资源类型

期刊论文 121

年份

2023 11

2022 11

2021 13

2020 5

2019 4

2018 3

2017 10

2016 2

2015 3

2014 4

2013 6

2012 8

2011 3

2010 4

2009 9

2008 7

2007 2

2006 3

2005 1

2004 1

展开 ︾

关键词

桥面铺装 3

三点弯曲梁 2

压力容器技术 2

双层辉光离子渗金属 2

双库协同机制 2

双目标渐进法 2

抑爆抗爆 2

生态文明发展水平 2

肠道菌群 2

12相整流 1

CBC-MAC模式 1

CCM模式 1

CTR模式 1

Cuk矩阵变换器 1

Maradbcm算法 1

PMAC模式 1

S-57 1

Web服务安全 1

丁酸 1

展开 ︾

检索范围:

排序: 展示方式:

Mechanical design and analysis of a novel variable stiffness actuator with symmetrical pivot adjustment

《机械工程前沿(英文)》 2021年 第16卷 第4期   页码 711-725 doi: 10.1007/s11465-021-0647-1

摘要: The safety of human–robot interaction is an essential requirement for designing collaborative robotics. Thus, this paper aims to design a novel variable stiffness actuator (VSA) that can provide safer physical human–robot interaction for collaborative robotics. VSA follows the idea of modular design, mainly including a variable stiffness module and a drive module. The variable stiffness module transmits the motion from the drive module in a roundabout manner, making the modularization of VSA possible. As the key component of the variable stiffness module, a stiffness adjustment mechanism with a symmetrical structure is applied to change the positions of a pair of pivots in two levers linearly and simultaneously, which can eliminate the additional bending moment caused by the asymmetric structure. The design of the double-deck grooves in the lever allows the pivot to move freely in the groove, avoiding the geometric constraint between the parts. Consequently, the VSA stiffness can change from zero to infinity as the pivot moves from one end of the groove to the other. To facilitate building a manipulator in the future, an expandable electrical system with a distributed structure is also proposed. Stiffness calibration and control experiments are performed to evaluate the physical performance of the designed VSA. Experiment results show that the VSA stiffness is close to the theoretical design stiffness. Furthermore, the VSA with a proportional–derivative feedback plus feedforward controller exhibits a fast response for stiffness regulation and a good performance for position tracking.

关键词: variable stiffness actuator     variable stiffness module     drive module     symmetrical structure     double-deck grooves     expandable electrical system    

A method for examining the seismic performance of steel arch deck bridges

Cheng-Yu LIANG, Airong CHEN,

《结构与土木工程前沿(英文)》 2010年 第4卷 第3期   页码 311-320 doi: 10.1007/s11709-010-0080-8

摘要: To examine the seismic resistance performance of a steel arch bridge during a strong earthquake, an approach is proposed in this paper to determine the ultimate strain of an arch rib using the static elasto-plastic large deformation theory. A steel fixed-end deck arch bridge with a span length of 200 m was used as an example in this study. The ultimate strain of the arch rib was calculated using the elasto-plastic finite element model. The seismic responses of the arch bridge exposed to strong earthquakes in two and three directions were also simulated. Moreover, the effect of earthquake motion in the lateral direction on the elasto-plastic earthquake response was discussed, and the seismic resistance of the structure was analyzed. The results show that steel arch bridges have preferable seismic resistance under strong earthquake conditions. While lateral earthquake motion has some influence on the damage to an arch bridge, it has little effect on the displacement, axial force, and bending moment responses of the arch rib. It is feasible to examine the seismic performance of the arch bridge by ascertaining the out-of-plane and in-plane earthquake responses of the bridge.

关键词: seismic performance     earthquake damage     steel deck arch bridge    

Parametric equations for notch stress concentration factors of rib–deck welds under bending loading

《结构与土木工程前沿(英文)》 2021年 第15卷 第3期   页码 595-608 doi: 10.1007/s11709-021-0720-1

摘要: The effective notch stress approach for evaluating the fatigue strength of rib–deck welds requires notch stress concentration factors obtained from complex finite element analysis. To improve the efficiency of the approach, the notch stress concentration factors for three typical fatigue-cracking modes (i.e., root–toe, root–deck, and toe–deck cracking modes) were thoroughly investigated in this study. First, we developed a model for investigating the effective notch stress in rib–deck welds. Then, we performed a parametric analysis to investigate the effects of multiple geometric parameters of a rib–deck weld on the notch stress concentration factors. On this basis, the multiple linear stepwise regression analysis was performed to obtain the optimal regression functions for predicting the notch stress concentration factors. Finally, we employed the proposed formulas in a case study. The notch stress concentration factors estimated from the developed formulas show agree well with the finite element analysis results. The results of the case study demonstrate the feasibility and reliability of the proposed formulas. It also shows that the fatigue design curve of FAT225 seems to be conservative for evaluating the fatigue strength of rib–deck welds.

关键词: notch stress concentration factor     rib–deck weld     parametric analysis     regression analysis     parametric equation    

Performance of steel bridge deck pavement structure with ultra high performance concrete based on resin

《结构与土木工程前沿(英文)》 2021年 第15卷 第4期   页码 895-904 doi: 10.1007/s11709-021-0759-z

摘要: This research investigated a pavement system on steel bridge decks that use epoxy resin (EP) bonded ultra-high performance concrete (UHPC). Through FEM analysis and static and dynamic bending fatigue tests of the composite structure, the influences of the interface of the pavement layer, reinforcement, and different paving materials on the structural performance were compared and analyzed. The results show that the resin bonded UHPC pavement structure can reduce the weld strain in the steel plate by about 32% and the relative deflection between ribs by about 52% under standard axial load conditions compared to traditional pavements. The EP bonding layer can nearly double the drawing strength of the pavement interface from 1.3 MPa, and improve the bending resistance of the UHPC structure on steel bridge decks by about 50%; the bending resistance of reinforced UHPC structures is twice that of unreinforced UHPC structure, and the dynamic deflection of the UHPC pavement structure increases exponentially with increasing fatigue load. The fatigue life is about 1.2 × 107 cycles under a fixed force of 9 kN and a dynamic deflection of 0.35 mm, which meets the requirements for fatigue performance of pavements on steel bridge decks under traffic conditions of large flow and heavy load.

关键词: steel bridge deck pavement     ultra-high-performance concrete     epoxy resin     composite structure     bending fatigue performance    

Feasibility of crack free reinforced concrete bridge deck from materials composition perspective: a state

Mahdi AREZOUMANDI

《结构与土木工程前沿(英文)》 2015年 第9卷 第1期   页码 91-103 doi: 10.1007/s11709-015-0274-1

摘要: Early age cracking on bridge deck has been the subject of many studies for years. Cracking is a major concern because it leads to premature deterioration of structures. Millions of dollars spent to repair the cracked bridge decks each year. To design an appropriate mixture for crack free bridge deck, it is important to study previous researches. This paper presents a comprehensive literature review of the performance of different materials compositions as well as methods have been used to reduce and control bridge deck cracks. Different material compositions and methods are discussed in terms of their performances as well as advantages and disadvantages.

关键词: bridge deck     crack     fiber     shrinkage     shrinkage reducing admixture    

Fatigue evaluation of steel-concrete composite deck in steel truss bridge——A case study

Huating CHEN; Xianwei ZHAN; Xiufu ZHU; Wenxue ZHANG

《结构与土木工程前沿(英文)》 2022年 第16卷 第10期   页码 1336-1350 doi: 10.1007/s11709-022-0852-y

摘要: An innovative composite deck system has recently been proposed for improved structural performance. To study the fatigue behavior of a steel-concrete composite bridge deck, we took a newly-constructed rail-cum-road steel truss bridge as a case study. The transverse stress history of the bridge deck near the main truss under the action of a standard fatigue vehicle was calculated using finite element analysis. Due to the fact that fatigue provision remains unavailable in the governing code of highway concrete bridges in China, a preliminary fatigue evaluation was conducted according to the fib Model Code. The results indicate that flexural failure of the bridge deck in the transverse negative bending moment region is the controlling fatigue failure mode. The fatigue life associated with the fatigue fracture of steel reinforcement is 56 years. However, while the top surface of the bridge deck concrete near the truss cracks after just six years, the bridge deck performs with fatigue cracks during most of its design service life. Although fatigue capacity is acceptable under design situations, overloading or understrength may increase its risk of failure. The method presented in this work can be applied to similar bridges for preliminary fatigue assessment.

关键词: Fatigue assessment     composite bridge deck     rail-cum-road bridge     fatigue stress analysis     Model Code    

Bending performance of composite bridge deck with T-shaped ribs

Qingtian SU, Changyuan DAI, Xu JIANG

《结构与土木工程前沿(英文)》 2019年 第13卷 第4期   页码 990-997 doi: 10.1007/s11709-019-0532-8

摘要: This paper proposes a new type of steel-concrete composite deck, which is composed of orthotropic steel deck (OSD) with T-shaped ribs, concrete plate and studs connecting OSD and concrete plate. The OSD can act as framework for concrete plate and contribute to load bearing capacity at the same time, which could save construction time. Compared with conventional OSD system, this new type of composite bridge deck can also improve fatigue performance. Considering that this type of composite deck is not yet applied in practical engineering and its mechanical performance is not revealed in previous literatures, two full-scale specimens were designed and manufactured in this research. The mechanical performance, particularly, bending capacity in positive and negative region was carefully tested and analyzed. The load-deflection curve, load-slip relation, strain distribution in concrete and steel were obtained. The test results showed that the plastic performance of this kind of composite bridge deck was satisfying and the bending capacity was high.

关键词: bending performance     composite bridge deck     T-shaped steel ribs    

Experimental study of aerodynamic interference effects on aerostatic coefficients of twin deck bridges

Zhiwen LIU , Zhengqing CHEN , Gao LIU , Xinpeng SHAO ,

《结构与土木工程前沿(英文)》 2009年 第3卷 第3期   页码 292-298 doi: 10.1007/s11709-009-0048-8

摘要: The aerodynamic interference effects on aerostatic coefficients of twin deck bridges with large span were investigated in detail by means of wind tunnel test. The distances between the twin decks and wind attack angles were changed during the wind tunnel test to study the effects on aerodynamic interferences of aerostatic coefficients of twin decks. The research results have shown that the drag coefficients of the leeward deck are much smaller than that of a single leeward deck. The drag coefficients of a windward deck decrease slightly compared with that of a single deck. The lift and torque coefficients of windward and leeward decks are also affected slightly by the aerodynamic interference of twin decks. And the aerodynamic interference effects on lift and torque coefficients of twin decks can be neglected.

关键词: twin decks     aerodynamic interference effects     aerostatic coefficients     wind tunnel test    

Experimental measurement of double-K fracture parameters of concrete with small-size aggregates

ZHANG Xiufang, XU Shilang, ZHENG Shuang

《结构与土木工程前沿(英文)》 2007年 第1卷 第4期   页码 448-457 doi: 10.1007/s11709-007-0061-8

摘要: The double- fracture model can well describe the development of cracks undergoing during the entire fracture process in concrete. Therefore, it has been selected as the theoretical basis of the Norm for fracture test of

关键词: development     concrete     theoretical     double- fracture    

桥面铺装病害检测技术研究

郭成超,许朋飞,崔璨

《中国工程科学》 2017年 第19卷 第6期   页码 38-43 doi: 10.15302/J-SSCAE-2017.06.006

摘要:

在桥梁的全生命周期中,桥面板是最容易出现病害的部分。桥面铺装层常常由于施工方法选择不当、混凝土老化、钢筋锈蚀等原因产生各种病害,这对桥梁结构、使用性能都会造成不利影响,因此有必要对相关病害进行检测,并对桥面质量做出相关评价。本文介绍了国内外四种主要无损检测方法(半电池电位法、探地雷达法、冲击回波法、红外热成像法)的工作原理以及相应的检测设备,利用其中一种或几种方法能准确评估桥面板的恶化情况,对桥面板状况进行快速、无损检测,为实现桥面铺装的准确检测提供技术支持,从而减少结构病害,延长桥梁的使用寿命。

关键词: 桥面铺装     病害     无损检测    

Numerical study of thermal characteristics of double skin facade system with middle shade

Shaoning LIU, Xiangfei KONG, Hua YANG, Minchao FAN, Xin ZHAN

《能源前沿(英文)》 2021年 第15卷 第1期   页码 222-234 doi: 10.1007/s11708-017-0480-8

摘要: Architectural shade is an effective method for improving building energy efficiency. A new shade combined with the double skin façade (DSF) system, called middle shade (MS), was introduced and developed for buildings. In this paper, a 3D dynamic simulation was conducted to analyze the influence of MS combined with DSF on the indoor thermal characteristics. The research on MS for DSF involves the temperature, the ventilation rate, the velocity distribution of the air flow duct, and the indoor temperature. The results show that the angle and position of the shade in the three seasons are different, and different conditions effectively enhance the indoor thermal characteristics. In summer, the appearance of MS in DSF makes the indoor temperature significantly lower. The indoor temperature is obviously lower than that of the air flow duct, and the temperature of the air flow duct is less affected by MS. The influence of the position of blinds on indoor temperature and ventilation rate is greater than the influence of the angle of blinds. According to the climate characteristics of winter and transition season, in winter, early spring, and late autumn, the indoor temperature decreases with the increase of the position of blinds at daytime, but the opposite is true at night. The results found in this paper can provide reference for the design and use of MS combined with DSF in hot summer and cold winter zone.

关键词: middle shade     position     thermal characteristics     double skin facade    

复合浇筑式钢桥面铺装车辙评估模型研究

章登精

《中国工程科学》 2013年 第15卷 第8期   页码 63-69

摘要:

根据南京长江第四大桥钢桥面铺装试验研究成果,对复合浇筑式沥青混合料性能进行了分析研究,通过系统分析动稳定度与温度、汽车轮载、车速及行车道间的关系,结合南京地区汽车超载情况的研究,提出并建立了复合浇筑式钢桥面铺装的车辙评估模型。

关键词: 复合浇筑式     钢桥面铺装     动态模量     当量轮次     车辙评估模型    

Moment-curvature relationship of FRP-concrete-steel double-skin tubular members

Mingxue LIU, Jiaru QIAN

《结构与土木工程前沿(英文)》 2009年 第3卷 第1期   页码 25-31 doi: 10.1007/s11709-009-0012-7

摘要: Tests were conducted on 3 specimens to study the flexural behavior of fiber reinforced polymer (FRP)-concrete-steel double-skin tubular members (DSTMs). The strip method was used to calculate the section moment-curvature curves of the 3 specimens and 12 models. A theoretical formula is presented for the flexural strength of DSTMs. The test results show that the tension zone of the specimen FRP tubes was in hoop compression while the compression zone was in hoop tension. The load-carrying capacity did not decrease even when the mid-span deflection reached about 1/24 of the span length. The tests, simulation and theoretical analysis resulted in a simplified formula for the flexural strength of DSTMs and a tri-linear moment-curvature model was expressed as a function of the section bending stiffness for DSTMs.

关键词: fiber reinforced polymer (FRP)     concrete     steel     double-skin tubular members (DSTMs)     moment-curvature curve     flexural strength    

Enhancement of distillate output of double basin solar still with vacuum tubes

Hitesh N PANCHAL, P K SHAH

《能源前沿(英文)》 2014年 第8卷 第1期   页码 101-109 doi: 10.1007/s11708-014-0299-5

摘要: The latent heat of condensation is lost to the atmosphere; hence it is not utilized to increase distillate output of single basin solar stills. This difficulty was overcome by attaching an additional basin to the main basin. The performance of the double basin solar still was also increased by attaching vacuum tubes to the lower basin; hence the lower basin possessed a higher temperature throughout the day. The latent heat of condensation of the bottom basin was also utilized to increase distillate. But the distillate output of the top basin was even lower compared with that of the bottom basin. This paper proposed a novel approach to increase the distillate output of the double basin solar still attached with vacuum tubes by introducing different sensible energy storage materials like pebbles, black granite gravel and calcium stones to increase the basin area. Experiments were conducted in climate conditions of Mehsana (23.6000° N, 72.4000° E) Gujarat from April to September 2013 with a constant water depth of 2 cm in the top basin with and without the use of basin materials. The results showed that the distillate output of basin material with calcium stones is greater (74%) compared with that of black granite gravel and pebbles. The integration of vacuum tubes with solar still greatly increases the distillate output of the solar still by providing hot water at the lower basin.

关键词: double basin solar still     calcium stones     pebbles     granite gravel     distillate output    

Aerodynamic interference effects and mitigation measures on vortex-induced vibrations of two adjacent cable-stayed bridges

Xiaoliang MENG, Ledong ZHU, Zhenshan GUO

《结构与土木工程前沿(英文)》 2011年 第5卷 第4期   页码 510-517 doi: 10.1007/s11709-011-0129-3

摘要: By examining the two neighboring Haihe Bridges with semi- and full-closed bridge decks, the aerodynamic interference between the two decks on the vortex-induced vibration (VIV) and the corresponding aerodynamic mitigation measures are investigated via a series of wind tunnel tests with a spring-suspended sectional model aided with computational fluid dynamics (CFD) method. The results show that the VIV responses of both bridges can be significantly affected by the aerodynamic interference and that the extent of the influence varies with the shapes of the windward and leeward decks. The VIV amplitudes of the windward bridge are often fairly close to those of the single bridge. However, those of the leeward bridge are magnified substantially by aerodynamic interference if the same structural and aerodynamic configurations are adopted for the two bridges. Otherwise, the VIV responses are not significantly increased and may even be reduced by the aerodynamic interference if different configurations are employed for the two bridges. Furthermore, an effective combined measure of adding wind barriers and sharpening the wind fairing noses of the two box decks is presented for mitigating both the vertical and torsional VIV responses of the windward and leeward bridges.

关键词: separated parallel decks     vortex-induced vibration     aerodynamic interference     aerodynamic mitigation measure     semi-closed box deck     full-closed box deck    

标题 作者 时间 类型 操作

Mechanical design and analysis of a novel variable stiffness actuator with symmetrical pivot adjustment

期刊论文

A method for examining the seismic performance of steel arch deck bridges

Cheng-Yu LIANG, Airong CHEN,

期刊论文

Parametric equations for notch stress concentration factors of rib–deck welds under bending loading

期刊论文

Performance of steel bridge deck pavement structure with ultra high performance concrete based on resin

期刊论文

Feasibility of crack free reinforced concrete bridge deck from materials composition perspective: a state

Mahdi AREZOUMANDI

期刊论文

Fatigue evaluation of steel-concrete composite deck in steel truss bridge——A case study

Huating CHEN; Xianwei ZHAN; Xiufu ZHU; Wenxue ZHANG

期刊论文

Bending performance of composite bridge deck with T-shaped ribs

Qingtian SU, Changyuan DAI, Xu JIANG

期刊论文

Experimental study of aerodynamic interference effects on aerostatic coefficients of twin deck bridges

Zhiwen LIU , Zhengqing CHEN , Gao LIU , Xinpeng SHAO ,

期刊论文

Experimental measurement of double-K fracture parameters of concrete with small-size aggregates

ZHANG Xiufang, XU Shilang, ZHENG Shuang

期刊论文

桥面铺装病害检测技术研究

郭成超,许朋飞,崔璨

期刊论文

Numerical study of thermal characteristics of double skin facade system with middle shade

Shaoning LIU, Xiangfei KONG, Hua YANG, Minchao FAN, Xin ZHAN

期刊论文

复合浇筑式钢桥面铺装车辙评估模型研究

章登精

期刊论文

Moment-curvature relationship of FRP-concrete-steel double-skin tubular members

Mingxue LIU, Jiaru QIAN

期刊论文

Enhancement of distillate output of double basin solar still with vacuum tubes

Hitesh N PANCHAL, P K SHAH

期刊论文

Aerodynamic interference effects and mitigation measures on vortex-induced vibrations of two adjacent cable-stayed bridges

Xiaoliang MENG, Ledong ZHU, Zhenshan GUO

期刊论文