Documents disponibles écrits par cet auteur

Analysis of wind-induced clip loads on standing seam metal roofs / Murray J. Morrison in Journal of structural engineering, Vol. 136 N° 3 (Mars 2010) 

Public ISBD [article]  in Journal of structural engineering > Vol. 136 N° 3 (Mars 2010) . - pp. 334-337 Titre : Analysis of wind-induced clip loads on standing seam metal roofs Type de document : texte imprimé Auteurs : Murray J. Morrison, Auteur ; Gregory A. Kopp, Auteur Année de publication : 2011 Article en page(s) : pp. 334-337 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Wind  loads  Roof  failures  Buildings  Low-rise  Standards  and  codes  Aerodynamics Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : The current investigation extends the previous work in calculating components and cladding loads for standing seam metal roof clips. It was found that the ASCE 7-05 wind loads for these clips are conservative, while several other studies have shown that the ASCE 7-05 is unconservative when compared to integrated wind tunnel pressure data. The current note resolves this contradiction, showing that the observed conservatism is primarily due to the fact that the critical clips are not located in the worst aerodynamic region of the roof. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v136/i3/p334_s1?isAuthorized=no [article] Analysis of wind-induced clip loads on standing seam metal roofs [texte imprimé] / Murray J. Morrison, Auteur ; Gregory A. Kopp, Auteur . - 2011 . - pp. 334-337. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 136 N° 3 (Mars 2010) . - pp. 334-337 Mots-clés : Wind  loads  Roof  failures  Buildings  Low-rise  Standards  and  codes  Aerodynamics Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : The current investigation extends the previous work in calculating components and cladding loads for standing seam metal roof clips. It was found that the ASCE 7-05 wind loads for these clips are conservative, while several other studies have shown that the ASCE 7-05 is unconservative when compared to integrated wind tunnel pressure data. The current note resolves this contradiction, showing that the observed conservatism is primarily due to the fact that the critical clips are not located in the worst aerodynamic region of the roof. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v136/i3/p334_s1?isAuthorized=no

Effects of pressure equalization on the performance of residential wall systems under extreme wind loads / Gregory A. Kopp in Journal of structural engineering, Vol. 138 N° 4 (Avril 2012) 

Public ISBD [article]  in Journal of structural engineering > Vol. 138 N° 4 (Avril 2012) . - pp. 526–538 Titre : Effects of pressure equalization on the performance of residential wall systems under extreme wind loads Type de document : texte imprimé Auteurs : Gregory A. Kopp, Auteur ; Eri Gavanski, Auteur Année de publication : 2012 Article en page(s) : pp. 526–538 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Full-scale  tests  Hurricanes  Walls  Wind  loads  Wood  structure Résumé : During strong windstorms, sheathing and siding on residential, wood-framed, wall systems have commonly failed. In the current study, a clear difference is observed in the rate of failure occurrence for wall sheathing above or below the eaves. This observation can be explained from tests examining ultimate capacities and pressure equalization of both single- and multilayer residential, wood-framed, wall systems using realistic fluctuating loads. The results indicate that pressure equalization is a critical parameter in the performance of both the cladding and exterior sheathing. With interior sheathing included, significant pressure equalization was observed to occur across the exterior sheathing, because pressure equalization is observed to increase with load (and damage) levels. This substantially increases the ultimate capacity of these wall systems; however, the construction details of the various exterior layers play an important role in the levels of pressure equalization across each layer. ISSN : 0733-9445 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29ST.1943-541X.0000476 [article] Effects of pressure equalization on the performance of residential wall systems under extreme wind loads [texte imprimé] / Gregory A. Kopp, Auteur ; Eri Gavanski, Auteur . - 2012 . - pp. 526–538. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 138 N° 4 (Avril 2012) . - pp. 526–538 Mots-clés : Full-scale  tests  Hurricanes  Walls  Wind  loads  Wood  structure Résumé : During strong windstorms, sheathing and siding on residential, wood-framed, wall systems have commonly failed. In the current study, a clear difference is observed in the rate of failure occurrence for wall sheathing above or below the eaves. This observation can be explained from tests examining ultimate capacities and pressure equalization of both single- and multilayer residential, wood-framed, wall systems using realistic fluctuating loads. The results indicate that pressure equalization is a critical parameter in the performance of both the cladding and exterior sheathing. With interior sheathing included, significant pressure equalization was observed to occur across the exterior sheathing, because pressure equalization is observed to increase with load (and damage) levels. This substantially increases the ultimate capacity of these wall systems; however, the construction details of the various exterior layers play an important role in the levels of pressure equalization across each layer. ISSN : 0733-9445 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29ST.1943-541X.0000476

Evaluation of quasi-steady theory applied to windborne flat plates in uniform flow / Bahareh Kordi in Journal of engineering mechanics, Vol. 135 N° 7 (Juillet 2009) 

Public ISBD [article]  in Journal of engineering mechanics > Vol. 135 N° 7 (Juillet 2009) . - pp. 657-668 Titre : Evaluation of quasi-steady theory applied to windborne flat plates in uniform flow Type de document : texte imprimé Auteurs : Bahareh Kordi, Auteur ; Gregory A. Kopp, Auteur Article en page(s) : pp. 657-668 Note générale : Mécanique appliquée Langues : Anglais (eng) Mots-clés : Wind  loads  Debris  Aerodynamics  Turbulence  Plates  Uniform  flow. Résumé : This paper analyzes models based on the quasi-steady theory for the flight of windborne plate debris. It is shown that the effects of the rotational lift, drag, and pitching moment are important and are included in the model. The model was used with success to predict the behavior of thin, square plates in a uniform stream, based on comparisons with existing experimental data. In fact, some of the scatter in the existing experimental data was explained by the numerical results. It was also shown that the buoyancy parameter was the key parameter in determining initial flight speeds and normalization of spatial coordinates with this parameter collapsed the data well. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/vsearch/servlet/VerityServlet?KEY=JENMDT&smode=strres [...] [article] Evaluation of quasi-steady theory applied to windborne flat plates in uniform flow [texte imprimé] / Bahareh Kordi, Auteur ; Gregory A. Kopp, Auteur . - pp. 657-668. Mécanique appliquée Langues : Anglais (eng) in Journal of engineering mechanics > Vol. 135 N° 7 (Juillet 2009) . - pp. 657-668 Mots-clés : Wind  loads  Debris  Aerodynamics  Turbulence  Plates  Uniform  flow. Résumé : This paper analyzes models based on the quasi-steady theory for the flight of windborne plate debris. It is shown that the effects of the rotational lift, drag, and pitching moment are important and are included in the model. The model was used with success to predict the behavior of thin, square plates in a uniform stream, based on comparisons with existing experimental data. In fact, some of the scatter in the existing experimental data was explained by the numerical results. It was also shown that the buoyancy parameter was the key parameter in determining initial flight speeds and normalization of spatial coordinates with this parameter collapsed the data well. DEWEY : 620.1 ISSN : 0733-9399 En ligne : http://ascelibrary.aip.org/vsearch/servlet/VerityServlet?KEY=JENMDT&smode=strres [...]

Horizontal wind loads on open-frame, low-rise buildings / Gregory A. Kopp in Journal of structural engineering, Vol. 136 N° 1 (Janvier 2010) 

Public ISBD [article]  in Journal of structural engineering > Vol. 136 N° 1 (Janvier 2010) . - pp. 98-105 Titre : Horizontal wind loads on open-frame, low-rise buildings Type de document : texte imprimé Auteurs : Gregory A. Kopp, Auteur ; Jon K. Galsworthy, Auteur ; Jeong Hee Oh, Auteur Année de publication : 2011 Article en page(s) : pp. 98-105 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Wind  loads  Buildings  Low-rise  Aerodynamics  Standards  and  codes Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : Wind tunnel tests of open-frame, low-rise buildings were carried out to determine the drag (base shear) and bracing loads in the direction normal to the frames (parallel to the ridge). In total, 18 configurations were examined in an open country terrain at a scale of 1:100. The worst wind angles for all configurations are between 0°–40° with 20°–30° typically yielding slightly higher loads, 0° being parallel to the ridge. The largest load coefficients are observed for the smallest frame buildings, consistent with observations for enclosed buildings, which is due to three-dimensional (edge) effects. The solidity ratio has a clear effect on the load coefficients with higher coefficients for lower solidity, similar to the behavior observed on lattice frames or trussed towers. However, when these coefficients are multiplied by the solidity ratio, so that they can be directly compared to enclosed building coefficients, it is clear that the total load increases monotonically with solid area. Bracing was observed to take up to 75% of the total drag load. An empirical model was developed for obtaining design loads. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v136/i1/p98_s1?bypassSSO=1 [article] Horizontal wind loads on open-frame, low-rise buildings [texte imprimé] / Gregory A. Kopp, Auteur ; Jon K. Galsworthy, Auteur ; Jeong Hee Oh, Auteur . - 2011 . - pp. 98-105. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 136 N° 1 (Janvier 2010) . - pp. 98-105 Mots-clés : Wind  loads  Buildings  Low-rise  Aerodynamics  Standards  and  codes Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : Wind tunnel tests of open-frame, low-rise buildings were carried out to determine the drag (base shear) and bracing loads in the direction normal to the frames (parallel to the ridge). In total, 18 configurations were examined in an open country terrain at a scale of 1:100. The worst wind angles for all configurations are between 0°–40° with 20°–30° typically yielding slightly higher loads, 0° being parallel to the ridge. The largest load coefficients are observed for the smallest frame buildings, consistent with observations for enclosed buildings, which is due to three-dimensional (edge) effects. The solidity ratio has a clear effect on the load coefficients with higher coefficients for lower solidity, similar to the behavior observed on lattice frames or trussed towers. However, when these coefficients are multiplied by the solidity ratio, so that they can be directly compared to enclosed building coefficients, it is clear that the total load increases monotonically with solid area. Bracing was observed to take up to 75% of the total drag load. An empirical model was developed for obtaining design loads. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v136/i1/p98_s1?bypassSSO=1

Storm and gust duration effects on design wind loads for glass / Eri Gavanski in Journal of structural engineering, Vol. 137 N° 12 (Décembre 2011) 

Public ISBD [article]  in Journal of structural engineering > Vol. 137 N° 12 (Décembre 2011) . - pp. 1603-1610 Titre : Storm and gust duration effects on design wind loads for glass Type de document : texte imprimé Auteurs : Eri Gavanski, Auteur ; Gregory A. Kopp, Auteur Année de publication : 2012 Article en page(s) : pp. 1603-1610 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Standards  and  codes  Wind  loads  Window  glass Résumé : Duration effects on the design wind loads for glass are examined with respect to ASCE 7-10. Pressure time histories are created by combining variations of wind speed and wind direction from a “design cyclone” with pressure coefficients obtained from wind tunnel tests of low-rise buildings. The results indicate that the assumption of a 3-s gust duration in ASCE 7-10 may underestimate appropriate values for design loads for glass, with the degree of underestimation varying, depending primarily on the probability of exceedence of the peak pressures. On the basis of these results, modifications to the peak pressures specified in ASCE 7-10 are suggested that maintain the time duration of 3-s, consistent with current glass-design provisions. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v137/i12/p1603_s1?isAuthorized=no [article] Storm and gust duration effects on design wind loads for glass [texte imprimé] / Eri Gavanski, Auteur ; Gregory A. Kopp, Auteur . - 2012 . - pp. 1603-1610. Génie Civil Langues : Anglais (eng) in Journal of structural engineering > Vol. 137 N° 12 (Décembre 2011) . - pp. 1603-1610 Mots-clés : Standards  and  codes  Wind  loads  Window  glass Résumé : Duration effects on the design wind loads for glass are examined with respect to ASCE 7-10. Pressure time histories are created by combining variations of wind speed and wind direction from a “design cyclone” with pressure coefficients obtained from wind tunnel tests of low-rise buildings. The results indicate that the assumption of a 3-s gust duration in ASCE 7-10 may underestimate appropriate values for design loads for glass, with the degree of underestimation varying, depending primarily on the probability of exceedence of the peak pressures. On the basis of these results, modifications to the peak pressures specified in ASCE 7-10 are suggested that maintain the time duration of 3-s, consistent with current glass-design provisions. DEWEY : 624.17 ISSN : 0733-9445 En ligne : http://ascelibrary.org/sto/resource/1/jsendh/v137/i12/p1603_s1?isAuthorized=no

Use of the wind tunnel test method for obtaining design wind loads on roof-mounted solar arrays / Gregory A. Kopp in Journal of structural engineering, Vol. 139 N° 2 (Février 2013) 

Permalink