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2006 Vol. 36, No. 2
Display Method:
2006, 36(2): 1-4.
doi: 10.13204/j.gyjz200602001
Abstract:
It is explored the vibrational energy dissipation theory of a new dry friction damper and its application in vibration control of a building . The research shows that the new dampers have traditional dampersc merit and overcome the shortcoming that can only offer invariable friction. At the same time, they can be controlled by the signal of the vibration of the building . So the ability of energy dissipation and vibration control effect is augmented. The simulation using finite element program proved that the vibration of the building is reduced with the use of this damper.
It is explored the vibrational energy dissipation theory of a new dry friction damper and its application in vibration control of a building . The research shows that the new dampers have traditional dampersc merit and overcome the shortcoming that can only offer invariable friction. At the same time, they can be controlled by the signal of the vibration of the building . So the ability of energy dissipation and vibration control effect is augmented. The simulation using finite element program proved that the vibration of the building is reduced with the use of this damper.
2006, 36(2): 5-7.
doi: 10.13204/j.gyjz200602002
Abstract:
It is introduced the experiment of the dynamic mechanical properties between the ageing viscoelastic dampers and the nonag ing viscoelastic dampers. It is also explained the improvement cause of ageing characteristics for VE dampers that the great majority of VE material is enwrapped by the steel plates to prevent from the air directly.
It is introduced the experiment of the dynamic mechanical properties between the ageing viscoelastic dampers and the nonag ing viscoelastic dampers. It is also explained the improvement cause of ageing characteristics for VE dampers that the great majority of VE material is enwrapped by the steel plates to prevent from the air directly.
2006, 36(2): 8-10.
doi: 10.13204/j.gyjz200602003
Abstract:
It is presented that the vibration attenuation mechanism and the practical engineering application of the rectangle shallow Liquid Damper. Through the experimental investigation on the 4-floor steel frame under harmonic excitation, it is also compared the deformation and acceleration response without control and with control, and is concluded that the TLD system can control the first and second vibration modal of the structure effectively.
It is presented that the vibration attenuation mechanism and the practical engineering application of the rectangle shallow Liquid Damper. Through the experimental investigation on the 4-floor steel frame under harmonic excitation, it is also compared the deformation and acceleration response without control and with control, and is concluded that the TLD system can control the first and second vibration modal of the structure effectively.
2006, 36(2): 11-15.
doi: 10.13204/j.gyjz200602004
Abstract:
Firstly, influencing factors of structural damping dissipation under vibration are analyzed and two kinds of different damping dissipations are defined. T hen, RC bending elements are researched where damping is taken as spatial distributing energy dissipation. By research of relationships between damping dissipation and spatial distributing stress amplitude in vibration, the formula for damping energy dissipation and spatial distributing stress amplitude is presented, which including concrete strength, ratio of stirrup and maximum shearing stress. Finally, stress amplitude coefficient n and damping dissipation factor J are obtained based on other test results.
Firstly, influencing factors of structural damping dissipation under vibration are analyzed and two kinds of different damping dissipations are defined. T hen, RC bending elements are researched where damping is taken as spatial distributing energy dissipation. By research of relationships between damping dissipation and spatial distributing stress amplitude in vibration, the formula for damping energy dissipation and spatial distributing stress amplitude is presented, which including concrete strength, ratio of stirrup and maximum shearing stress. Finally, stress amplitude coefficient n and damping dissipation factor J are obtained based on other test results.
2006, 36(2): 16-19.
doi: 10.13204/j.gyjz200602005
Abstract:
It is analyzed that random vibration spectrum and time history curve of reflection of mega-sub controlled structural system subjected to seismic loads. It is also observed that this new kind of structural system holds more merits of resisting seismic forces. The seismic reflections of the structure may be depressed further, when dampers are appropriately fixed in the sensitive part of the structure, which makes the best of dissipation capacity of dampers and can not weaken tuned advantage of subframes. For this new building system, viscous dampers are proposed, which can easily be actualized in practical engineering, can not change natural frequency of structure and produce prominent controlling effect.
It is analyzed that random vibration spectrum and time history curve of reflection of mega-sub controlled structural system subjected to seismic loads. It is also observed that this new kind of structural system holds more merits of resisting seismic forces. The seismic reflections of the structure may be depressed further, when dampers are appropriately fixed in the sensitive part of the structure, which makes the best of dissipation capacity of dampers and can not weaken tuned advantage of subframes. For this new building system, viscous dampers are proposed, which can easily be actualized in practical engineering, can not change natural frequency of structure and produce prominent controlling effect.
2006, 36(2): 20-23.
doi: 10.13204/j.gyjz200602006
Abstract:
B ased on the low cyclic repeated horizontal loading test of R C hollow shear walls with flanges, The failure mechanism, the deformation feature, ductility behavior and the strain of steel bar at section are discussed. The method for calculating the carrying capacity of this sort of shear wall is presented.
B ased on the low cyclic repeated horizontal loading test of R C hollow shear walls with flanges, The failure mechanism, the deformation feature, ductility behavior and the strain of steel bar at section are discussed. The method for calculating the carrying capacity of this sort of shear wall is presented.
2006, 36(2): 24-27.
doi: 10.13204/j.gyjz200602007
Abstract:
The dynamic property is analyzed for a new braces compound structure of mult-i story residence. Based on dynamics theory of structure and the equations of dynamics characteristics of the structure, the effects of different areas of the brace, numbers of story and mass of floor on dynamics characteristics are analyzed. The calculating results show the action of braces advances the frequency and shear stiffness of the structure, and the frequency would increase monotonously with adding of brace section. The frequency would reduce with adding numbers of story and mass of floor. According to the frequencyc s calculation of the equations of dynamics characteristics, frequency curves are draw up and a frequency formula considering the stiffness of column and braces, floorsc numbers and mass of the compound structure is obtained. The formula is simple and consonant with theory equation.
The dynamic property is analyzed for a new braces compound structure of mult-i story residence. Based on dynamics theory of structure and the equations of dynamics characteristics of the structure, the effects of different areas of the brace, numbers of story and mass of floor on dynamics characteristics are analyzed. The calculating results show the action of braces advances the frequency and shear stiffness of the structure, and the frequency would increase monotonously with adding of brace section. The frequency would reduce with adding numbers of story and mass of floor. According to the frequencyc s calculation of the equations of dynamics characteristics, frequency curves are draw up and a frequency formula considering the stiffness of column and braces, floorsc numbers and mass of the compound structure is obtained. The formula is simple and consonant with theory equation.
2006, 36(2): 28-30.
doi: 10.13204/j.gyjz200602008
Abstract:
It is des igned a contrast experiment on two s ets of two-s pan and two- story RC frames under low cycle reversed loading, One frame has construction joints while the other has not. According to the experiment results, hysteres is behavior, ductility, rigidity degeneration etc. are studied systematically. And studies show that the RC frame without construction joints has better seismic performance than the other .
It is des igned a contrast experiment on two s ets of two-s pan and two- story RC frames under low cycle reversed loading, One frame has construction joints while the other has not. According to the experiment results, hysteres is behavior, ductility, rigidity degeneration etc. are studied systematically. And studies show that the RC frame without construction joints has better seismic performance than the other .
2006, 36(2): 31-33.
doi: 10.13204/j.gyjz200602009
Abstract:
As human association space was enlarged increasingly, the role of interior public spaces in society has become more and more important, whose function and space organization designed tend to diversification. From the point of view of acoustics, it is analysed that status and the timbre vices appearing currently in various interior public spaces, and the corresponding objects and measures of timbre design are suggested and reinterpreted by two ex amples.
As human association space was enlarged increasingly, the role of interior public spaces in society has become more and more important, whose function and space organization designed tend to diversification. From the point of view of acoustics, it is analysed that status and the timbre vices appearing currently in various interior public spaces, and the corresponding objects and measures of timbre design are suggested and reinterpreted by two ex amples.
2006, 36(2): 34-36.
doi: 10.13204/j.gyjz2006020010
Abstract:
With the natural environment destroying, it becomes a trend to construct ecological campus of college and university. The measures for improving relevant thermal micro_environment are explored according to its exterior environment, site selection, campus planning, architectural design and building energy_saving to ensure good thermal micro_ environment in an ecological campus.
With the natural environment destroying, it becomes a trend to construct ecological campus of college and university. The measures for improving relevant thermal micro_environment are explored according to its exterior environment, site selection, campus planning, architectural design and building energy_saving to ensure good thermal micro_ environment in an ecological campus.
2006, 36(2): 37-38.
doi: 10.13204/j.gyjz200602011
Abstract:
Taking the iterm of Dalian innovative accessory industry park for innovative accessories for example, it is expounded the relation between the design of a modern industrial workshop and exterior environmental combination, the connection between interior space combination and architecture modeling disposal.
Taking the iterm of Dalian innovative accessory industry park for innovative accessories for example, it is expounded the relation between the design of a modern industrial workshop and exterior environmental combination, the connection between interior space combination and architecture modeling disposal.
2006, 36(2): 39-41.
doi: 10.13204/j.gyjz200602012
Abstract:
It has been put forward the necessity of designing eco- architecture by the theoretical analysis of ecological buildings correctly, and realtors should seize the opportunity and build the real ecological buildings. It has also been put forward the concrete measures and methods by actual building examples to realize sustainable development.
It has been put forward the necessity of designing eco- architecture by the theoretical analysis of ecological buildings correctly, and realtors should seize the opportunity and build the real ecological buildings. It has also been put forward the concrete measures and methods by actual building examples to realize sustainable development.
2006, 36(2): 42-44.
doi: 10.13204/j.gyjz200602013
Abstract:
The reliability analysis of rock-socketed support structures with rea-l time deformation control during the construction process is proposed and carried out in a practical big and deep exvacation engineering. The comparison to reliability analysis with so- called whole deformation control is made. Itc s proved reliability analysis with rea-l time deformation control during the construction process has more practical meaning and the safety of support structures will be guaranteed gradually.
The reliability analysis of rock-socketed support structures with rea-l time deformation control during the construction process is proposed and carried out in a practical big and deep exvacation engineering. The comparison to reliability analysis with so- called whole deformation control is made. Itc s proved reliability analysis with rea-l time deformation control during the construction process has more practical meaning and the safety of support structures will be guaranteed gradually.
2006, 36(2): 45-49.
doi: 10.13204/j.gyjz200602014
Abstract:
It is introduced the definition of effective bending rigidity ratios and moment increasing rates, and it also discusses the method which can be used to determine the effective bending rigidity ratios and moment increasing rates with beam-spring modal. The effect of the joint stiffness on the effective bending rigidity ratios and moment increasing rates is researched, thus presenting the fitting formula of the effective bending rigidity ratios and moment increasing ratios, which has guidance to designing shield segment.
It is introduced the definition of effective bending rigidity ratios and moment increasing rates, and it also discusses the method which can be used to determine the effective bending rigidity ratios and moment increasing rates with beam-spring modal. The effect of the joint stiffness on the effective bending rigidity ratios and moment increasing rates is researched, thus presenting the fitting formula of the effective bending rigidity ratios and moment increasing ratios, which has guidance to designing shield segment.
2006, 36(2): 50-53.
doi: 10.13204/j.gyjz200602015
Abstract:
A new method bas ed on support vector machine for vertical ultimate bearing capacity of s ingle pile is presented. SVM algorithm is bas ed on statistical theory and avoids the blindness of framework designs for neural network and the problem of nonlinear optimizations, such as local optimization. Analysis of the experimental results shows that the convergence speed of support vector machine is faster and its prediction result is more accurate than that of chaos optimization_neural network.
A new method bas ed on support vector machine for vertical ultimate bearing capacity of s ingle pile is presented. SVM algorithm is bas ed on statistical theory and avoids the blindness of framework designs for neural network and the problem of nonlinear optimizations, such as local optimization. Analysis of the experimental results shows that the convergence speed of support vector machine is faster and its prediction result is more accurate than that of chaos optimization_neural network.
2006, 36(2): 54-56.
doi: 10.13204/j.gyjz200602016
Abstract:
The mechanical properties of composite foundation with rigid piles and the one with flexible piles are analyzed using FEM software ANSYS, whose load transfer modes are also studied, which are compared to that of a pile foundation. Through calculation, it is analyzed the effect of changes in shaft modulus and modulus of underlying stratum on load distribution of the shaft. The analytic results show that the load transfer mode of the composite foundation with rigid piles is fully different from that of the one with flexible piles.
The mechanical properties of composite foundation with rigid piles and the one with flexible piles are analyzed using FEM software ANSYS, whose load transfer modes are also studied, which are compared to that of a pile foundation. Through calculation, it is analyzed the effect of changes in shaft modulus and modulus of underlying stratum on load distribution of the shaft. The analytic results show that the load transfer mode of the composite foundation with rigid piles is fully different from that of the one with flexible piles.
2006, 36(2): 57-60.
doi: 10.13204/j.gyjz200602017
Abstract:
Special temperature rising system and loading system were designed. Through the centrally pullout test, it was measured that the bond- slip performance of reinforced concrete under different temperatures and different loading ways at and after high temperature. The deterioration mechanism of bond in reinforced concrete was analyzed the investigation shows that the bond strength degrades more greatly after high temperature than at high temperature, and the slippage at the ultimate bond strength is smaller than the latter. When the temperature reached a certain value at constant load, the slippage in reinforced concrete increases sharply.
Special temperature rising system and loading system were designed. Through the centrally pullout test, it was measured that the bond- slip performance of reinforced concrete under different temperatures and different loading ways at and after high temperature. The deterioration mechanism of bond in reinforced concrete was analyzed the investigation shows that the bond strength degrades more greatly after high temperature than at high temperature, and the slippage at the ultimate bond strength is smaller than the latter. When the temperature reached a certain value at constant load, the slippage in reinforced concrete increases sharply.
2006, 36(2): 61-63.
doi: 10.13204/j.gyjz200602018
Abstract:
The measured Youngc's modulus of lightweight aggregate concrete using Lytag as coarse aggregate is lower than that calculating from existing empirical formula. T hrough experiment, another empirical formula is established, which is suitable for calculating Youngc s modulus of Lytag concrete. By comparing with relevant data from domestic and foreign codes, the empirical formula is proved to be reliable.
The measured Youngc's modulus of lightweight aggregate concrete using Lytag as coarse aggregate is lower than that calculating from existing empirical formula. T hrough experiment, another empirical formula is established, which is suitable for calculating Youngc s modulus of Lytag concrete. By comparing with relevant data from domestic and foreign codes, the empirical formula is proved to be reliable.
2006, 36(2): 64-67.
doi: 10.13204/j.gyjz200602019
Abstract:
Autogenous shrinkage of concrete with different water_cement ratios was measured from 6 hours to 28 days with a new method. This measurement method adopts a type of micro_displacement sensor and the concrete is not to be touched during the test. Development of concrete compressive strength and cement hydration process were also studied under the sealed curing condition. The results show that autogenous shrinkage and early age autogenous shrinkage speed of concrete increase remarkably with the decreasing of water_cement ratio. For every concrete, the relation between autogenous shrinkage and compressive strength or cement hydration degree at early ages can be well figured by a linear equation. The lower the water_cement ratio is, the higher the autogenous shrinkage of concrete, but the lower the cement hydration ratio and chemical shrinkage of concrete is at the same ages. Therefore it is demonstrated that autogenous shrinkage and chemical shrinkage are two different physical quantities.
Autogenous shrinkage of concrete with different water_cement ratios was measured from 6 hours to 28 days with a new method. This measurement method adopts a type of micro_displacement sensor and the concrete is not to be touched during the test. Development of concrete compressive strength and cement hydration process were also studied under the sealed curing condition. The results show that autogenous shrinkage and early age autogenous shrinkage speed of concrete increase remarkably with the decreasing of water_cement ratio. For every concrete, the relation between autogenous shrinkage and compressive strength or cement hydration degree at early ages can be well figured by a linear equation. The lower the water_cement ratio is, the higher the autogenous shrinkage of concrete, but the lower the cement hydration ratio and chemical shrinkage of concrete is at the same ages. Therefore it is demonstrated that autogenous shrinkage and chemical shrinkage are two different physical quantities.
2006, 36(2): 68-71.
doi: 10.13204/j.gyjz200602020
Abstract:
Flexural behavior of the steel tube reinforced concrete member was studied by bending test of 10 specimens. The bending strength of specimens was calculated by ultimate balance method and strap method respectively. The complete momen-t curvature relationship curves of specimens were calculated by strap method. The analytical results had good agreement with the test results. Based on the test results the momen-t curvature relationship curve of steel tube reinforced concrete member can be simplified as a tr-i linear model. Equations of the model expressed with bending stiffness were proposed.
Flexural behavior of the steel tube reinforced concrete member was studied by bending test of 10 specimens. The bending strength of specimens was calculated by ultimate balance method and strap method respectively. The complete momen-t curvature relationship curves of specimens were calculated by strap method. The analytical results had good agreement with the test results. Based on the test results the momen-t curvature relationship curve of steel tube reinforced concrete member can be simplified as a tr-i linear model. Equations of the model expressed with bending stiffness were proposed.
2006, 36(2): 72-74.
doi: 10.13204/j.gyjz200602021
Abstract:
In order to meet the needs of the practical structural des ign, the iterative formula and tactics for the form finding of cable roofs are proposed. It is called as the modified force- density method. T he method is verified by s ome benchmark problems and big proj ects. Numerical examples s how that the modified method is very simple and efficient. It can be used to find the shape of various pretensioned cable roofs.
In order to meet the needs of the practical structural des ign, the iterative formula and tactics for the form finding of cable roofs are proposed. It is called as the modified force- density method. T he method is verified by s ome benchmark problems and big proj ects. Numerical examples s how that the modified method is very simple and efficient. It can be used to find the shape of various pretensioned cable roofs.
2006, 36(2): 75-78.
doi: 10.13204/j.gyjz200602022
Abstract:
In general methods of form- finding for cable and membrane structures, the connecting nodes between the tension structure and the supporting structure are regarded as fixed nodes. Displacement of these nodes on the supporting structure is not considered. In fact, the supports nodes should be regarded as elastic supports. The interaction between the tension structure and the elastic supports is considered in form- finding process. Finally, several examples are presented. Effects of the support stiffness on the form-finding results are discussed. Some helpful conclusions are given.
In general methods of form- finding for cable and membrane structures, the connecting nodes between the tension structure and the supporting structure are regarded as fixed nodes. Displacement of these nodes on the supporting structure is not considered. In fact, the supports nodes should be regarded as elastic supports. The interaction between the tension structure and the elastic supports is considered in form- finding process. Finally, several examples are presented. Effects of the support stiffness on the form-finding results are discussed. Some helpful conclusions are given.
2006, 36(2): 79-81.
doi: 10.13204/j.gyjz200602023
Abstract:
The flexible supporting system for point supported glass curtain wall is a new type of supporting system. By analyzing a monofilament cable, it is presented the conclusions that the influencing factors of the load- carrying properties of flexible supporting system include the initial prestress, the diameter of tension rod or cable, the rise ratio and the height of the structure etc. These can provide a theoretical basis for the researchers later or the designers to study the forced properties of flexible supports.
The flexible supporting system for point supported glass curtain wall is a new type of supporting system. By analyzing a monofilament cable, it is presented the conclusions that the influencing factors of the load- carrying properties of flexible supporting system include the initial prestress, the diameter of tension rod or cable, the rise ratio and the height of the structure etc. These can provide a theoretical basis for the researchers later or the designers to study the forced properties of flexible supports.
2006, 36(2): 82-84.
doi: 10.13204/j.gyjz200602024
Abstract:
For an arched corrugated metal roof, the light dead weight and the great horizontal force from the skewback will lead to a larger eccentricity of the foundation and the larger bending and shearing forces of the support structure. It is introduced the design of the foundation of the arch falling to the ground and supported by the frame and the influence factors on the eccentricity in design ofthe practical project. The problem of bending and shearing resistance of the brick of the arch structure supported by the masonry is also introduced. Suggestions on its design method are also proposed.
For an arched corrugated metal roof, the light dead weight and the great horizontal force from the skewback will lead to a larger eccentricity of the foundation and the larger bending and shearing forces of the support structure. It is introduced the design of the foundation of the arch falling to the ground and supported by the frame and the influence factors on the eccentricity in design ofthe practical project. The problem of bending and shearing resistance of the brick of the arch structure supported by the masonry is also introduced. Suggestions on its design method are also proposed.
2006, 36(2): 85-87.
doi: 10.13204/j.gyjz200602025
Abstract:
The paper gives out the condition of yielding first for the tension steel bar in the balanced failure of SRC column. The limit value formulae of axial compression ratio for SRC column are derived including to bend around strong axis and weak axis of H- shaped steel section. Based on these formulae, the paper puts forward the limit value formula of ax ial compression ratio of the cross steel section.
The paper gives out the condition of yielding first for the tension steel bar in the balanced failure of SRC column. The limit value formulae of axial compression ratio for SRC column are derived including to bend around strong axis and weak axis of H- shaped steel section. Based on these formulae, the paper puts forward the limit value formula of ax ial compression ratio of the cross steel section.
2006, 36(2): 88-89.
doi: 10.13204/j.gyjz200602026
Abstract:
Based on the modification of the designing method of mix proportion of ordinary concrete in Specification for Mix Proportion Design of Ordinary Concrete ( JGJ 55 - 2000), it is provided the experience in mix proportion design of ordinary concrete, which s implifies the computational process .
Based on the modification of the designing method of mix proportion of ordinary concrete in Specification for Mix Proportion Design of Ordinary Concrete ( JGJ 55 - 2000), it is provided the experience in mix proportion design of ordinary concrete, which s implifies the computational process .
2006, 36(2): 90-93.
doi: 10.13204/j.gyjz200602027
Abstract:
It is evaluated the mechanical behavior of carbon fiber reinforced polymer for strengthening concrete structures and an estimating model is built to estimate the size and the test results of s pecimens.
It is evaluated the mechanical behavior of carbon fiber reinforced polymer for strengthening concrete structures and an estimating model is built to estimate the size and the test results of s pecimens.
2006, 36(2): 94-97.
doi: 10.13204/j.gyjz200602028
Abstract:
During the process of strenthening and retrofitting, a new type prestressed concrete structure with the same tendons, parts of them were existed in the concrete but others were existed as external, is introduced to retrofit the building with a big story hight to more story building. At the first, the general problem in the process of retrofitting such structure was analyzed, then the novel concept was offered and its characteristic was also presented. The methods to calculate the loss of prestressing of the same tendons were given. Then the methods of the ultimate bearing capacity and the limit state of use were also given. At last, an application example was introduced, which proves such methods effective, feasible, and worthwhile wide application.
During the process of strenthening and retrofitting, a new type prestressed concrete structure with the same tendons, parts of them were existed in the concrete but others were existed as external, is introduced to retrofit the building with a big story hight to more story building. At the first, the general problem in the process of retrofitting such structure was analyzed, then the novel concept was offered and its characteristic was also presented. The methods to calculate the loss of prestressing of the same tendons were given. Then the methods of the ultimate bearing capacity and the limit state of use were also given. At last, an application example was introduced, which proves such methods effective, feasible, and worthwhile wide application.
2006, 36(2): 98-100.
doi: 10.13204/j.gyjz200602029
Abstract:
The anchorage performance of double adhesive anchors for RC structures in reinforcement and reconstruction engineering is studied systematically by experiments. The effects of various diameter anchors and various depths and various spacing on the anchorage performance are taken into account. Some important conclusions are obtained. The results show that when the anchorage depth is 15d and the net anchorage spacing is greater than 80mm, the anchorage performance is similar to that of the single anchor. When the net anchorage space is less than 80mm, the 11%～17% discount of single anchorc's anchorage performance should be taken into account. The conclusions can provide some references to the design of anchor groups.
The anchorage performance of double adhesive anchors for RC structures in reinforcement and reconstruction engineering is studied systematically by experiments. The effects of various diameter anchors and various depths and various spacing on the anchorage performance are taken into account. Some important conclusions are obtained. The results show that when the anchorage depth is 15d and the net anchorage spacing is greater than 80mm, the anchorage performance is similar to that of the single anchor. When the net anchorage space is less than 80mm, the 11%～17% discount of single anchorc's anchorage performance should be taken into account. The conclusions can provide some references to the design of anchor groups.
2006, 36(2): 101-102.
doi: 10.13204/j.gyjz200602030
Abstract:
Our country has entered the aging society in the 21st century,so it is urgent to improve inhabitation environmental quality of the old people.Based on the physiological and psychological characteristics of old people,it is proposed several questions that merit attention in the design of living environment for old people.
Our country has entered the aging society in the 21st century,so it is urgent to improve inhabitation environmental quality of the old people.Based on the physiological and psychological characteristics of old people,it is proposed several questions that merit attention in the design of living environment for old people.
