To develop a high performance buckling-restrained brace （BRB） with less weight, an innovative type of the BRB with transverse rib restraints is proposed and studied through experiment. Three BRB specimens are cyclic...To develop a high performance buckling-restrained brace （BRB） with less weight, an innovative type of the BRB with transverse rib restraints is proposed and studied through experiment. Three BRB specimens are cyclically loaded in the investigation. Specimen 1 adopts a Q235 core member and transverse rib restraints. Specimen 2 adopts a LYP160 low yield point steel core member and transverse rib restraints. Specimen 3 adopts a LYP160 low yield point steel core member and mortar restraint. The experimental results indicate that the transverse rib restraining mode can provide sufficient lateral stiffness for the core member and effectively restrain its buckling. The BRB specimens with a LYP160 core member exhibit better hysteretic performance and energy dissipation capacity than the specimens with a Q235 core member.展开更多
In considering the theory of structural dynamic optimization design, a design method of the structural style of ship composite brace with rigid vibration isolation mass was studied. Two kinds of structural dynamic opt...In considering the theory of structural dynamic optimization design, a design method of the structural style of ship composite brace with rigid vibration isolation mass was studied. Two kinds of structural dynamic optimization formulations minimizing the vibration acceleration of the non-pressure hull on the restraining condition of the gross weight of the ship cabin were established: 1) dynamic optimization of the sectional dimensions of the rigid vibration isolation mass in the composite brace; 2) dynamic optimization of the arranging position of the rigid vibration isolation mass. Through the optimization results, sectional dimensions and the arranging position of the rigid vibration isolation mass with better performance in reducing vibration were gained, and some reference was provided for practical engineering designs as well as enrichment of the design method of a novel ship vibration-isolation brace.展开更多
Based on the features of the serious deformation of coal roadway,many random variables of the mechanics of the surrounding rocks and the influence of mining, the reliability analysis model of the support structure of ...Based on the features of the serious deformation of coal roadway,many random variables of the mechanics of the surrounding rocks and the influence of mining, the reliability analysis model of the support structure of coal roadway under the influence of mining is established,and the calculating formulas of reliability of the support structure is obtained with the engineering structure reliability theory. And the reliability is calculated based on the method of Monte Carlo to the coal roadway which is exampled on the influence of mining or not. The relationship between support parameters and reliability, the mining influence coefficients and reliability is established, which provides theory foundations for the design of the coal roadway bolt support.展开更多
By conformal mapping theory, a trigonometric interpolation method between odd and even sequences in rectangle boundary region was provided, and the conformal mapping function of rectangle-plate with arc radius between...By conformal mapping theory, a trigonometric interpolation method between odd and even sequences in rectangle boundary region was provided, and the conformal mapping function of rectangle-plate with arc radius between complicated region and unite dish region was carried out. Aiming at calculating the vibrating fundamental frequency of special-shaped, elastic simple-supported rectangle-plates, in the in-plane state of constant stress, the vibration function of this complicated plate was depicted by unit dish region. The coefficient of ftmdamental frequency was calculated. Whilst, taking simple-supported elastic rectangle-plates with arc radius as an example, the effects on fundamental frequency caused by the concentrated mass and position, the ratio of the length to width of rectangle, as well as the coefficient of constant in-plane stress were analyzed respectively.展开更多
Geologists can offer key insights in regard to several high profile environmental issues that are faced today. At the same time, like scientists in most other disciplines, many geologists are not naturally adept at co...Geologists can offer key insights in regard to several high profile environmental issues that are faced today. At the same time, like scientists in most other disciplines, many geologists are not naturally adept at communicating in an effective manner with non-geologists. This paper firstly identifies the more subtle facets of topical major issues （the drivers） where geologists can contribute important perspectives. Next, the detractions to effective communication are identified, along with the recommended means to overcome them （the mechanisms）. Many topical issues are in fact geologically-underpinned （e.g. obviously, geohazards）, so geologists ought to have something meaningful to say. By the same token, if geologists have difficulty communicating with other scientists, how can they possibly hope to communicate with journalists and with the public at large？ Proper scientific contextualization is an ideal starting point, but this fundamental framing step does not always suit protagonists who have non-scientific agendas. Thus, geologists not only have to convey their science （geology） in an understandable way, but to do so in a truly effective manner must recognize and take into account possible predispositions that their audience may have.展开更多
基金The National Key Technology R&D Program of China during the12th Five-Year Plan Period(No.2012BAJ13B01)the Science and Technology Program of the Ministry of Housing and UrbanRural Development(No.2011-K2-3)+1 种基金the Science and Technology Foundation of Southeast University(No.9205000034)the Priority Academic Program Development of Jiangsu Higher Education Institutions(No.CE01-2-09)
文摘To develop a high performance buckling-restrained brace （BRB） with less weight, an innovative type of the BRB with transverse rib restraints is proposed and studied through experiment. Three BRB specimens are cyclically loaded in the investigation. Specimen 1 adopts a Q235 core member and transverse rib restraints. Specimen 2 adopts a LYP160 low yield point steel core member and transverse rib restraints. Specimen 3 adopts a LYP160 low yield point steel core member and mortar restraint. The experimental results indicate that the transverse rib restraining mode can provide sufficient lateral stiffness for the core member and effectively restrain its buckling. The BRB specimens with a LYP160 core member exhibit better hysteretic performance and energy dissipation capacity than the specimens with a Q235 core member.
基金Supported by the Shipbuilding Industry of National Defense Science and Technology Research Projects in Advance (153010110031)
文摘In considering the theory of structural dynamic optimization design, a design method of the structural style of ship composite brace with rigid vibration isolation mass was studied. Two kinds of structural dynamic optimization formulations minimizing the vibration acceleration of the non-pressure hull on the restraining condition of the gross weight of the ship cabin were established: 1) dynamic optimization of the sectional dimensions of the rigid vibration isolation mass in the composite brace; 2) dynamic optimization of the arranging position of the rigid vibration isolation mass. Through the optimization results, sectional dimensions and the arranging position of the rigid vibration isolation mass with better performance in reducing vibration were gained, and some reference was provided for practical engineering designs as well as enrichment of the design method of a novel ship vibration-isolation brace.
基金a grant from the National Natural Science Foundation of China (No. 50674046)a grant from the Scientific Research Fund of Hunan Provincial Education Department(No. 07C293).
文摘Based on the features of the serious deformation of coal roadway,many random variables of the mechanics of the surrounding rocks and the influence of mining, the reliability analysis model of the support structure of coal roadway under the influence of mining is established,and the calculating formulas of reliability of the support structure is obtained with the engineering structure reliability theory. And the reliability is calculated based on the method of Monte Carlo to the coal roadway which is exampled on the influence of mining or not. The relationship between support parameters and reliability, the mining influence coefficients and reliability is established, which provides theory foundations for the design of the coal roadway bolt support.
文摘By conformal mapping theory, a trigonometric interpolation method between odd and even sequences in rectangle boundary region was provided, and the conformal mapping function of rectangle-plate with arc radius between complicated region and unite dish region was carried out. Aiming at calculating the vibrating fundamental frequency of special-shaped, elastic simple-supported rectangle-plates, in the in-plane state of constant stress, the vibration function of this complicated plate was depicted by unit dish region. The coefficient of ftmdamental frequency was calculated. Whilst, taking simple-supported elastic rectangle-plates with arc radius as an example, the effects on fundamental frequency caused by the concentrated mass and position, the ratio of the length to width of rectangle, as well as the coefficient of constant in-plane stress were analyzed respectively.
文摘Geologists can offer key insights in regard to several high profile environmental issues that are faced today. At the same time, like scientists in most other disciplines, many geologists are not naturally adept at communicating in an effective manner with non-geologists. This paper firstly identifies the more subtle facets of topical major issues （the drivers） where geologists can contribute important perspectives. Next, the detractions to effective communication are identified, along with the recommended means to overcome them （the mechanisms）. Many topical issues are in fact geologically-underpinned （e.g. obviously, geohazards）, so geologists ought to have something meaningful to say. By the same token, if geologists have difficulty communicating with other scientists, how can they possibly hope to communicate with journalists and with the public at large？ Proper scientific contextualization is an ideal starting point, but this fundamental framing step does not always suit protagonists who have non-scientific agendas. Thus, geologists not only have to convey their science （geology） in an understandable way, but to do so in a truly effective manner must recognize and take into account possible predispositions that their audience may have.
