Academic literature on the topic 'Shell Roofs'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Shell Roofs.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Journal articles on the topic "Shell Roofs"
1
Teng, J. G., H. T. Wong, Z. C. Wang, and S. L. Dong. "Steel-Concrete Composite Shell Roofs: Structural Concept and Feasibility." Advances in Structural Engineering 8, no. 3 (July 2005): 287–307. http://dx.doi.org/10.1260/1369433054349105.
Full textAbstract:
This paper describes a new structural system, namely steel-concrete composite shells, for enclosing large spaces and presents test and numerical simulation results to demonstrate its feasibility. These composite shells are formed by pouring concrete on a thin stiffened steel base shell which serves as both the permanent formwork and the tensile steel reinforcement. The thin steel shell, constructed by bolting together open-topped modular units consisting of a base plate with surrounding edge plates, is a steel shell with thin stiffeners in both directions. The new system retains all the benefits of thin concrete shells, but eliminates the need for temporary formwork and minimises the required falsework. In this paper, the background to the development of this new structural system is first given, followed by a description of its structural features. Advantages of this new structural system over existing systems are next discussed. Possible failure modes of the new structural system are also outlined. Finally, a study to demonstrate the feasibility of constructing these shell roofs of large spans with very thin steel sheets and a limited amount of shoring is presented. In this feasibility study, a finite element model was developed for bolted steel arches as a conservative approximation of bolted steel shells, and was verified using results from simple connection tests. Both the connection tests and the verification of the finite element model are given in this paper before presenting the results from the parametric study.
2
Sahoo, Sarmila. "Free Vibration of Laminated Composite Hypar Shell Roofs with Cutouts." Advances in Acoustics and Vibration 2011 (December 25, 2011): 1–13. http://dx.doi.org/10.1155/2011/403684.
Full textAbstract:
Use of laminated composites in civil engineering structural components including shell roofs is increasing day by day due to their light weight, high specific strength, and stiffness properties. In the present paper, laminated composite hypar shell (hyperbolic paraboloidal shells bounded by straight edges) roofs with cutouts are analyzed for their free vibration characteristics using finite element method. An eight-noded curved shell element is used for modeling the shell. Specific numerical problems of earlier investigators are solved to compare their results with the present formulation. A number of problems are further solved where the size of the cutouts and their positions with respect to the shell centre are varied for different edge constraints. The results are furnished in the form of figures and tables. The results are examined thoroughly to arrive at some meaningful conclusions useful to designers.
3
Bakshi, Kaustav, and Dipankar Chakravorty. "Static and Dynamic Characteristics of Composite Conoidal Shell Roofs." Advances in Acoustics and Vibration 2013 (December 3, 2013): 1–9. http://dx.doi.org/10.1155/2013/539817.
Full textAbstract:
A thorough review of the existing literature reflects that forced vibration studies of laminated composite conoidal shells with complicated boundary conditions are missing. Hence, the present paper aims to fill the lacuna. A finite element code utilizing eight-noded doubly curved elements together with modified Sanders’ first approximation theory for thin shells is used to study the forced vibration behavior of moderately thin laminated composite conoidal shells subjected to three different uniformly distributed time-dependent forces. Newmark’s direct time integration method is used to solve the dynamic problem. Results obtained using the present code are compared with the values available in the literature, and a good agreement of the results confirms the accuracy of the proposed code. The transient responses of the laminated shell are studied meticulously for parametric variations like boundary conditions and stacking orders of cross and angle-ply laminates and are compared with bending responses of the shell to conclude on the necessity of the dynamic study.
4
ANCHOR, R. D. "CONCRETE SHELL ROOFS, 1945-1965." Proceedings of the Institution of Civil Engineers - Structures and Buildings 116, no. 3 (August 1996): 381–89. http://dx.doi.org/10.1680/istbu.1996.28749.
Full text
5
Mbakogu, F. C., and M. N. Pavlović. "The prestressing of shell roofs." Engineering Structures 21, no. 1 (January 1999): 16–33. http://dx.doi.org/10.1016/s0141-0296(97)00138-7.
Full text
6
Abramczyk, Jacek. "Transformed Corrugated Shell Units Used as a Material Determining Unconventional Forms of Complex Building Structures." Materials 14, no. 9 (May 5, 2021): 2402. http://dx.doi.org/10.3390/ma14092402.
Full textAbstract:
This article is an insight into interdisciplinary topics in the field of civil engineering, morphology, architecture, mechanics, and computer programming. A novel method for shaping unconventional complex roofs in which regular folded units transformed into various shells are used as a complex substitute material is proposed. The original method’s algorithm for building systems of planes defining diversified polyhedral networks in the three-dimensional space by means of division coefficients of the subsequently determined vertices is presented. The algorithm is based on the proportions between the lengths of the edges of the reference network, the location and shape of the ruled shell units included in the designed complex roof structure, so it is intuitive. The shell units are made up of nominally flat folded sheets transformed effectively into shell forms whose static-strength properties are controlled by geometric quantities characteristic of ruled surfaces. The presented original approach to the shaping of the shell roof structures determining specific complex building forms allows us to go beyond the limitations related to the orthotropic structure of the folded roof sheeting and the shape transformations.
7
Prokopska, Aleksandra, and Jacek Abramczyk. "Responsive Parametric Building Free Forms Determined by Their Elastically Transformed Steel Shell Roofs." Buildings 9, no. 2 (February 14, 2019): 46. http://dx.doi.org/10.3390/buildings9020046.
Full textAbstract:
The article concerns the unconventional architectural forms of buildings roofed with transformed shells made up of thin-walled steel fold sheets, and a parametric description of how they are shaped. Complicated deformations of flanges and webs, as well as the complex static–strength work of the folds in a shell roof, demand the creation of simplified models regarding the parameterization of such shells and their integration with the general forms of the buildings. To obtain favorable results, it was necessary to write computer applications because of both the complicated problems related to the significant limitations of the transformations, as well as the great possibilities of shaping shell roofs by means of directrices of almost free shape and mutual position. The developed procedures enable the prediction of shapes and states of all the folds in the designed shell. They take account of two basic conditions related to these restrictions, which guarantee that the folds encounter little resistance when matching their transformed forms to the roof directrices, and that their initial effort was as low as possible. The developed procedures required solving a number of issues in the fields of architecture, civil engineering, and structures, and are illustrated with an example of shaping one unconventional architectural form. The interdisciplinary study explains a new insight into shaping such forms.
8
Sahoo, Sarmila. "Behaviour and Optimization Aids of Composite Stiffened Hypar Shell Roofs with Cutout under Free Vibration." ISRN Civil Engineering 2012 (June 28, 2012): 1–14. http://dx.doi.org/10.5402/2012/989785.
Full textAbstract:
A scrutiny of the literature reveals that the free vibration characteristics of stiffened composite hypar shell with cutout are missing. So a generalized finite element formulation for the stiffened hyperbolic paraboloidal shells bounded by straight edges (commonly called as hypar shells) is attempted using an eight-noded curved quadratic isoparametric element for shell with a three-noded beam element for stiffener. Numerical problems of earlier investigators are solved as benchmark problems to validate the approach. A number of problems are further solved by varying the size of the cutouts and their positions with respect to the shell centre for different edge constraints. The results are presented in the form of figures and tables. The results are further analysed to suggest guidelines to select optimum size and position of the cutout with respect to shell centre considering the different practical constraints.
9
San, Bingbing, Chen Xu, and Ye Qiu. "Three-Dimensional Aerodynamic Optimization of Single-Layer Reticulated Cylindrical Roofs Subjected to Mean Wind Loads." Advances in Civil Engineering 2019 (August 21, 2019): 1–13. http://dx.doi.org/10.1155/2019/4156319.
Full textAbstract:
This paper presents a procedure to optimize the rise-to-span ratio of single-layer reticulated cylindrical roofs to improve their aerodynamic performance, by coupling the optimization method with computational fluid dynamics (CFD) and finite element analysis (FEA). Four turbulence models (standard k-ε, RNG k-ε, SST k-ω, and RSM) were used to predict the mean wind loads on cylindrical roofs. The simulation results were compared with wind tunnel data, and the RSM turbulence model was employed. The aim of this paper is to determine the best performing rise-to-span ratio of cylindrical roofs based on the gradient algorithm. Two objective functions were considered to minimize the highest mean suction on the roof surface and the maximum response displacement of the single-layer reticulated cylindrical shell subjected to mean wind loads. The results revealed that a cylindrical roof with a rise-to-span ratio (R/S) of 1/6.25 seems to be most effective in attenuating high suctions on the roof surface. In addition, a single-layer reticulated cylindrical shell with R/S = 1/5.5 gives the best performance in reducing the maximum response displacement against wind loads.
10
Abramczyk, Jacek. "Folded Sheets as a Universal Material for Shaping Transformed Shell Roofs." Materials 14, no. 8 (April 19, 2021): 2051. http://dx.doi.org/10.3390/ma14082051.
Full textAbstract:
This article provides a novel insight into specific properties of flat folded sheets transformed elastically into building roof shells. Elastic twist transformations of the sheets resulting from the arrangement of the sheets on two skew roof directrices cause changes in the geometric and mechanical sheet properties of the roof shell sheeting composed of these sheets. Regular smooth-ruled surfaces and their characteristic lines are used in the analysis of changes in the geometric properties. In the analysis of the mechanical changes, the constitutive relations and complex state of stresses are considered. The analysis is carried out on the basis of the results of the experimental tests and FEM computer simulations. They have led to the development of such a method of shaping of the effectively transformed folded covers that ensures the initial effort of each shell fold to be the smallest possible.
Dissertations / Theses on the topic "Shell Roofs"
1
Ostovari, Dailamani Shadi. "Behaviour of cylindrical and doubly-curved shell roofs under earthquake." Thesis, University College London (University of London), 2010. http://discovery.ucl.ac.uk/516142/.
Full textAbstract:
There are indications that thin shells are once again becoming a popular option for roofs covering large column free spaces. Relative to other structural forms there is relatively little analysis of their dynamic response. Especially in seismically active regions, this paucity of analyses could be of considerable significance. This research reports a verification study based upon two independent methods: a finite element solution and a newly developed analytical method. For typical cylindrical shell roofs these methods have been used to determine the spectra of natural vibration modes, displacements, accelerations and stress resultants of the shell under the action of the vertical motions of a selected earthquake. The comparisons showed the FE and analytical results to be in practically excellent agreement. The study of the numbers of modes required for accurate prediction of displacement, acceleration, and stress response for a specific geometry of shell showed that unlike ordinary buildings, in roof shells there is a need to include substantial number of modes for a converged result. Of the limited past investigations on how thin shell roofs respond to earthquakes, attention has been restricted to consideration of just the out-of-plane modes, with the contributions from the in-plane modes usually neglected. The importance of the inclusion of in-plane modes for a cylindrical shell subject to the vertical component of a selected earthquake loading showed that these modes can potentially have a major impact on the predicted levels of in-plane deformation and the associated membrane stresses, and therefore depending on the type of earthquake should be included for reliable estimates of earthquake response. The assessment of the relative importance of the horizontal and vertical components of earthquakes showed that vertical components result in higher accelerations and stresses compared to the horizontal components. In the past investigations of how thin shell roofs respond to earthquakes, attention has been largely restricted to linear analysis, with contributions from pre-loading usually neglected. The independent approaches using finite element solution and a newly developed analytical method indicate that inclusion of self-weight and additional superimposed loading can significantly reduce the predicted natural frequencies. Consequently inclusion of pre-loading is shown to have a major influence on the levels of deformations and the associated membrane stresses. It is concluded that performing a modal analysis in which the effects of pre-loading are ignored could lead to serious underestimation of responses for large roof shells under earthquake loading. Furthermore a nonlinear snap buckling analysis showed that the snap buckling loads are much lower than the classical critical loads in cylindrical roof shell, which suggest a need for a complete nonlinear analysis for the cases of shell with pre-loading close to snap buckling loads. The final section of the present research compares the frequencies and linear responses of a doubly curved shell with a cylindrical shell. The results showed that the frequencies of a doubly curved shell are higher than a cylindrical shell. The increase in the natural frequencies resulted in much lower displacements and stress resultant responses in the doubly curved shell.
2
Bayram, Ayca. "Energy Performance Of Double-skin Facades In Intelligent Office Buildings: A Case Study In Germany." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/107830/index.pdf.
Full textAbstract:
The building industry makes up a considerable fraction of world’
s energy consumption. The adverse effects of a growing energy demand such as depletion in fossil fuel reserves and natural resources hassled the building industry to a search for new technologies that result in less energy consumption together with the maximum utilization of natural resources. Energy- and ecology-conscious European countries incorporated the well-being of occupants while conducting research on innovative technologies. In view of the fact that double-skin faç
ades offer a healthy and comfortable milieu for the occupants and use natural resources hence consume less energy they became a promising invention for all concerns. The analysis of the performance of the double-skin faç
ades and energy consumption is inconclusive at this time. However, based upon thermal performance analysis have been done so far, a double-skin faç
ade perform better and provide some energy reduction, particularly on the heating side cycle, from a standard double glazed unit wall. The aim of this study was to examine the relationship between double-skin faç
ades and building management systems in intelligent office buildings as they relate to energy efficiency issues thus to find out whether or not the integration of these systems into intelligent buildings provides optimization in energy performance and comfort conditions. The building for the case study, which is an intelligent office building incorporating a double-skin faç
ade was selected as one that promises high comfort conditions for the occupants with low energy consumption. The working principles of integrated faç
ade systems, together with their advantages and disadvantages were investigated by means of the case study. It was concluded that due to their high initial costs, these systems offer no real advantages for today. However with the inevitable exhaustion of fossil fuels that is foreseen for the future, these systems would become an innovative solution in terms of energy conservation.
3
Kelley, David Frederick. "Safety and stability in concrete barrel shell roof structures." Thesis, Monterey, California. Naval Postgraduate School, 1991. http://hdl.handle.net/10945/26232.
Full text
4
Lozano, Galant Jose Antonio. "Cylindrical Thin Concrete Shells : Structural Analysis of the Frontón Recoletos roof." Thesis, KTH, Bro- och stålbyggnad, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-36792.
Full text
5
Teixeira, Pedro Wellington Gonçalves do Nascimento. "Projeto e execução de coberturas em casca de concreto com forma de membrana pênsil invertida e seção tipo sanduíche." Universidade de São Paulo, 1999. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-13122017-155101/.
Full textAbstract:
Coberturas em casca de concreto apresentam bom desempenho estrutural, desde que a forma de sua superfície média seja adequada para resistir predominantemente com esforços de membrana ao carregamento atuante. Atualmente, é possível utilizar-se métodos numéricos para determinar a forma mais adequada de uma casca para carregamentos de naturezas diversas e várias condições de apoio, projetando-se cascas com forma livre. Uma das grandes dificuldades para aplicação dessas estruturas consiste em compatibilizar um processo executivo adequado para moldagem de formas livres, que têm características geométricas muito complexas. A utilização de processo executivo de construção tipo sanduíche, com concreto ou argamassa projetados, é vista neste trabalho como uma alternativa para a viabilização dessas estruturas. Propõe-se definir procedimentos para o projeto de cascas com forma livre, utilizando-se recursos computacionais para definição da forma e análise da estrutura, e um método construtivo adequado a esse tipo de estrutura. Apresentam-se os resultados de geração de formas livres com métodos numéricos disponíveis, bem como parâmetros que podem auxiliar na aplicação dessas formas livres em projetos de coberturas em casca, baseados em resultados numéricos de análise dessas estruturas. São descritas as experiências de execução de dois protótipos de cobertura em casca, com aplicação de argamassa em núcleo de material leve, posicionado entre telas de aço moldadas na forma de membranas pênseis invertidas. Apresentam-se os resultados obtidos em prova de carga de um dos protótipos executados, bem como comparações desses resultados com os obtidos em modelos numéricos, comprovando-se o bom desempenho da estrutura, mesmo sendo a seção formada por duas faces finas sem conexão rígida. Acredita-se que o procedimento executivo proposto para moldagem de cascas com forma livre pode, com pequenas melhorias, ser utilizado na execução de estruturas semelhantes, mesmo com dimensões maiores, compondo-se, dessa maneira, um processo tecnológico viável.Concrete shell roofs are very efficient structures when designed to support the loads mainly by membrane forces. Nowadays, there are numerical methods that can be used to determine the suitable shell shape, once it is given the loading and the boundary conditions, with a great variety of these parameters, thus creating the so called free form shells. When applying these shell shapes at practical situations, using conventional concrete construction technology, problems appear because of their very complex geometrical characteristics. Sandwich type construction and shotcrete have been seen in this work as alternatives to solve many construction problems involved with free form shell construction. It is propposed that conceptual design of free form shells, with basis on computational methods, be applied together with a adequate construction method to define a design methodology. Results of the application of numerical methods for shell shape generation are presented, as well as data that can be used when apllying these shell shapes in roof design. Two prototypes were built by applying mortar on ligthweight curved panels fixed between two steel meshs. The results of a loading test performed on one of these prototypes are described and compared with those obtained in a numerical simulation. The prototype proved to be so stiff, beware the fact that the thin faces of the sandwich section did not have rigid shear connections. One believes that there are sufficient data to ensure that the proposed construction method is very suitable to cast free form shell roofs and so it can be used, with few improvements, even on large span structures.
6
Michalov, Patrik. "Administrativní budova." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2020. http://www.nusl.cz/ntk/nusl-410052.
Full textAbstract:
The subject of the master's thesis is elaboration of the complete project design documentation of a administrative building, ready for implementation in the construction phase. The object is divided into four above-ground floors and one underground floor. It is divided into three blocks A, B, K and into three independent functional units. The prevailing part of building is administrative part, which is located in blocks A and B. In the basement there is a compound garage. Part of the building comprises of a service, a café, located and operated on the first floor above ground in block K. The individual blocks have separate entries and are without any mutal limitation to their independent operations. The building has a carrier system designed as a monolithic, reinforced concrete skeleton with two reinforced cores, placed on reinforced concrete feet. Ceramic fittings are slated for filling . The roof structure designed as a single-shell flat roof area, eventually vegetative. The facade is designed as ventilated with cement-bonded particle boards. Within the specialization is the solution of technical equipment, forced ventilation by means of air-conditioning system.
7
Nováček, Filip. "Návrh uskladňovací nádrže." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230600.
Full textAbstract:
The aim of this diploma thesis is to design of storage tank for petroleum. The thesis is divided into two parts. In the first part of the work is focused on introducing the known types of storage tanks, their parts, use and benefits. The thesis also briefly summarized legislation regarding this issue. The second part is the actual design of storage tank. It was the strength calculation tanks according to EN 14 015. It was also a voltage FEM analysis of shell and tank roof. Result of work is a design drawing of the storage tank.
8
Rejnart, Michal. "Statické řešení kostela v Brně." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-372251.
Full textAbstract:
This diploma thesis deals with design of roof structure of the church in Brno Lesná. It is arched shell, which is symmetrical only by one axis. The roof is clamped by bond beam at supports of roof structure, which sits on a reinforced concrete walls, which transfers load to foundations. This structure is checked for the Ultimate Limit State and Service Limit State. Text part of design contains report, where is described structural system and technological proces. The structural design report contains assessment proces of designed structure.
9
Bartolčicová, Alice. "Mateřská škola." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265620.
Full textAbstract:
This thesis describes the design and solution of the object for the education of children of preschool age. It is a newly built kindergarten in the village Želetice, which consists of two classes, each for 20 children. The whole building is divided into several zones - children's departments, communication zone, administrative zone and economic zone.The building is designed as a single-storey brick building and plan corresponds to an L-shaped. Ceiling is made of prestressed panels Spiroll and the roofing is made as single-flat roof.
10
Doležal, Lukáš. "Polyfunkční objekt." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2019. http://www.nusl.cz/ntk/nusl-392253.
Full textAbstract:
The subject of the master’s thesis is the project documentation of building work for multifunctional building. The object has three floors. The structural system of the building is bricked. The roof of the building is flat and the terraces are designed as vegetation and walking. On the mainfloor there are situated commercial spaces, building technical facilities and seven residential units. On the second floor there is space for commercial use and seven residential units and on the last floor there is also space for commercial use and one residential units.
Books on the topic "Shell Roofs"
1
IASS-CSCE International Congress (1992 Canada). Innovative large span structures: IASS-CSCE International Congress 1992 : concept, design, construction = Structures innovatrice de grande portée : IASS-SCGC congrès international 1992. Montreal: The Canadian Society for Civil Engineering, 1992.
Find full text
2
Asia-Pacific, Conference on Shell and Spatial Structures (1996 :. Beijing China). Proceedings of the Asia-Pacific Conference on Shell and Spatial Structures, May 21-25, 1996, Beijing, China. Beijing: China Civil Engineering Society, 1996.
Find full text
3
Chatterjee, Binoy Kumar. Theory and design of concrete shells. London: Chapman and Hall, 1988.
Find full text
4
1910-1997, Candela Félix, and Henn Ursula, eds. Zum Werk von Felix Candela: Die Kunst der leichten Schalen. Köln: R. Müller, 1992.
Find full text
5
Isler, Heinz. Heinz Isler, Schalen: Katalog zur Ausstellung. Stuttgart: K. Krämer, 1986.
Find full text
7
Komptetenzzentrum Typologie & Planung in Architektur (CCTP). Das modulare Bausystem Living Shell: Qualitätsvolle Verdichtung durch Ausbau und Sanierung von Dächern und Fassaden. Zürich: VDF Hochschulverlag AG, 2017.
Find full text
8
Cueto Ruiz-Funes, Juan Ignacio del and Acción Cultural Española (Organization), eds. Félix Candela. Madrid, Spain]: Acción Cultural Española, 2012.
Find full text
9
Universität für Angewandte Kunst Wien. Institut für Architektur, ed. Techo en Mexico: The Mexican roof revisited 2009. Wien: Springer, 2011.
Find full text
10
Garlock, Maria E. Moreyra. Félix Candela: Engineer, builder, structural artist. Princeton, NJ: Princeton University Art Museum, 2008.
Find full textBook chapters on the topic "Shell Roofs"
1
Blaauwendraad, Johan, and Jeroen H. Hoefakker. "Hyperbolic- and Elliptic-Paraboloid Roofs." In Structural Shell Analysis, 107–28. Dordrecht: Springer Netherlands, 2013. http://dx.doi.org/10.1007/978-94-007-6701-0_8.
Full text
2
Farshad, M. "Design of Concrete Cylindrical Shell Roofs." In Design and Analysis of Shell Structures, 63–101. Dordrecht: Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-017-1227-9_5.
Full text
3
Ghosh, Arghya, and Dipankar Chakravorty. "On Progressive Failure Study of Composite Hypar Shell Roofs." In Advances in Structural Engineering, 103–11. New Delhi: Springer India, 2014. http://dx.doi.org/10.1007/978-81-322-2190-6_10.
Full text
4
Pandey, Suman, and Tanmoy Chakraborty. "A Parametric Study of Deflection Behavior of Damaged Composite Conoidal Shell Roofs." In Lecture Notes in Mechanical Engineering, 11–21. Singapore: Springer Singapore, 2022. http://dx.doi.org/10.1007/978-981-16-6738-1_2.
Full text
5
Pandey, Suman, and Dipankar Chakravorty. "Response of Delamination on Static Behaviour of Simply Supported Composite Conoidal Shell Roofs." In Lecture Notes in Civil Engineering, 93–99. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-6389-2_10.
Full text
6
Bakshi, Kaustav, and Dipankar Chakravorty. "First Ply Failure of Laminated Composite Conoidal Shell Roofs Using Geometric Linear and Nonlinear Formulations." In Advances in Structural Engineering, 113–24. New Delhi: Springer India, 2014. http://dx.doi.org/10.1007/978-81-322-2190-6_11.
Full text
7
Blaauwendraad, Johan, and Jeroen H. Hoefakker. "Circular Cylindrical Roof." In Structural Shell Analysis, 83–106. Dordrecht: Springer Netherlands, 2013. http://dx.doi.org/10.1007/978-94-007-6701-0_7.
Full text
8
Jawad, Maan H. "Roof Structures." In Theory and Design of Plate and Shell Structures, 350–68. Boston, MA: Springer US, 1994. http://dx.doi.org/10.1007/978-1-4615-2656-8_13.
Full text
9
Hao, Zhao Xing. "Mechanical Property Analysis of Hyperbolic Paraboloid Shell Roof." In Computational Mechanics ’88, 667–68. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-61381-4_172.
Full text
10
Pohly-Bergstresser, Sibylle. "Der Ogoni-Shell-Komplex: Zur Geschichte einer Grass-Roots-Bewegung." In Afrika Jahrbuch 1995, 35–44. Wiesbaden: VS Verlag für Sozialwissenschaften, 1996. http://dx.doi.org/10.1007/978-3-322-91407-1_5.
Full textConference papers on the topic "Shell Roofs"
1
Dong, Baosheng, Xinwei Zhao, Hongda Chen, Jinheng Luo, Zhixin Chen, Hua Zhang, Guangli Zhang, Lingkang Ji, and Yi Zhang. "Nonlinear Stability Analysis of the Vaulted Roofs With Corrosion Defects of Oil Storage Tank." In ASME 2009 Pressure Vessels and Piping Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/pvp2009-77527.
Full textAbstract:
The vaulted roofs of oil storage tank are usually designed as the shallow spherical shells subjecting to a uniform external pressure, which have been widely observed that these shallow spherical shells undergo various levels of corrosion in their employing conditions. It is important to assess the stability of these local weaken shallow spherical roofs due to corrosion for preventing them from occurring unexpected buckling failure. In this paper, the uniform eroded part of a shallow spherical oil tank vaulted roof is simplified as a shallow spherical shell with elastic supports. Based on the simplification, a general pathway to calculate the critical pressure of eroded shallow spherical shell is proposed. The modified iteration method considering large deflection of the shell is applied to solve the problem of nonlinear stability of the shallow spherical shells, and then the second-order approximate analytical solution is obtained. The critical pressure calculated by this method is consistent with the classical numerical results and nonlinear finite element method, and the calculation errors are less than 10%. It shows that it is feasible to apply the method proposed here.
2
Ghosh, Arghya, and Dipankar Chakravorty. "Uniformly Loaded Composite Hypar Shell Roofs Under Progressive Failure." In 5th International Congress on Computational Mechanics and Simulation. Singapore: Research Publishing Services, 2014. http://dx.doi.org/10.3850/978-981-09-1139-3_050.
Full text
3
Chen, Zhiping, Huan Gao, Wenjing Guo, Fucai Chen, Ji Wang, and Weirong Hong. "Design of a New Bearing on the Large Net Shell Roof Tank." In ASME 2012 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/pvp2012-78636.
Full textAbstract:
The structure of the plate rib roof can’t meet the need of the constantly enlarging storage tanks, thus more steel/aluminum net shell roofs have been used on the large storage tanks. The bearing between the roof and the tank wall is a key component, because it directly affects the strength and stability of the net shell roof. In this paper, a new type of net shell roof bearing structure is proposed in order to relieve the stress on the bearing and the net shell roof. The proposed structure has several features compared with the existing bearings: the net shell roof with the new bearing can allow a certain amount of radial displacement, and the bearing can also rotate within a certain angle. According to the actual loading status, strength and stability analysis of the overall net shell roof and the bearing’s partial structure are carried out respectively. The overall model of the net shell roof is established by ANSYS, and different boundary conditions are defined on the roof under two working conditions of “full-span live load” and “half-span live load”. Then the overall static strength calculation and stability analysis of the roof are completed. Based on the results of the overall analysis, the strength of the bearing’s partial model is analyzed in ANSYS Workbench. Research shows that when the net shell roof is under load, the roof is allowed to make radial displacement and the bearing to make angular displacement. Thus the burden on the bearing and the net shell roof is relieved, and the strength and stability of the overall roof meet the requirements. Moreover, many regions of the bearing can share the horizontal force, which helps to reduce the load on the bolts and improve the safety of the bearing structure. And the strength of the bearing meets the requirements.
4
Yoshida, Shoichi, and Kazuhiro Kitamura. "Buckling Characteristics of Floating Roof Pontoons in Aboveground Storage Tanks Subjected to Bending Load in Two Directions." In ASME 2008 Pressure Vessels and Piping Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/pvp2008-61085.
Full textAbstract:
The 2003 Tokachi-Oki earthquake caused severe damage to aboveground oil storage tanks due to liquid sloshing. Seven single-deck floating roofs had experienced structural problems as evidenced by sinking failure in large diameter tanks at the refinery in Tomakomai, Japan. The pontoons of the floating roofs might be buckled due to circumferential bending moment during the sloshing. The content in the tank was spilled on the floating roof from small failures which were caused at the welding joints of pontoon bottom plate by the buckling. Then the floating roof began to lose buoyancy and submerged into the content slowly. The authors had reported the buckling strength of the pontoons with and without ring stiffeners subjected to circumferential bending load in the previous papers. This paper presents the buckling strength of the pontoons subjected to both circumferential and radial bending load. The axisymmetric shell finite element method is used in the analysis. Linear elastic bifurcation buckling analysis is carried out and the buckling characteristics of the pontoon with and without ring stiffeners are investigated.
5
Yoshida, Shoichi, and Kazuhiro Kitamura. "Buckling of Ring Stiffened Pontoons of Floating Roofs in Aboveground Oil Storage Tanks." In ASME 2007 Pressure Vessels and Piping Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/pvp2007-26252.
Full textAbstract:
The 2003 Tokachi-Oki earthquake caused severe damage to oil storage tanks due to liquid sloshing. Six single-deck floating roofs had experienced structural problems as evidenced by sinking failure in large diameter tanks at the refinery in Tomakomai, Japan. The pontoon of floating roof might be buckled due to circumferential bending moment during the sloshing. The content in the tank was spilled on the floating roof from small failures which might be caused in the lap-welded joints or in the stress concentrated parts of the pontoon bottom plate by the buckling. Then the floating roof began to lose buoyancy and submerged into the content slowly. The failure of the roof expanded gradually in the sinking process. It is presumed that the initial small failures were caused by the elastic buckling of the pontoon due to circumferential bending moment. In this paper, the buckling strength of the pontoon is presented using axisymmetric shell finite element analysis. Linear elastic bifurcation buckling analyses are carried out and the buckling characteristics of ring stiffened pontoons are investigated.
6
Bernard, Gary, Damien Vera, and Weng Kheong Lim. "Seismic Response Analysis of Flexible Drain System Into External Floating Roof Storage Tanks." In ASME 2017 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/pvp2017-65524.
Full textAbstract:
Floating roofs are commonly used worldwide on top of cylindrical oil storage tanks as a primary means to prevent formation of vapor above stored products into the storage tanks and should provide a safe and efficient storage of products with minimal risk for the environment. However, aboveground storage reservoirs built in seismic zones are prone to earthquake damage. Extensive research has been done to enhance performance of the floating roof tanks against damage to ground foundations, fixed and floating roof, tank shells as well as adjacent piping. Indeed, the stored oil sloshing in a cylindrical storage tank is known to have caused damage to the tank shell, tank roof and as well to anti-rotation columns. One of the possible dangers of liquid sloshing is the resultant damage to in-situ roof drain systems within external floating roof tanks. Indeed, roof drain systems are designed for continuous withdrawal of rainwater from external floating roofs, and if damaged, would result in dysfunction of the systems and irreversible discharge of oil products into the containment dyke. In this regard, a reliable roof drain system should have the capability to withstand liquid sloshing effects, and to a certain degree, ensure resistance in events of displacement of the floating roof. The aim of this document is to use knowledge of flexible pipe technology and industry recognized dynamic analysis software to analyze the effects of earthquakes on the integrity of a flexible drain pipe system. Analysis of liquid sloshing effects on flexible drain pipe systems using dynamic analysis software will be presented and the effects of structural damages such as loss of anti-rotation columns on the integrity of flexible drain pipe systems will be assessed. In the end, the document will propose recommendations on how industry can further enhance roof drain systems within external floating roof tanks to ensure performance and functionality after occurrence of earthquakes.
7
Yoshida, Shoichi. "Axisymmetric Finite Element Analysis for Floating Roofs of Aboveground Storage Tanks Under Accumulated Rain Water Condition." In ASME 2011 Pressure Vessels and Piping Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/pvp2011-57457.
Full textAbstract:
The floating roofs are used in large aboveground storage tanks to prevent evaporation of the content. The single-deck floating roof, which is considered herein, consists of a thin circular plate called a deck attached to a buoyant ring of box-shaped cross section called a pontoon. Under the accumulated rain water condition, the deck is deflected largely, and both its edge part and the pontoon are compressed circumferentially. Since the load condition due to the rain water depends on the deflected deck shape, it is difficult to find the unique equilibrium condition. This paper describes the deformation analysis for the single-deck floating roofs under the accumulated rain water condition using the geometrically nonlinear axisymmetric shell finite element method. The load incremental method, in which the equivalent nodal forces due to the rain water converges to coincide with the rain water load derived from both the current rain water volume and the deflected deck shape, is used.
8
Yoshida, Shoichi, and Kazuhiro Kitamura. "Buckling of Single-Deck Floating Roofs in Aboveground Oil Storage Tanks Due to Circumferential Bending Load." In ASME 2006 Pressure Vessels and Piping/ICPVT-11 Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/pvp2006-icpvt-11-93696.
Full textAbstract:
The 2003 Tokachi-Oki earthquake caused severe damage to oil storage tanks due to liquid sloshing. Six single-deck floating roofs had experienced structural problems as evidenced by sinking failure in large diameter tanks at the refinery at Tomakomai, Japan. The pontoon of floating roof might be buckled due to circumferential bending moment during the sloshing. The content in the tank was spilled on the floating roof from small failures which were caused in the rap welding joints of pontoon bottom plate by the buckling. Then the floating roof began to lose buoyancy and submerged into the content slowly. The failure of the roof expanded gradually in the sinking process. It is presumed that the initial small failures were caused by the elastic buckling of the pontoon due to circumferential bending moment. This paper presents the buckling strength of the pontoon using axisymmetric shell finite element analysis. Linear elastic bifurcation buckling analysis is carried out and the buckling characteristics of the pontoon are investigated. The result shows that the thickness of both pontoon roof and bottom plates have significantly affect the buckling strength.
9
Yoshida, Shoichi. "Buckling Characteristics of Floating Roof Pontoons in Aboveground Storage Tanks Subjected to Both Compressive and Bending Load." In ASME 2009 Pressure Vessels and Piping Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/pvp2009-77227.
Full textAbstract:
The 2003 Tokachi-Oki earthquake caused severe damage to oil storage tanks due to liquid sloshing. Seven single-deck floating roofs had experienced structural problems as evidenced by sinking failure in large diameter tanks at a refinery in Tomakomai, Japan. The pontoons of the floating roofs might be buckled due to circumferential bending moment during the sloshing. The content in the tank was spilled on the floating roof from small failures which were caused in the welding joints of pontoon bottom plate by the buckling. Then the floating roof began to lose buoyancy and sank into the content slowly. The authors had reported the buckling strength of the pontoons subjected to circumferential bending load first and that of the pontoons subjected to both circumferential and radial bending load next in the previous papers. This paper presents the buckling strength of the pontoons subjected to both circumferential bending load and circumferential compressive load. The axisymmetric shell finite element method is used in the analysis. Linear elastic bifurcation buckling analysis is carried out and the buckling characteristics of the pontoon both with and without ring stiffeners are investigated.
10
Yoshida, Shoichi. "Lower Bound Buckling Load of a Floating Roof Pontoon." In ASME 2010 Pressure Vessels and Piping Division/K-PVP Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/pvp2010-25092.
Full textAbstract:
The 2003 Tokachi-Oki earthquake caused severe damage to oil storage tanks due to liquid sloshing. Seven single-deck floating roofs had experienced sinking failures in large diameter tanks at a refinery in Tomakomai, Japan. The pontoons of the floating roofs might be buckled due to bending load during the sloshing. The content in the tank was spilled on the floating roof from small failures which were caused in the welding joints of pontoon bottom plate by the buckling. Then the floating roof began to lose buoyancy and sank into the content slowly. The elastic buckling of the pontoon is important from the viewpoint of the single-deck floating roof sinking. The authors had reported the buckling strength of the pontoons subjected to bending and compressive loads in the published literatures. The axisymmetric shell finite element method for linear elastic bifurcation buckling was used in the analysis. The buckling characteristics of the pontoon both with and without ring stiffeners were investigated. The initial geometrical imperfection may diminish the buckling load. This paper presents the lower bound buckling load according to the reduced stiffness method proposed by Croll and Yamada. The lower bound buckling loads of the pontoon subjected to circumferential bending load are evaluated from the axisymmetric finite element analysis which includes the reduced stiffness method.
Reports on the topic "Shell Roofs"
1
Phillips, Donald A., Yitzhak Spiegel, and Howard Ferris. Optimizing nematode management by defining natural chemical bases of behavior. United States Department of Agriculture, November 2006. http://dx.doi.org/10.32747/2006.7587234.bard.
Full textAbstract:
This project was based on the hypothesis that nematodes interacting with plants as either parasites or beneficial saprophytes are attracted to their host by natural products. This concept was supported by numerous observations that parasitic nematodes are attracted to root exudates. Our overall goal was to identify nematode sensory compounds from root exudates and to use that information for reducing nematicide applications. We applied skills of the investigators to achieve three specific objectives: 1) Identify nematode behavioral cues (e.g., attractants or repellents) in root exudates; 2) Identify new natural nematicidal compounds; and 3) Combine a natural attractant and a nematicide into a nematode trap. Because saprophytic nematodes benefit plants by mineralizing organic matter, we sought compounds attractive primarily to parasitic nematodes. The project was constructed on several complementary foundations. First, data from Dr. Spiegel’s lab showed that under aseptic conditions Ditylenchus dipsaci, a parasite on onion, is attracted to certain fractions of onion root exudates. Second, PI Phillips had a sizeable collection of natural plant products he had identified from previous work on Rhizobium-legume interactions, which could be tested “off the shelf”. Third, Dr. Ferris had access to aseptic and natural populations of various saprophytic and parasitic nematodes. The project focused on five nematode species: D.dipsaci, Heterodera avenae, and Tylenchulussemipenetransat ARO, and Meloidogyne javanicand Caenorhabditis elegans at UCD. Ten pure plant compounds, mostly flavonoids, were tested on the various nematode species using six different assay systems. Results obtained with assorted test systems and by various scientists in the same test systems were essentially irreproducible. Many convincing, Many convincing, i.e. statistically significant, results in one system or with one investigator could not be repeated with other assays or different people. A recent report from others found that these compounds, plus another 30, were inactive as attractants in three additional parasitic nematode species (Wuyts et al. Nematology 8:89- 101, 2006). Assays designed to test the hypothesis that several compounds together are required to attract nematodes have thus far failed to find a reproducibly active combination. In contrast to results using pure plant compounds, complex unfractionated exudates from aseptic onion root reproducibly attracted D. dipsaci in both the ARO and UCD labs. Onion root exudate collection, separation into HPLC fractions, assays using D. dipsaci and MS-MS experiments proceeded collaboratively between ARO and UCD without any definitive identification of an active compound. The final active fraction contained two major molecules and traces of several other compounds. In the end, analytical studies were limited by the amount of onion root exudate and the complexity of the purification process. These tests showed that aseptic plant roots release attractant molecules, but whether nematodes influence that release, as insects trigger release of attractants from plants, is unknown. Related experiments showed that the saprophyte C. elegans stimulates its prey, Pseudomonas bacteria, to increase production of 2, 4-diacetylphloroglucinol (DAPG) a compound that promotes amino acid exudation by plant roots. It is thus possible that saprophytic nematodes are attracted primarily to their bacterial or fungal prey and secondarily to effects of those microorganisms on root exudation. These observations offer promising avenues for understanding root-zone interactions, but no direct routes to controlling nematodes in agriculture were evident. Extracts from two plant sources, Chrysanthemum coronarium and Sequoia sempervirens, showed nematicidal activity at ARO and UCD, respectively. Attempts to purify an active compound from S. sempervirens failed, but preliminary results from C. coronarium are judged to form a potential basis for further work at ARO. These results highlight the problems of studying complex movement patterns in sentient organisms like nematodes and the issues associated with natural product isolation from complex mixtures. Those two difficulties combined with complications now associated with obtaining US visas, slowed and ultimately limited progress on this project. As a result, US investigators expended only 65% of the $207,400 originally planned for this project. The Israeli side of the project advanced more directly toward its scientific goals and lists its expenditures in the customary financial report.
2
Galili, Naftali, Roger P. Rohrbach, Itzhak Shmulevich, Yoram Fuchs, and Giora Zauberman. Non-Destructive Quality Sensing of High-Value Agricultural Commodities Through Response Analysis. United States Department of Agriculture, October 1994. http://dx.doi.org/10.32747/1994.7570549.bard.
Full textAbstract:
The objectives of this project were to develop nondestructive methods for detection of internal properties and firmness of fruits and vegetables. One method was based on a soft piezoelectric film transducer developed in the Technion, for analysis of fruit response to low-energy excitation. The second method was a dot-matrix piezoelectric transducer of North Carolina State University, developed for contact-pressure analysis of fruit during impact. Two research teams, one in Israel and the other in North Carolina, coordinated their research effort according to the specific objectives of the project, to develop and apply the two complementary methods for quality control of agricultural commodities. In Israel: An improved firmness testing system was developed and tested with tropical fruits. The new system included an instrumented fruit-bed of three flexible piezoelectric sensors and miniature electromagnetic hammers, which served as fruit support and low-energy excitation device, respectively. Resonant frequencies were detected for determination of firmness index. Two new acoustic parameters were developed for evaluation of fruit firmness and maturity: a dumping-ratio and a centeroid of the frequency response. Experiments were performed with avocado and mango fruits. The internal damping ratio, which may indicate fruit ripeness, increased monotonically with time, while resonant frequencies and firmness indices decreased with time. Fruit samples were tested daily by destructive penetration test. A fairy high correlation was found in tropical fruits between the penetration force and the new acoustic parameters; a lower correlation was found between this parameter and the conventional firmness index. Improved table-top firmness testing units, Firmalon, with data-logging system and on-line data analysis capacity have been built. The new device was used for the full-scale experiments in the next two years, ahead of the original program and BARD timetable. Close cooperation was initiated with local industry for development of both off-line and on-line sorting and quality control of more agricultural commodities. Firmalon units were produced and operated in major packaging houses in Israel, Belgium and Washington State, on mango and avocado, apples, pears, tomatoes, melons and some other fruits, to gain field experience with the new method. The accumulated experimental data from all these activities is still analyzed, to improve firmness sorting criteria and shelf-life predicting curves for the different fruits. The test program in commercial CA storage facilities in Washington State included seven apple varieties: Fuji, Braeburn, Gala, Granny Smith, Jonagold, Red Delicious, Golden Delicious, and D'Anjou pear variety. FI master-curves could be developed for the Braeburn, Gala, Granny Smith and Jonagold apples. These fruits showed a steady ripening process during the test period. Yet, more work should be conducted to reduce scattering of the data and to determine the confidence limits of the method. Nearly constant FI in Red Delicious and the fluctuations of FI in the Fuji apples should be re-examined. Three sets of experiment were performed with Flandria tomatoes. Despite the complex structure of the tomatoes, the acoustic method could be used for firmness evaluation and to follow the ripening evolution with time. Close agreement was achieved between the auction expert evaluation and that of the nondestructive acoustic test, where firmness index of 4.0 and more indicated grade-A tomatoes. More work is performed to refine the sorting algorithm and to develop a general ripening scale for automatic grading of tomatoes for the fresh fruit market. Galia melons were tested in Israel, in simulated export conditions. It was concluded that the Firmalon is capable of detecting the ripening of melons nondestructively, and sorted out the defective fruits from the export shipment. The cooperation with local industry resulted in development of automatic on-line prototype of the acoustic sensor, that may be incorporated with the export quality control system for melons. More interesting is the development of the remote firmness sensing method for sealed CA cool-rooms, where most of the full-year fruit yield in stored for off-season consumption. Hundreds of ripening monitor systems have been installed in major fruit storage facilities, and being evaluated now by the consumers. If successful, the new method may cause a major change in long-term fruit storage technology. More uses of the acoustic test method have been considered, for monitoring fruit maturity and harvest time, testing fruit samples or each individual fruit when entering the storage facilities, packaging house and auction, and in the supermarket. This approach may result in a full line of equipment for nondestructive quality control of fruits and vegetables, from the orchard or the greenhouse, through the entire sorting, grading and storage process, up to the consumer table. The developed technology offers a tool to determine the maturity of the fruits nondestructively by monitoring their acoustic response to mechanical impulse on the tree. A special device was built and preliminary tested in mango fruit. More development is needed to develop a portable, hand operated sensing method for this purpose. In North Carolina: Analysis method based on an Auto-Regressive (AR) model was developed for detecting the first resonance of fruit from their response to mechanical impulse. The algorithm included a routine that detects the first resonant frequency from as many sensors as possible. Experiments on Red Delicious apples were performed and their firmness was determined. The AR method allowed the detection of the first resonance. The method could be fast enough to be utilized in a real time sorting machine. Yet, further study is needed to look for improvement of the search algorithm of the methods. An impact contact-pressure measurement system and Neural Network (NN) identification method were developed to investigate the relationships between surface pressure distributions on selected fruits and their respective internal textural qualities. A piezoelectric dot-matrix pressure transducer was developed for the purpose of acquiring time-sampled pressure profiles during impact. The acquired data was transferred into a personal computer and accurate visualization of animated data were presented. Preliminary test with 10 apples has been performed. Measurement were made by the contact-pressure transducer in two different positions. Complementary measurements were made on the same apples by using the Firmalon and Magness Taylor (MT) testers. Three-layer neural network was designed. 2/3 of the contact-pressure data were used as training input data and corresponding MT data as training target data. The remaining data were used as NN checking data. Six samples randomly chosen from the ten measured samples and their corresponding Firmalon values were used as the NN training and target data, respectively. The remaining four samples' data were input to the NN. The NN results consistent with the Firmness Tester values. So, if more training data would be obtained, the output should be more accurate. In addition, the Firmness Tester values do not consistent with MT firmness tester values. The NN method developed in this study appears to be a useful tool to emulate the MT Firmness test results without destroying the apple samples. To get more accurate estimation of MT firmness a much larger training data set is required. When the larger sensitive area of the pressure sensor being developed in this project becomes available, the entire contact 'shape' will provide additional information and the neural network results would be more accurate. It has been shown that the impact information can be utilized in the determination of internal quality factors of fruit. Until now,
3
IMPERFECTION SENSITIVITY OF NON-TRIANGULATED CYLINDRICAL SHELL CONFIGURATIONS. The Hong Kong Institute of Steel Construction, August 2022. http://dx.doi.org/10.18057/icass2020.p.280.
Full textAbstract:
Non-triangulated lattice shells are rarely adopted for large structures due to their lower resistance and stability compared to triangulated shells. As a result, only a few studies are available for the stability evaluation of non-triangulated shell configurations. However, these shell structures can be used for roofs with lower dimensions and lower resistance requirements. As studies related to the imperfection of non-triangulated shell structures are rare, an attempt has been made to study the effect of initial geometric imperfection on the overall resistance of cylindrical shells created using parameterisation principles. The influence of the different magnitude of initial geometric imperfection on the overall resistance of non-triangulated reticulated shells was studied under the uniform gravity load. The results illustrate the significant influence of initial geometric imperfection on the load capacity of non-triangulated shell configurations compared to the triangulated shell configurations. The effect of the initial geometric imperfection on the load capacity increases with the edge valency of faces and decreases with the edge valency of vertices. This study provides information to designers for designing non-triangulated shell structures by considering initial geometric imperfections encountered in the system.
4
SEISMIC PERFORMANCE OF SINGLE-LAYER SPHERICAL RETICULATED SHELLS CONSIDERING JOINT STIFFNESS AND BEARING CAPACITY. The Hong Kong Institute of Steel Construction, June 2022. http://dx.doi.org/10.18057/ijasc.2022.18.2.9.
Full textAbstract:
Fabricated joints are gradually applied in architectural structures because of their advantages of good economy, high installation quality and efficiency. However, the mechanical properties of this kind of joint are semi-rigid differing from traditional rigid and hinged joints. Therefore, the performance of the structures with such joints is not clear, which greatly limits the wide application of fabricated joints. This paper presents the investigation on the seismic performance of the semi-rigid single-layer reticulated shell structure (SRSS) under earthquake load by numerical simulation and theoretical analysis. A finite element model (FEM) of the semi-rigid reticulated shell was established. The influence of joint stiffness on the seismic performance of semi-rigid SRSS was obtained by taking both initial defects and material damage accumulation into account. The two design parameters, limit stiffness ratio and limit yield moment of the joints, were proposed for the semi-rigid reticulated shells. The influence of the roof span, roof weight and member section on the two design parameters was obtained and the calculation formula was established. The seismic force coefficient for the semi-rigid SRSS was obtained, which can provide support for the seismic design of semi-rigid SRSS.