Steady state Heat Transfer Performance of Domestic Light frame Wood Wall

Steady state heat transfer performance is an important indicator for wood wall to assess its energy efficiency performance. Based on the introduction of foreign advanced technology of wood residence, 13 different wall specimens were manufactured using domestic materials in this study, and the effective heat transfer coefficient were measured by hot box heat flow meter test method. With the results from theoretical calculation, it was found that the effective heat transfer coefficient of walls were between 0.226～0.529 W/(m2· K). The thermal level was IIt for specimen 1,2,3, and 6, and level It was for the others, which could be appropriate for the severe cold areas and meet the requirements of 65% Energy efficiency standard in China. The calculation results were in good agreement with the measured ones.     

Hysteretic Behavior of Composite Deep Beam Infilled Steel Frame

The Quasi static tests of one steel frame and two the composite deep beams infilled steel frames were carried out. The effects of the deep beams on the load capacity, ductility, hysteretic property and energy dissipation of pure steel structure were analyzed. It is found that the hysteresis curve is a straight line with the constant of the stiffness at the beginning and without residual deformation. And the hysteresis curve of specimen was full after yielding, and the skeleton curves had a clear plastic flow phase with triple linear. The lateral drifts of the beam specimens at failure were 1/25 and 1/22. The composite deep beams enhance the initial stiffness, yield load and maximum load bearing capacity of steel frame. Therefore, seismic performance of the composite deep beams is better.     

Experimental Analysis of Fire Resistant Performance of Concrete Frame with Damage Caused by Weak Earthquake

Two monolayer concrete frames with the same reinforcement, KJ1 and KJ2, were designed. KJ1 was designed to simulate low cyclic reversed loading test under weak earthquake. Besides, the fire response test, including temperature rising and lowing, was made by fixing the axial compression ratio of the column. For KJ2, the fire response test at the fixed axial compression ratio was made. The deformation response of the concrete frames in fire was studied. Comparative analysis of the apparent phenomenon, temperature curves, bearing capacity change of the frames were made based on the test results of KJ1 and KJ2. According to the simplified temperature distribution, the ultimate bearing capacity of the column under the high temperature was preliminarily determined. It is illustrated that the calculation results and finally test phenomenon are consistent according to the simplified section.     

The Effect of Slabs on the Failure Mode of Reinforced Concrete Frame Structures

A majority of reinforced concrete frame structure failure patterns resulting from the May 12, 2008 earthquake in Wenchuan County, P. R. China were analyzed. It was found that the main failure mode of frame works was “strong beam, weak column”, which conflicts with the design criteria of “strong column, weak beam”. The cause of this failure pattern was analyzed. A new concept is put forward that should be considered in design work. The over strength caused by slabs connected monolithically to the beams is analyzed. The joint types, transverse beam stiffness and lateral drift influence the reinforcing effect of the sla, Moreover, a reinforced concrete frame model was simulated using the program ABAQUS. The slab reinforcement stress distributions at different lateral drifts were analyzed and the effective flange width value proposed.     

Experimental Analysis on Energy Dissipation Mechanism and Seismic Performance of Steel Truss Coupling Beam-Coupled Shear Wall Structure

Pseudo-dynamic tests and low cyclic reversed loading tests on two-floor coupled shear wall planar structures were conducted, and one is arranged with two steel truss coupling beams, the other is arranged with a steel coupling beam and a RC coupling beam. The shear walls’ seismic response under different earthquake intensity was deliberated, Their failure mechanism, bearing capacity, hysteretic ductility, energy dissipation mechanism, and stiffness and strength degradation mechanism were analyzed as well. The results show that the shear wall with two steel truss coupling beams has reasonable stiffness distribution. Its energy dissipation mechanism, stiffness and strength degradation mechanism can fulfill the demands of coupled shear wall’s seismic design: under rare earthquake, it can maintain good bearing capacity and stiffness, and keep restraining the walls. Its seismic performance is superior to RC coupling beams-coupled shear wall system.     

Experimental Analysis of Time-dependent Shear Behavior on Stud Connectors

With regard to the long span continuous composite beams, the early composite shear stud strength at the joint surface between the steel girder and concrete slab at different concrete ages should be considered while the concrete slabs are casted by phases in construction stage. In this study, the push-out test of stud shear connectors were conduced at different concrete ages. Meanwhile, the change law of the ultimate shear strength, ultimate slip deformation, design shear strength, and shear stiffness of the stud shear connectors with concrete ages were analyzed, and the corresponding time-dependent calculation equations were presented. The results include that the main failure modes of stud shear connectors are the concrete slab splitting failure before 3-days concrete age. The load-slip laws of stud shear connectors at different concrete ages are basically the same, however, the shear strength and stiffness all increase with the concrete ages prolonging, and the increase degree is faster at early ages, but slower at later ages, which indicates that the early composite shear stud strength at the joint surface of composite beams should not be neglected.     

Numerical Simulation Analysis on Ductility Performance of High Strength RC Frame Structure

High-strength concrete has been widely used in civil structures for advantages of higher-strength, earlier curing strength and smaller deformation in applications. However, relatively weak ductility in structures in seismic zones prevented it from further application. The ductility of the structure can be improved by reinforcing reasonably rebars in correct details. A high strength RC frame model with twelve floors and two bays is numerically analyzed by using DRAIN-2DX program. It was shown that this worked fairly well in simulation of the process of structural damage and energy dissipation capacity. It also showed that this kind of frame structure has good ductility and dissipation capacity as well as great seismic performance. The proposed method can be applied in high-strength concrete structures in seismic zone.     

Experimental Analysis of Vibration Behavior for Large-span Underground Structure

In this paper, a shaking table test for large-span underground structure is introduced. Based on the test, the frequency of inherent vibration, damping ratio and the dynamic response of the structure are studied. The response of the underground structure for vertical seismic excitation is studied as a key point. With the different imbedding depth, the influence of interaction of soil and structure on the earthquake-resistant capacity of the underground structure is discussed.     

Experimental Study on a Prestressed Frame of Two Spans Under Unsymmetric Load

By the experimental study on a full-dimensioned prestressed frame of two spans, the relative factors are analyzed such as relative height of equivalent compression zone in critical section, secondary moment, ratio of beam rigidity to column and development of cracks in the top of columns etc., which influence the moment distribution of the post-tensioned prestressed concrete frame from the side of internal force redistribution. It is believed that that the factors of relative height of concrete equivalent compression zone and secondary moment influence the moment modulation in most degree, and ratio of column rigidity to beam also plays a part in the moment modulation to some extent. Second, the plastic joints of frame with excessive spans exit in the span which endure the whole load, at last the whole frame is destroyed because of the destruction of the loading frame, the influence to the non-loading span is little.     

Finite Element Analysis of the Contact Stress of the Rotary Hinge in the Rigid Frame Arch Bridge Constructed in a Vertically Downward Rotating Manner

Rotary hinges are temporary joints connecting arch ribs with the abutments of rigid frame arch bridges during the vertically downward rotating construction process.We probed the mechanical properties of a rotary hinge.Its stress distribution was simulated in contact FEM during the vertically downward rotating construction of a rigid frame arch bridge.The results show that nearly the entire structure of the rotary hinge is in a low-stress state with only a minor area in a high-stress state.By strengthening some local structures,rotary hinge construction security could be satisfied by its mechanical properties during vertically downward rotating construction.     

Analysis on the Force-Transferring Mechanism of the Earthquake-Resistant Reinforced Concrete Frame Joints

On the basis of a summary of achievements from a large quantity of experimental studies both at home and abroad, in combination with the authors'experience in the experimental works on the reinforced concrete frame joints, their force-transferring characteristics are fully studied. The important fact that there is also a confined mechanism besides the inclined compressive strut and the truss mechanisms,is clearly pointed out. The influences of the three mechanisms upon the mechanical behaviors of the joint core concrete, the transverse and the vertical reinforcements,as well as upon the failure characteristics of the joint are also explored. Mechanical behaviors of the inclined concrete compressive strut and the factors causing its failure are specially discussed. These analyses provide theoretical bases for establishing more rational earthquake-resistant design criterion for reinforced concrete frame joints.     

Nonlinear Analysis on the Ultimate Strength of the Slender Frame Columns for Chongqing Grand Theatre

To investigate the influence of accidental eccentricity, embedded-in foundation condition and other factors on the ultimate strength of the RC slender frame column for Chongqing Grand Theatre, a nonlinear analysis of the local frame composed of peripheral     

Seismic Behaviour of Multi Story Brick Building with Frame Shear Wall in the Two Botton Floors

A shear vibrational model applied assemblage of multiple particles is proposed for the seismic response analysis of masonry building with R/C frame wall in the two bottom floors.On the basis of analyses,some problems are discussed,these mainly are:dynamic properties,main factors that have influence on seismic behavior,earthquake resistant reliability of this building under strong earthquake and the rational ratios of lateral rigidity.[WT5HZ]     

Experimental Analysis on Seismic Performance of Steel Bracing Bound-Column Component

The seismic resistant performance and failure mechanism of the steel bracing Bound-Column were analyzed with tests and the finite element method. Two-story steel bracing Bound-Column test specimen was selected. The braces adopt long leg back-back double angle. Tests were divided into three groups, including one monotonic loading test and two cyclic tests. Lateral load-bearing capacity, stiffness and hysteretic behavior of the steel bracing Bound-Column were obtained by the comparison of test results and the finite element method. Results show that the steel brace of Bound-Column contributes a lot to its load capacity and stiffness, while the external frame provides little lateral rigidity and capacity. Bound-Column failure occurs only in the steel braces, while the external frame is with no damage.     

淡干海参泡发工艺研究

为探究淡干海参泡发工艺,以烟台淡干海参为原料,通过正交试验得到最优工艺条件为：121 ℃、0.12 MPa高温高压处理20 min,全程使用蒸馏水,泡发温度4 ℃,泡发时间48 h,采用该工艺泡发的海参质量和长度分别为泡发前干海参的14.5倍和2.7倍,复水比为9.2,其硬度、弹性、适口性、持水力及营养价值均高于市面上常压煮制常温泡发的海参。该研究结果为科学、方便地食用和推广淡干海参提供了理论依据。     

木酢液对几种类型蔬菜生长调节效应的影响

大棚种植了西红柿、辣椒、大白菜、黄瓜和萝卜等6种4类蔬菜。苗期时,喷施木酢液1000倍液;定植后,采用喷施200倍液、300倍液、400倍液、500倍液、600倍液等5个浓度处理,以此来分析施用木酢液对各类蔬菜产量、根长及株高的影响。结果表明：木酢液对不同类型的蔬菜都有一定的增产作用,但效果不一,300倍液适用面较广、200倍液对不同类型蔬菜都有生理毒害效应、600倍液对蔬菜的生长长势有明显的促进作用。总体看来,适宜浓度的木酢液能促进植株生长,提高蔬菜产量。     

钢结构仿古建筑双梁柱中节点的受力机理

为研究钢结构仿古建筑双梁柱中节点的抗震性能,对4个全焊双梁柱中节点进行了水平低周反复加载试验。通过观测试件在侧向力作用下的受力过程和破坏形态,分析双梁柱中节点的受力机理。根据梁截面形式的不同,将其分为箱型截面梁与工字型截面梁2类,依据仿古建筑独特的构造特点,将各试件节点核心区划分为上、中、下3个区域。通过量测各区域内的应变大小,分析该类结构节点核心区在侧向力作用下的受理机理及破坏模式,并建立双梁柱节点的斜压杆受力模型。试验结果表明：仿古建筑双梁柱节点的破坏形式主要为沿下核心区对角线的剪切破坏,并通过理论计算分析提出一种考虑轴压比与梁截面形式的双梁柱中节点抗剪承载力修正公式。     

Experimental Research on the Seismic Behavior of the Interior Joint with High Shear - Compression Ratios in the Frame

The reversed cyclic loading tests of 5 nearly full-scale beam-column assembly specimens with high shear-compression ratio under different axial loads in reinforced concrete plane frames have been completed,which cover the shortage in the field of high shear-compression parameter among seismic joint experiments in the world.Based on relatively complete measuring and analyses of the law for the bond and slip of the beam bar through the joint,the stress of the level stirrup legs and hysteretic dissipated energy and the change of rigidity,the characteristic of shear transfer mechanisms and damage development and comprehensive seismic behavior of the assembly are proposed in this paper.It makes it possible to improve design codes and to establish relatively reasonable analytic modes and hysteretic modes in inelastic dynamic response analyses of the frame.