one of the most important factors evaluating cracking in this type of buildings. To reach this purpose six tiles of different clay types were used. Before drying stage water content, plasticity, and liquid limits index, respectively was determined for all types of clay. All clay tiles volumetric ...","PeriodicalId":11839,"journal":{"name":"Engineering Structures and Technologies","volume":"8 1","pages":"65-70"},"PeriodicalIF":0.0,"publicationDate":"2016-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3846/2029882X.2016.1188736","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69990220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}