Construction of electric arc welded railway bridges developed in France with the work of Chief En... more Construction of electric arc welded railway bridges developed in France with the work of Chief Engineer Louis Eugène Cambournac (1886-1973) within the Compagnie des Chemins de fer du Nord from 1935 onwards, then within the SNCF (French Railways) from 1938. Under the impetus of this Chief Engineer, about ten railway bridges were built, including only one truss bridge, the Joncherolles Bridge, put into service on 15 May 1939. During this period, the electric arc welding process was used to reinforce riveted bridges not strong enough to support the increase in loads and frequency of railway traffic. It was also used for repairing corroded riveted railway bridges, and occasionally following destructions that occurred during the Second World War. This study shows, in this transition period, how the electric arc welding process quickly-but quite latelybecame established for the construction of French railway bridges, replacing the hot riveting process.
'hoge performantie' wanneer andere eigenschappen dan hoge weerstand worden beoogd. Betonwand: Mee... more 'hoge performantie' wanneer andere eigenschappen dan hoge weerstand worden beoogd. Betonwand: Meestal verticale muur in gewapend beton. Cement: Cement is een hydraulisch bindmiddel, d.w.z. een fijn gemalen, anorganisch materiaal dat, vermengd met water, een pasta vormt die uithardt als gevolg van hydrateringsreacties en na uitharding zelfs onder water zijn weerstand en stabiliteit behoudt. Cementmelk: Mengsel van watercement en toeslagstoffen, gebruikt om barsten te injecteren en kabelgoten of voorspanningsstaven te vullen. Centerpengaten: Gaten in de bekistingspanelen van wanden in gewapend beton, voor de plaatsing van tijdelijke pennen die de BOUWWERKEN VAN BETON IN ACHT CHRONOLOGISCHE TYPOLOGIEËN
Les contributions belges marquantes à une histoire internationale du béton et des structures en b... more Les contributions belges marquantes à une histoire internationale du béton et des structures en béton peuvent se résumer comme suit. Le pionnier français du béton armé, François Hennebique, a commencé, dans les années 1890, à construire son empire international à partir de la Belgique. C'est l'ingénieur belge Paul Christophe qui, en 1902, a écrit le premier livre permettant le dimensionnement rationnel du béton armé, base des méthodes de calcul universellement utilisées jusque dans les années 1970. La société liégeoise Franki a joué un rôle international de premier plan dans le développement des techniques de fondation, et pour l'édition de la revue La Technique des Travaux. Le professeur gantois Gustave Magnel, associé à l 'entreprise bruxelloise Blaton-Aubert, a joué un rôle majeur dans le développement et la promotion du béton précontraint. Ces situations, ces contributions, ces entreprises ont eu un impact fondamental dans l'histoire de la construction internationale. LE BÉTON AVANT LE BÉTON ARMÉ Le béton n'a pas été inventé au XX e siècle, ni même au XIX e siècle. S e s or igine s s ont bien plus anciennes : elles remontent à l'Antiquité. Vitruve, au I er siècle avant Jésus-Christ, donne dans son traité De Architectura des « recettes » de composition de béton. Les constructeurs romains ont fait un usage abondant de ce matériau, fort probablement précédés par les Grecs.
Cet article rapporte les resultats de l'application de la technique de mesure de contraintes ... more Cet article rapporte les resultats de l'application de la technique de mesure de contraintes in situ par liberation partielle a un grand pont en maconnerie de pierre, le pont Adolphe a Luxembourg du a P. Sejourne. Pour disposer les verins plats, on pratiqua douze entailles de 60 cm de large dans des sections situees pres des naissances de l'arc. La methode de mesure de contrainte par liberation partielle et restauration au moyen de verins plats s'est averee utilisable. Elle a fourni dans la maconnerie des valeurs de contraintes coherentes et realistes, bien inferieures a la resistance intrinseque. (A) (Titres en anglais, en allemand et en espagnol : Stress measurements by release of tension in the Adolphe bridge, a large arch designed by P. Sejourne - Messung der Belastung mit flachen Druckmessdosen an der von P. Sejourne entworfenen Adolphe-Bruecke in Luxemburg - Mediciones de tensiones por liberacion en el puente Adolphe de Luxemburgo, gran boveda de P. Sejourne).
As testimony of the engineering development during the industrial revolution, old riveted bridges... more As testimony of the engineering development during the industrial revolution, old riveted bridges are maintained by several policies worldwide and in some cases because of their historical importance protected. A main concern of these policies is preserving their structural integrity, which depends on a fatigue assessment of their components and assemblies. In these structures, the stress ratio considerably affects the fatigue strength, but the actual standards do not consider this fact. Some deterministic models have been proposed in order to overcome this issue. However, they are based on restrictive and empirical assumptions. Moreover, no statistical considerations are made, although fatigue strength is a random variable. In this paper, the suggested models are studied and then enhanced by statistical considerations. Finally, a statistical fatigue strength model as function of the stress ratio is proposed and applied on riveted specimens from old German Bridges and newly manufact...
Fatigue & Fracture of Engineering Materials & Structures, 2020
Old riveted railway bridges are part of the cultural and technological heritage in many countries... more Old riveted railway bridges are part of the cultural and technological heritage in many countries. The assessment of the actual behaviour and the remaining life of these structures is a key economical factor in the management of these bridges. This evaluation should take into account the evolution of the traffic loads, which have constantly increased since their construction, and a realistic estimation of the fatigue life derived from representative experimental tests.This study deals with the fatigue behaviour of riveted assemblies with specimens prepared from materials sampled in two old bridges: a railway bridge over the Adour river (France) built in 1862–1864 and the Stahringer bridge (Germany), constructed in 1895. Because all assemblies are not subjected to the same loads, this research concentrates on the influence of the stress ratio R on the fatigue behaviour. In order to quantify this influence, a comparison between the Basquin linear model and the Weibull model is perform...
Building Knowledge, Constructing Histories, Volume 1, 2018
Most European traders, conquerors and colonists sought to build familiar settlements in unfamilia... more Most European traders, conquerors and colonists sought to build familiar settlements in unfamiliar surroundings. These ambitions were often challenged by scarcity of known building materials, skilled labour and the demands of alien climatic conditions. To find suitable translations of European building techniques, observation of local construction methods and their selective appropriation solved many such difficulties. This paper is largely based on articles in military and learned journals published in Britain and India in which non-European building practices and materials were described and illustrated not as exotic curiosities but as ideas worthy of emulation, until they were set aside in favour of the supposedly superior products of European mechanical industry and scientific knowledge. The paper will focus on three Indian modes of building that gained wide admiration and comment beyond the subcontinent. These are: Superior Chunam mortars capable of fine finishes and waterproofing, ingenious vaulting techniques with reduced lateral thrust erected with minimal falsework and well foundations, a reliable alternative to piling.
'hoge performantie' wanneer andere eigenschappen dan hoge weerstand worden beoogd. Betonwand: Mee... more 'hoge performantie' wanneer andere eigenschappen dan hoge weerstand worden beoogd. Betonwand: Meestal verticale muur in gewapend beton. Cement: Cement is een hydraulisch bindmiddel, d.w.z. een fijn gemalen, anorganisch materiaal dat, vermengd met water, een pasta vormt die uithardt als gevolg van hydrateringsreacties en na uitharding zelfs onder water zijn weerstand en stabiliteit behoudt. Cementmelk: Mengsel van watercement en toeslagstoffen, gebruikt om barsten te injecteren en kabelgoten of voorspanningsstaven te vullen. Centerpengaten: Gaten in de bekistingspanelen van wanden in gewapend beton, voor de plaatsing van tijdelijke pennen die de BOUWWERKEN VAN BETON IN ACHT CHRONOLOGISCHE TYPOLOGIEËN
Construction of electric arc welded railway bridges developed in France with the work of Chief En... more Construction of electric arc welded railway bridges developed in France with the work of Chief Engineer Louis Eugène Cambournac (1886-1973) within the Compagnie des Chemins de fer du Nord from 1935 onwards, then within the SNCF (French Railways) from 1938. Under the impetus of this Chief Engineer, about ten railway bridges were built, including only one truss bridge, the Joncherolles Bridge, put into service on 15 May 1939. During this period, the electric arc welding process was used to reinforce riveted bridges not strong enough to support the increase in loads and frequency of railway traffic. It was also used for repairing corroded riveted railway bridges, and occasionally following destructions that occurred during the Second World War. This study shows, in this transition period, how the electric arc welding process quickly-but quite latelybecame established for the construction of French railway bridges, replacing the hot riveting process.
'hoge performantie' wanneer andere eigenschappen dan hoge weerstand worden beoogd. Betonwand: Mee... more 'hoge performantie' wanneer andere eigenschappen dan hoge weerstand worden beoogd. Betonwand: Meestal verticale muur in gewapend beton. Cement: Cement is een hydraulisch bindmiddel, d.w.z. een fijn gemalen, anorganisch materiaal dat, vermengd met water, een pasta vormt die uithardt als gevolg van hydrateringsreacties en na uitharding zelfs onder water zijn weerstand en stabiliteit behoudt. Cementmelk: Mengsel van watercement en toeslagstoffen, gebruikt om barsten te injecteren en kabelgoten of voorspanningsstaven te vullen. Centerpengaten: Gaten in de bekistingspanelen van wanden in gewapend beton, voor de plaatsing van tijdelijke pennen die de BOUWWERKEN VAN BETON IN ACHT CHRONOLOGISCHE TYPOLOGIEËN
Les contributions belges marquantes à une histoire internationale du béton et des structures en b... more Les contributions belges marquantes à une histoire internationale du béton et des structures en béton peuvent se résumer comme suit. Le pionnier français du béton armé, François Hennebique, a commencé, dans les années 1890, à construire son empire international à partir de la Belgique. C'est l'ingénieur belge Paul Christophe qui, en 1902, a écrit le premier livre permettant le dimensionnement rationnel du béton armé, base des méthodes de calcul universellement utilisées jusque dans les années 1970. La société liégeoise Franki a joué un rôle international de premier plan dans le développement des techniques de fondation, et pour l'édition de la revue La Technique des Travaux. Le professeur gantois Gustave Magnel, associé à l 'entreprise bruxelloise Blaton-Aubert, a joué un rôle majeur dans le développement et la promotion du béton précontraint. Ces situations, ces contributions, ces entreprises ont eu un impact fondamental dans l'histoire de la construction internationale. LE BÉTON AVANT LE BÉTON ARMÉ Le béton n'a pas été inventé au XX e siècle, ni même au XIX e siècle. S e s or igine s s ont bien plus anciennes : elles remontent à l'Antiquité. Vitruve, au I er siècle avant Jésus-Christ, donne dans son traité De Architectura des « recettes » de composition de béton. Les constructeurs romains ont fait un usage abondant de ce matériau, fort probablement précédés par les Grecs.
Cet article rapporte les resultats de l'application de la technique de mesure de contraintes ... more Cet article rapporte les resultats de l'application de la technique de mesure de contraintes in situ par liberation partielle a un grand pont en maconnerie de pierre, le pont Adolphe a Luxembourg du a P. Sejourne. Pour disposer les verins plats, on pratiqua douze entailles de 60 cm de large dans des sections situees pres des naissances de l'arc. La methode de mesure de contrainte par liberation partielle et restauration au moyen de verins plats s'est averee utilisable. Elle a fourni dans la maconnerie des valeurs de contraintes coherentes et realistes, bien inferieures a la resistance intrinseque. (A) (Titres en anglais, en allemand et en espagnol : Stress measurements by release of tension in the Adolphe bridge, a large arch designed by P. Sejourne - Messung der Belastung mit flachen Druckmessdosen an der von P. Sejourne entworfenen Adolphe-Bruecke in Luxemburg - Mediciones de tensiones por liberacion en el puente Adolphe de Luxemburgo, gran boveda de P. Sejourne).
As testimony of the engineering development during the industrial revolution, old riveted bridges... more As testimony of the engineering development during the industrial revolution, old riveted bridges are maintained by several policies worldwide and in some cases because of their historical importance protected. A main concern of these policies is preserving their structural integrity, which depends on a fatigue assessment of their components and assemblies. In these structures, the stress ratio considerably affects the fatigue strength, but the actual standards do not consider this fact. Some deterministic models have been proposed in order to overcome this issue. However, they are based on restrictive and empirical assumptions. Moreover, no statistical considerations are made, although fatigue strength is a random variable. In this paper, the suggested models are studied and then enhanced by statistical considerations. Finally, a statistical fatigue strength model as function of the stress ratio is proposed and applied on riveted specimens from old German Bridges and newly manufact...
Fatigue & Fracture of Engineering Materials & Structures, 2020
Old riveted railway bridges are part of the cultural and technological heritage in many countries... more Old riveted railway bridges are part of the cultural and technological heritage in many countries. The assessment of the actual behaviour and the remaining life of these structures is a key economical factor in the management of these bridges. This evaluation should take into account the evolution of the traffic loads, which have constantly increased since their construction, and a realistic estimation of the fatigue life derived from representative experimental tests.This study deals with the fatigue behaviour of riveted assemblies with specimens prepared from materials sampled in two old bridges: a railway bridge over the Adour river (France) built in 1862–1864 and the Stahringer bridge (Germany), constructed in 1895. Because all assemblies are not subjected to the same loads, this research concentrates on the influence of the stress ratio R on the fatigue behaviour. In order to quantify this influence, a comparison between the Basquin linear model and the Weibull model is perform...
Building Knowledge, Constructing Histories, Volume 1, 2018
Most European traders, conquerors and colonists sought to build familiar settlements in unfamilia... more Most European traders, conquerors and colonists sought to build familiar settlements in unfamiliar surroundings. These ambitions were often challenged by scarcity of known building materials, skilled labour and the demands of alien climatic conditions. To find suitable translations of European building techniques, observation of local construction methods and their selective appropriation solved many such difficulties. This paper is largely based on articles in military and learned journals published in Britain and India in which non-European building practices and materials were described and illustrated not as exotic curiosities but as ideas worthy of emulation, until they were set aside in favour of the supposedly superior products of European mechanical industry and scientific knowledge. The paper will focus on three Indian modes of building that gained wide admiration and comment beyond the subcontinent. These are: Superior Chunam mortars capable of fine finishes and waterproofing, ingenious vaulting techniques with reduced lateral thrust erected with minimal falsework and well foundations, a reliable alternative to piling.
'hoge performantie' wanneer andere eigenschappen dan hoge weerstand worden beoogd. Betonwand: Mee... more 'hoge performantie' wanneer andere eigenschappen dan hoge weerstand worden beoogd. Betonwand: Meestal verticale muur in gewapend beton. Cement: Cement is een hydraulisch bindmiddel, d.w.z. een fijn gemalen, anorganisch materiaal dat, vermengd met water, een pasta vormt die uithardt als gevolg van hydrateringsreacties en na uitharding zelfs onder water zijn weerstand en stabiliteit behoudt. Cementmelk: Mengsel van watercement en toeslagstoffen, gebruikt om barsten te injecteren en kabelgoten of voorspanningsstaven te vullen. Centerpengaten: Gaten in de bekistingspanelen van wanden in gewapend beton, voor de plaatsing van tijdelijke pennen die de BOUWWERKEN VAN BETON IN ACHT CHRONOLOGISCHE TYPOLOGIEËN
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