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Objective To investigate the status of professional identity and job satisfaction of blood transfusion physicians in clinical in Tianjin, and to analyze the influencing factors. Methods The status of professional identity and job satisfaction of physicians in Blood Transfusion Department or Blood Bank of hospitals in Tianjin was investigated and analyzed by online questionnaire survey. Results The average score of professional identity and job satisfaction was(3.96±0.46) and (3.11±0.86), respectively. Pearson analysis was used for correlation analysis, and the results showed that the dimensions of professional identity and job satisfaction were significantly positively correlated(P

The 2022 International Conference—Bamboo: A Very Sustainable Construction Material & the 3rd World Symposium on Sustainable Bio-Composite Materials and Structures—was held from November 8 to December 13, 2022. This conference was led by INBAR and INBAR Bamboo Construction Task Force and co-organized by 37 other national and international institutions. More than 80 experts from over 20 countries delivered speeches or presentations to approximately 1400 participants from 81 countries and shared the latest research and development on bamboo and timber construction with them. The conference convened global architects, engineers, forestry experts, researchers, entrepreneurs, and policy makers to present the potential uses and suitability of bamboo, timber, and other biomaterials as conventional construction materials in modern society. This paper summarizes the key deliberations and findings of the diverse research, including the state-of-practice and the means of moving the state-of-the-art forward. Further actions on training, standardization, and research were urged to be taken to promote this industry.

2021 International Online Seminar - Bamboo: A Very Sustainable Construction Material was held in November 2021. This was led by INBAR and co-organised by other 16 national and international institutions. Nineteen senior experts from 10 countries delivered presentations and shared the latest research and development on bamboo construction to approximately 900 participants from 74 countries. The seminar called upon global architects, engineers and landscape designers to rethink time-tested traditional bamboo architectural forms and related technologies, and use innovative ideas to reshape the global built environment. This paper summarizes the findings of this Seminar, highlighting that while bamboo is growingly accepted as a construction material, considerable efforts are needed to promote bamboo as a mainstream material. The state-of-practice is summarized and means of moving the state-of-the-art forward are discussed. Architects and engineers using bamboo all over the world should work together to contribute to the basic work of bamboo architecture research, standardization and industry development.

Based on ABAQUS system, the flexural behavior of the closed profiled steel sheeting‐concrete composite slab was studied. The influence of different geometric and material parameters on the bending bearing capacity and flexural rigidity of the closed profiled steel sheeting‐concrete composite slab was analyzed. And the applicability of the current Chinese codes to the calculation of the bending bearing capacity of the closed composite slab was discussed. The results showed that, the influence of slab thickness is the largest, followed by the thickness and strength of steel sheeting, and the influence of concrete strength is the smallest; the calculation of the flexural bearing capacity of the closed profiled steel sheeting‐concrete composite slab is safe and conservative in accordance with the current Chinese codes. [ABSTRACT FROM AUTHOR]

Monolayer cable net system supporting glass facades is structurally sensitive to wind excitations. At present, there are limited researches on its wind-induced vibration performance, therefore it appears imperative to understand the wind-resistant behavior of this type of cable net. The wind-induced response of the monolayer cable net subjected to fluctuating wind loads is investigated with frequency-domain method in this paper, when the cable net deforms to the balance position under the mean wind loads. Some critical factors to wind-induced response are highlighted, including participation property of the modes in the dynamic vibration, and coupling effect among modes. The response spectrum of the cable net is also intensively investigated. It is shown that the first mode dominates wind-induced response significantly in all the modes, and the modes contributing to the wind-induced responses prominently are distributed in a narrow band of low order modes. When some lower modes and coupling effects among these modes are considered, the results in frequency domain agree well with the corresponding results obtained from time domain method, which are adequate for engineering practice. The characteristics of response spectrum of the nodal displacements are similar to those of the cable forces. When the wind loads and structural parameters vary in practical ranges in engineering, the resonant component in the total response sometimes occupies larger part in the total fluctuating wind response of the cable net, while the background component dominates in the wind response more commonly. Nevertheless, the first mode makes the largest contributions, no matter the background or the resonant component dominates. DOI: 10.1061/(ASCE)0733-9399(2010)136:3(311) CE Database subject headings: Wind loads; Excitation; Vibration; Cables. Author keywords: Monolayer cable net; Wind-induced response; Frequency domain; Mode; Coupling; Response spectrum.

The pinned connection method was used to connect the large-span floor truss to the steel column in Zoucheng International Conference Center project, which played a quite important role to achieve the in-plane rotation and transfer heavy loads directly. Four specimens were tested experimentally to investigate the monotonic and cyclic behavior of this connection method, including two independent pinned connections and two assembled truss connections. The load-displacement curves, deformation development, failure mode, ductility and energy dissipation capacity were discussed in detail. Besides, the nonlinear multi-scale finite element models of the pinned and truss connections were established. The numerical simulations not only captured the global behavior and local limit states observed in tests but also revealed valuable new information that could not be directly obtained from the tests. The experimental and numerical results showed that both the pinned and truss connections had good ductility, load transfer ability and ideal rotation capacity with large safety margin, indicating these constructions could be used as references for similar projects. [ABSTRACT FROM AUTHOR]

Low yield point (LYP) steel is a kind of excellent material used in seismic structures. To get its constitutive model under cyclic loading, 20 specimens made of LYP steel SLY100 were tested under different loading systems. Monotonic characteristics, hysteretic curves, and failure modes were analyzed. Skeleton curves under cyclic loads were fitted. Parameters of combined hardening model were calibrated and verified. Then the constitutive model was applied in the numerical simulation of BRBs. It was indicated that SLY100 steel exhibited significant cyclic hardening phenomena and possessed distinguished ductility even after being subjected to cyclic loading. The Ramberg- Osgood model fit the skeleton curves well under cyclic loading with strain increasing gradually; good consistency between the stress-strain curves calculated by ABAQUS and test curves demonstrated the accuracy of the hardening parameters proposed. The finite element (FE) model of the buckling-restrained braces (BRBs) with SLY100 steel in which calibrated results were applied could simulate BRBs' performance well. [ABSTRACT FROM AUTHOR]

In order to quantitatively describe the effect of strength and stiffness degradation on seismic behaviors of steel frame, numerical models (the equivalent constitutive model considering damage and steel hysteretic constitutive model without considering damage) for predicting seismic behaviors of steel frame structures were described. Three frame models of five-floor, ten-floor and fifteen-floor frames were analyzed. Eight earthquake records were selected for time history analysis. The differences of inter-story drift ratio distribution calculated by two constitutive models were compared. The influencing laws and degrees of damage and degradation on seismic behaviors were also obtained. Finally, a prediction curve of degradation index was proposed, which could be used for damage control. Preliminary evaluation methods for seismic performance of steel frames considering damage and degradation were discussed. The analysis of the results showed that: the inter-story drift ratios of the three frames calculated by damage model were obviously larger than the results of non-damage model, showing that damage and degradation amplified the structural deformations. With the increasing of floors, the differences of inter-story drift ratio between damage model and non-damage model were gradually reduced. The weak stories of three models were located at 0.4 to 0.5 times of structural height, which should be paid more attention in design process. [ABSTRACT FROM AUTHOR]

The present investigation studies the load bearing performance of stainless steel bolted connections. The austenitic stainless steel developed in China containing approximately 17% of Cr, which could be graded as EN 1.4401, has been selected for this research. In order to study the bearing strength of stainless steel bolted connections, experimental tests on 5 specimens have been conducted. In addition, complementary finite element (FE) models, which have been validated by the test results, have been adopted to analyse the effect of the key factors for bearing strength of the stainless steel bolted connections. The key factors include end distance, thickness of connecting plate, diameter of stainless steel bolt and edge distance. According to the FEA results, the loading capacity increases with the increase of the thickness of the plate and the diameter of the bolt approximate linearly. However, the end distance and edge distance have a comparatively complicated influence on the loading capacity of the connection. Based on mathematical analysis of the experimental and FEA results, a calculation method as well as its simplified form for the bearing strength of stainless steel bolted connections has been proposed. [ABSTRACT FROM AUTHOR]

Electrostatic Precipitator draws many researches on flue gas treatment technology and very few researches on its structural design. The conventional structural design of electrostatic precipitator casing uses stiffened flat sheet as wallboard which consumes a great amount of steel. Consequently, a new structural idea was explored to optimize the conventional design which applies profiled steel sheet and locates wall beam and wall column. Optimization codes were programmed to select the optimum design with minimum steel consumption and analyze the wall structure. For the cases with varying geometry and varying load, the optimum sections of profiled steel sheet, the optimum layout of wall beams and wall columns and the overall optimum design of casing wall were found. Besides, the influences of wallboard size and load magnitude on the optimum design were investigated. Compared with the original wall structure of stiffened steel sheet, the optimized wall structure composed of profiled sheet, wall column and wall beam can save steel significantly which can be applied widely in large-scale electrostatic precipitator casing structures. [ABSTRACT FROM AUTHOR]

8 specimens of beam-to-column bolted end-plate connections with various details and welded I-shaped section columns and beams were tested under monotonic loads. Based on the specification for the end-plate connection rotation proposed, the contribution of the panel zone and the gap between the end-plate and column flange to the joint rotation have been obtained. The influences of both flush and extended types, column stiffeners, end-plate rib stiffeners, bolt sizes and end-plate thicknesses etc on the joint behaviour have been compared. The test results indicate that all these connections tested are typically semi-rigid. For the flush and extended end-plate connection, the joint rotation mainly derives from the relative deformation between the end plate and the column flange and the shearing deformation of the panel zone respectively. Using a special method to measure bolt strain, the bolt tension forces and their development and distribution have been depicted and studied, and two bolt tension force distribution models for end-plate connections using pretensioned bolts are recommended. [ABSTRACT FROM AUTHOR]

The composite slim beam has become popular throughout Europe in recent years and has also been used on some projects in China. With its steel section encased in a concrete slab, the steel-concrete composite slim beam can provide the floor construction with minimum depth and high fire resistance. However, the design method of the T-shape steel-concrete composite beam is no longer applicable to the composite slim beam with deep deck for its special construction, of which the present design models are not available but mainly depend on experiences. The elevation of the flexural stiffness and bending capacity of composite slim beams with deep deck is rather complicated, because the influences of many factors should be taken into account, such as the variable section dimensions, development of cracks and non-linear characteristics of concrete, etc. In this paper, experimental investigations have been conducted into the flexural behavior of two specimens of simply supported composite slim beam with deep deck. The emphases were laid on the bonding force on the interface between steel beam and concrete, the stress distribution of beam section, the flexural stiffness and bending capacity of the composite beams. Based on the experimental results, the reduction factor of equivalent stress distribution in concrete flange is suggested, and the calculation method of flexural stiffness and bending capacity of simply supported slim beams are proposed. [ABSTRACT FROM AUTHOR]

Study of the dynamic properties of a monolayer cable net is described in this part II of the paper. The linear vibration properties of a cable net are analyzed in the form of a lumped-mass system based on the assumption of small-amplitude vibration. The respective influence of two vital factors: geometric shape and cable pretension on the dynamic properties of cable nets at different deflected positions under load is especially focused upon. Results show that when the geometric shape has a small displacement, the displacement influence on frequencies of vibration is almost the same as that of pre-tension, otherwise, the influence of geometric shape is far greater than that of pre-tension. Dynamic tests on the cable net model mentioned in Part I were also carried out at each pre-stretching stage. The results of experiments agree well with those of finite element analysis (FEA). In addition, a modified method called ‘MML’ based on Rayleigh's approach for the calculation of fundamental frequency is put forward in this paper, since it was found that Rayleigh's approach may sometimes introduce large errors. The nonlinear dynamic properties of the cable net were also analyzed. Different from the linear vibration case, nonlinear cases are to some extent amplitude-dependent. Thus explicitly approximate formulae for the first and second nonlinear modal frequencies are derived from continuous theory assuming the cable net to act as a continuous membrane. Transient dynamic analysis using the finite element software ANSYS was carried out to validate the formulae. The results given by the formulae and those via numerical analysis agree with each other well. [ABSTRACT FROM AUTHOR]

Monolayer cable nets have been widely applied in point-supported glass facades in recent years because of transparency, light weight and flexibility of construction. In this paper, work on the static load bearing performance of this type of cable net is described through the use of finite element analysis (FEA) and tests on a 1/10-scale model of a real project in P.R. China under construction. Firstly a method of analysis inverse to the sequence of erection and much different from conventional methods, is used to model the pre-stretching of cables with the aid of FEA to provide guidelines for the tests. Cable pre-stretching proceeds by three stages, then load bearing behaviour tests on the cable net are carried out both before and after the installation of glass panels. The agreement between the pre-stretching tests and the FEA analysis indicates that the inverse analysis method is convenient in calculation, and provides useful references for the pre-stretching of similar types of cable net in practical engineering. The nonlinear relationship found between loads and displacements just indicates the nonlinear properties of flexible cable nets. Before the installation of glass panels, the structural stiffness actually increases slowly with increasing external loads, and greater initial pre-tension is more beneficial to load bearing capacity of the structure. But too large an initial pre-tension may overload the supporting structures of the cable net. The increase in cable force due to external loads is small. Nevertheless, the stiffness of the glass panels themselves make a significant contribution to the overall structural stiffness, the contribution which becomes less obvious as the stiffness of the cable net itself increases. [ABSTRACT FROM AUTHOR]

The present investigation studies the overall stability bearing capacities of stainless steel welded I-section beams. Experimental tests of 8 specimens have been conducted. In addition, complementary finite element (FE) models, which have been validated by the test results, are adopted to calculate the overall stability bearing capacities of the beams. Based on the results of FE analyses and experimental tests, as well as the comparisons of design standards for buckling reduction factor calculations of stainless steel structural components, two calculation methods for buckling reduction factors of welded I-section beams are proposed. One is the modification of Chinese code for design of steel structures, and the other is regressed by the FE analysis results. Both methods are conservative and have simple formulations for engineering design. [ABSTRACT FROM AUTHOR]