A l/10 scale model of reinforced concrete (R C ) frame structure was tested on the 15t-shaking table of State Key Laboratory, Tongji University The structural prototype was a 10-storey office building that was damag...A l/10 scale model of reinforced concrete (R C ) frame structure was tested on the 15t-shaking table of State Key Laboratory, Tongji University The structural prototype was a 10-storey office building that was damaged in the 1985 Mexico major earthquake[1] The original acceleration records in the earthquake were applied as the input waves in the test The dynamical test model was designed according to the general law of similarity, and the effect of the shortage of artificial quality was considered The model was carefully made of fine gravel concrete and galvanized iron wire The damage of test model is in good agreement with that of archetypal building in the experiment展开更多
In this note, we establish a new characterization on g-frames in Hilbert C;-modules from the operator-theoretic point of view, with which we provide a correction to one result recently obtained by Yao(Yao X Y. Some pr...In this note, we establish a new characterization on g-frames in Hilbert C;-modules from the operator-theoretic point of view, with which we provide a correction to one result recently obtained by Yao(Yao X Y. Some properties of g-frames in Hilbert C;-modules(in Chinese). Acta Math. Sinica, 2011, 54(1): 1–8.).展开更多
The design provisions of current seismic codes are generally not very accurate for assessing effects of near-fault ground motions on reinforced concrete (r.c.) spatial frames, because only far-fault ground motions a...The design provisions of current seismic codes are generally not very accurate for assessing effects of near-fault ground motions on reinforced concrete (r.c.) spatial frames, because only far-fault ground motions are considered in the seismic codes. Strong near-fault earth- quakes are characterized by long-duration (horizontal) pulses and high values of the ratio ~PGA of the peak value of the vertical acceleration, PGAv, to the analogous value of the horizontal acceleration, PGAH, which can become critical for girders and columns. In this work, six- and twelve-storey r.c. spatial frames are designed according to the provisions of the Italian seismic code, considering the horizontal seismic loads acting (besides the gravity loads) alone or in combination with the vertical ones. The non- linear seismic analysis of the test structures is performed using a step-by-step procedure based on a two-parameter implicit integration scheme and an initial stress-like itera- tive procedure. A lumped plasticity model based on the Haar-K^n~m principle is adopted to model the inelastic behaviour of the frame members. For the numerical investigation, five near-fault ground motions with high values of the acceleration ratio C^p6A are considered. Moreover, following recent seismological studies, which allow the extraction of the largest (horizontal) pulse from a near-fault ground motion, five pulse-type (horizontal) ground motions are selected by comparing the original ground motion with the residual motion after the pulse has been extracted. The results of the nonlinear dynamic analysis carried out on the test structures highlighted thathorizontal and vertical components of near-fault ground motions may require additional consideration in the seis- mic codes.展开更多
In the paper, we introduce weak Bessel sequences and weak frames in a Hilbert C*-module 74, and give a characterization of weak Bessel sequences, weak frames, normalized tight weak frames, and dual weak frames to eac...In the paper, we introduce weak Bessel sequences and weak frames in a Hilbert C*-module 74, and give a characterization of weak Bessel sequences, weak frames, normalized tight weak frames, and dual weak frames to each other, respectively. Using .A-valued linear bounded operator U : H → l^2(.A), V*U = I, a coustructing method of dual weak frame {xj^* : j ∈ H} for a given weak frame {Xj : j ∈ J} is obtained. Moreover, pseudo frame decompositions for 74 is given.展开更多
In order to study the dynamic behaviour of construction,specifically seismic response of structures,as many researchers did,we have resorted to modelling methods,based on the scaled internal forces.Therefore,this rese...In order to study the dynamic behaviour of construction,specifically seismic response of structures,as many researchers did,we have resorted to modelling methods,based on the scaled internal forces.Therefore,this research includes results of an experimental investigation aimed to establish the possibility of realistic simulations of the cyclic response of small-scale models of one bay,one-storey reinforced concrete frames with masonry infills as a preliminary step for simulating the dynamic response of such structural.So,the specimens constructed were 1:9 scale R/C frames.These 1:9 scale infill frames were constructed with prototype materials and were tested in an extensive experimental sequence representing specimens of a scale near the prototype(1:3).The tested laboratory models include 1:3 scale infilled R/C frames that were built from original material such as steel,concrete and masonry infills(hollow masonry units and mortar).With the same scale,geometry and construction materials used for the construction of a 1:3 scale 5-story three dimensional building.This program consisted of 16 models,5 bare and 11 masonry infilled.all models refer to single-storey one-bay 1:9 scale as for the original structure and a one third of the scale(1:3)as for the prototype(1:3).The reinforced concrete specimens were designed in such a way as to prevent shear failure of the columns.Finally,the present paper was carried out in the Laboratory of Strength of Materials and Structures in the Department of Civil Engineering at Aristotle University of Thessaloniki.展开更多
In this paper we discuss about c-frames, namely continuous frames. Since, cframes are generalizations of discrete frames, we generalize some results of discrete frames to continuous version. We explain some results ab...In this paper we discuss about c-frames, namely continuous frames. Since, cframes are generalizations of discrete frames, we generalize some results of discrete frames to continuous version. We explain some results about relations of projections in Hilbert spaces and c-frames to characterize these frames. Also, we will specify(precisely) the synthesis and frame operators of Bochner integrable c-frames. Finally, we classify Hilbert-Schmidt operators by c-frames and express some new identities for Parseval c-frames.展开更多
基金the Sustentation Fundation of State Key Laboratory,Tongji University (970809D2)
文摘A l/10 scale model of reinforced concrete (R C ) frame structure was tested on the 15t-shaking table of State Key Laboratory, Tongji University The structural prototype was a 10-storey office building that was damaged in the 1985 Mexico major earthquake[1] The original acceleration records in the earthquake were applied as the input waves in the test The dynamical test model was designed according to the general law of similarity, and the effect of the shortage of artificial quality was considered The model was carefully made of fine gravel concrete and galvanized iron wire The damage of test model is in good agreement with that of archetypal building in the experiment
基金The NSF(11271148,11561057)of Chinathe NSF(20151BAB201007)of Jiangxi Provincethe Science and Technology Project(GJJ151061)of Jiangxi Education Department
文摘In this note, we establish a new characterization on g-frames in Hilbert C;-modules from the operator-theoretic point of view, with which we provide a correction to one result recently obtained by Yao(Yao X Y. Some properties of g-frames in Hilbert C;-modules(in Chinese). Acta Math. Sinica, 2011, 54(1): 1–8.).
文摘The design provisions of current seismic codes are generally not very accurate for assessing effects of near-fault ground motions on reinforced concrete (r.c.) spatial frames, because only far-fault ground motions are considered in the seismic codes. Strong near-fault earth- quakes are characterized by long-duration (horizontal) pulses and high values of the ratio ~PGA of the peak value of the vertical acceleration, PGAv, to the analogous value of the horizontal acceleration, PGAH, which can become critical for girders and columns. In this work, six- and twelve-storey r.c. spatial frames are designed according to the provisions of the Italian seismic code, considering the horizontal seismic loads acting (besides the gravity loads) alone or in combination with the vertical ones. The non- linear seismic analysis of the test structures is performed using a step-by-step procedure based on a two-parameter implicit integration scheme and an initial stress-like itera- tive procedure. A lumped plasticity model based on the Haar-K^n~m principle is adopted to model the inelastic behaviour of the frame members. For the numerical investigation, five near-fault ground motions with high values of the acceleration ratio C^p6A are considered. Moreover, following recent seismological studies, which allow the extraction of the largest (horizontal) pulse from a near-fault ground motion, five pulse-type (horizontal) ground motions are selected by comparing the original ground motion with the residual motion after the pulse has been extracted. The results of the nonlinear dynamic analysis carried out on the test structures highlighted thathorizontal and vertical components of near-fault ground motions may require additional consideration in the seis- mic codes.
基金Supported by the Emphasis Supported Subject Foundation of Shanxi Province(20055026) Supported by the Emphasis Science Foundation of Yuncheng University(20060103)
文摘In the paper, we introduce weak Bessel sequences and weak frames in a Hilbert C*-module 74, and give a characterization of weak Bessel sequences, weak frames, normalized tight weak frames, and dual weak frames to each other, respectively. Using .A-valued linear bounded operator U : H → l^2(.A), V*U = I, a coustructing method of dual weak frame {xj^* : j ∈ H} for a given weak frame {Xj : j ∈ J} is obtained. Moreover, pseudo frame decompositions for 74 is given.
文摘In order to study the dynamic behaviour of construction,specifically seismic response of structures,as many researchers did,we have resorted to modelling methods,based on the scaled internal forces.Therefore,this research includes results of an experimental investigation aimed to establish the possibility of realistic simulations of the cyclic response of small-scale models of one bay,one-storey reinforced concrete frames with masonry infills as a preliminary step for simulating the dynamic response of such structural.So,the specimens constructed were 1:9 scale R/C frames.These 1:9 scale infill frames were constructed with prototype materials and were tested in an extensive experimental sequence representing specimens of a scale near the prototype(1:3).The tested laboratory models include 1:3 scale infilled R/C frames that were built from original material such as steel,concrete and masonry infills(hollow masonry units and mortar).With the same scale,geometry and construction materials used for the construction of a 1:3 scale 5-story three dimensional building.This program consisted of 16 models,5 bare and 11 masonry infilled.all models refer to single-storey one-bay 1:9 scale as for the original structure and a one third of the scale(1:3)as for the prototype(1:3).The reinforced concrete specimens were designed in such a way as to prevent shear failure of the columns.Finally,the present paper was carried out in the Laboratory of Strength of Materials and Structures in the Department of Civil Engineering at Aristotle University of Thessaloniki.
文摘In this paper we discuss about c-frames, namely continuous frames. Since, cframes are generalizations of discrete frames, we generalize some results of discrete frames to continuous version. We explain some results about relations of projections in Hilbert spaces and c-frames to characterize these frames. Also, we will specify(precisely) the synthesis and frame operators of Bochner integrable c-frames. Finally, we classify Hilbert-Schmidt operators by c-frames and express some new identities for Parseval c-frames.