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土木工程学报 2003年第8期36卷 74-78页

作者：姜绍飞刘明倪一清高赞明沈阳建筑工程学院香港理工大学

由于概率神经网络(PNN)以贝叶斯概率方法描述测量数据,因而PNN在有噪声条件下的结构损伤检测方面,具有巨大的潜力。而PNN中高斯核函数的宽度,严重影响网络的泛化能力,本文提出了一种运用自适应PNN进行复杂结构的损伤定位研究方法,并与传... 详细信息

由于概率神经网络(PNN)以贝叶斯概率方法描述测量数据,因而PNN在有噪声条件下的结构损伤检测方面,具有巨大的潜力。而PNN中高斯核函数的宽度,严重影响网络的泛化能力,本文提出了一种运用自适应PNN进行复杂结构的损伤定位研究方法,并与传统PNN对大跨悬索桥的损伤定位进行了仿真性能比较;同时讨论了噪声程度、特征向量简化对损伤识别精度的影响。研究发现,运用自适应PNN进行损伤定位,不仅性能优于传统PNN,而且进行特征向量简化时,可以提高损伤定位的识别精度。

关键词：概率神经网络损伤定位识别精度噪声

单、双孔隙结构非饱和黏土孔隙分布变化规律试验研究

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岩土力学 2024年第2期45卷 353-363,374页

作者：张思奇裴华富谭道远朱鸿鹄大连理工大学海岸和近海工程国家重点实验室辽宁大连116024 香港理工大学土木与环境工程学系中国香港南京大学地球科学与工程学院江苏南京210023

由于孔隙分布曲线的复杂性,在非饱和过程中黏土的孔隙结构变化规律尚不明晰,这导致基于孔隙分布模型计算土-水特征曲线存在较大的误差。针对这一问题,基于干缩试验与压汞试验,对单孔与双孔结构重塑黏土在脱湿过程中孔隙分布曲线的变化... 详细信息

由于孔隙分布曲线的复杂性,在非饱和过程中黏土的孔隙结构变化规律尚不明晰,这导致基于孔隙分布模型计算土-水特征曲线存在较大的误差。针对这一问题,基于干缩试验与压汞试验,对单孔与双孔结构重塑黏土在脱湿过程中孔隙分布曲线的变化规律进行了定量分析。研究表明:在脱湿过程中孔隙分布曲线存在平移、缩放等变换。构建了t分布和双t分布函数,提取了孔隙分布曲线的自由度、峰值、峰值对应的孔隙直径作为特征参数来表征孔隙分布变化规律,发现了特征参数和土样孔隙比之间存在较好的线性关系。基于试验结果,建立了含水率-孔隙比-孔隙分布曲线关系,提出了一个考虑孔隙结构变化的重塑黏土土-水特征曲线计算框架。最后,与试验测得的土-水特征曲线进行比较,验证了所提出的计算方法的准确性。

关键词：黏土非饱和土孔隙分布曲线压汞试验土-水特征曲线干缩试验

The Novel Mechanical Property of Tongue of a Woodpecker

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Journal of Bionic engineering 2009年第3期6卷 214-218页

作者： P Zhou X Q kong C W Wu Z Chen National Key Laboratory for structural Analysis of Industrial Equipment Dalian University of Technology department of civil and Environmental {2. University of Missouri

Biomaterials such as bone,teeth,nacre and silk are known to have superior mechanical properties due to their specific nanocomposite *** we report that the woodpecker's tongue exhibits a novel strength and flexibility due to its special composite micro/*** tongue consists of a flexible cartilage-and-bone skeleton covered with a thin layer tissue of high strength and *** the interface between the cartilage-and-bone skeleton and the tissue layer,there is a hierarchical fiber-typed *** is this special design of the tongue that makes the woodpeckers efficient in catching the insects inside *** special micro/nanostructures of the woodpecker's tongue show us a potential method to enhance the interfacial connection between soft and hard material layers for bio-inspired composite system designs.

关键词： woodpeckcr hyoid cartllage multilevel structure tensile strength

SHEAR CAPACITY OF REINFORCED RECYCLED AGGREGATE CONCRETE BEAMS WITHOUT WEB REINFORCEMENT

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SHEAR CAPACITY OF REINFORCED RECYCLED AGGREGATE CONCRETE BEA...

Self-healing of microcapsule-based materials for highway construction:A review

2.d International Conference on Waste engineering and Management

作者： Jiabin LI(1 2. Jianzhuang XIAO(2. and Jian HUANG(3) (1) Institute for structural Concrete Graz university of Technology Austria (2. {2. of Building engineering Tongji university P.R china (3) Guangdong Institute of Building Science P.R china

＜正＞This paper deals with the shear capacity of reinforced recycled aggregate concrete（RAC） beam without web *** this end,related test data on this topic in the published literature were *** behaviour and failure mode of RAC beams without web reinforcements are *** influence of various factors,such as the recycled（coarse） aggregate replacement percentage,the shear span-to-depth ratio,as well as the longitudinal reinforcement ratio on the shear capacity is *** suitability of the equations used to determine the shear capacity of reinforced conventional（or natural aggregate） concrete beams in several codes,such as ACI 318,EC2.and MC2.10 as well as GB50010,is evaluated through a comparison of the predicted value and the test data for RAC *** was found that the equations in existing codes are generally not conservative for RAC beams, especially for beams with large recycled aggregate *** recommendations for the design of reinforced RAC beams without web reinforcement are proposed.

关键词：

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Journal of Traffic and Transportation engineering(English Edition) 2023年第3期10卷 368-384页

作者： Enlin Ma Xi Chen Jinxing Lai Xiangze kong Chunxia Guo School of Highway Chang'an UniversityXi'an 710064China department of civil {2. Aalto UniversityAalto 00076Finland Southwest Municipal engineering Design&Research Institute of china Chengdu 610299China department of Chemistry and Materials Science Aalto UniversityAalto 00076Finland School of Science Xi'an University of Architecture and TechnologyXi'an 710055China

Maintaining the health and reliability of civil facilities is of strategic *** highway engineering,pavement cracking impairs the road service and travel comfort level,while structure cracking can cause catastrophic ***-based self-healing materials offer solutions to auto-recovery micro-cracks and maintain {2. *** solution has become available by laboratory synthesis and proved effective in addressing the cracking problem during long-term mechanical,thermal,and hydraulic ***,full-scale applications of this technique are not prevalent,showing its potential limitations in highway *** healing in highways is a big topic,therefore,this review has two insertion points.(1)We focus on the cracking issues on two specific materials:asphalt and concrete,which account for the vast majority of all the materials used in pavement and structures in highways.(2.Instead of the laboratory studies,we pay more attention to the practical applications,the meaning of healing performance,and the adverse effects of microcapsules to the main {2. components(i.e.,tunnel lining,bridge piers and beams)and pavement in *** practical significance of self-healing materials in highway projects was discussed from the three aspects:strength,durability,and stress *** difficulty in applying this new technique is also discussed from economic *** future-proofing,a material evaluation system that fits the load condition is *** self-healing technique brings composites a chance to interact with the environment,showing high potential for contributing to the development of various types of long-lasting infrastructures.

关键词： Road engineering Self-healing material Structure cracking Micro-encapsulation Facility lifetime

Experimental Study of Aerodynamic Interference Effects on Double Thin-Walled Hollow Pier in Tandem Arrangement

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Experimental Study of Aerodynamic Interference Effects on Do...

Advances in statistical mechanics of rock masses and its engineering applications

创新、安全与可持续发展——2.11中国（西安）国际建筑科技大会

作者： Jie Wang~(1,2.a),Jinyun Zhao~(3,b) and Jianxin Liu~(2.c) 1 Key Laboratory of structural engineering and Earthquake Resistance, Xi'an Univ of Arch.& Tech.,Xi'an,Shanxi,710055,{2. 2.Wind Tunnel Laboratory,Chang'an university,Xi'an,Shanxi,710064,{2. 3 Road and Bridge department,Jilin Communications polytechnic, Changchun,Jilin,130012.{2.

Against the problem of the aerodynamic interference effects on aerostatic coefficients between parallel continuous rigid frame bridges with high-pier and long-span,the aerodynamic interference effects on aerostatic coefficients of double thin-walled hollow pier in the parallel long-span continuous rigid frame bridges were investigated in details by means of wind tunnel *** space between the two piers and wind direction angles were changed during the wind tunnel test to study the effects on aerodynamic interferences of aerostatic coefficients of twin piers. The test got aerostatic coefficients of 8 *** research results have shown that the aerodynamic interference effects on aerostatic coefficients of double thin-walled hollow pier in parallel bridges can not be *** aerodynamic interference effects on parallel bridge pier is shown mainly as follows:The tandem interval and wind direction angles are important factors affecting interference *** drag coefficient of pier downstream dropped and the drag coefficient of pier upstream changed but Not change *** are also the aerodynamic interference effects of lateral force coefficient and torque coefficient between the piers upstream and *** effects upstream are smaller and the effects downstream are larger.

关键词： Double-width parallel bridge Double thin-walled hollow pier Aerodynamic interference effects Aerostatic coefficients Wind tunnel test

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Journal of Rock Mechanics and Geotechnical engineering 2021年第1期13卷 22-45页

作者： Faquan Wu Jie Wu Han Bao Bo Li Zhigang Shan Deheng kong Shaoxing university Shaoxing312000China Rock Innovation(Zhejiang)Co. Ltd.Shaoxing312000China School of Highway Chang’an UniversityXi’an710064China Huadong engineering Co. Ltd.PowerChinaHangzhou311122China department of Geotechnical engineering College of Civil EngineeringTongji UniversityShanghai200092China

To efficiently link the continuum mechanics for rocks with the structural statistics of rock masses,a theoretical and methodological system called the statistical mechanics of rock masses(SMRM)was developed in the past three *** SMRM,equivalent continuum models of stressestrain relationship,strength and failure probability for jointed rock masses were established,which were based on the geometric probability models characterising the rock mass *** follows the statistical physics,the continuum mechanics,the fracture mechanics and the weakest link hypothesis.A general constitutive model and complete stressestrain models under compressive and shear conditions were also developed as the derivatives of the SMRM *** SMRM calculation system was then developed to provide fast and precise solutions for parameter estimations of rock masses,such as full-direction rock quality designation(RQD),elastic modulus,Coulomb compressive strength,rock mass quality rating,and Poisson’s ratio and shear *** constitutive equations involved in SMRM were integrated into a FLAC3D based numerical module to apply for engineering rock *** is also capable of analysing the complete deformation of rock masses and active reinforcement of engineering rock *** of engineering applications of SMRM were presented,including a rock mass at QBT hydropower station in northwestern china,a dam slope of Zongo II hydropower station in ***,an open-pit mine in Dexing,china,an underground powerhouse of Jinping I hydropower station in southwestern china,and a typical circular tunnel in Lanzhou-Chongqing railway,*** applications verified the reliability of the SMRM and demonstrated its applicability to broad engineering issues associated with jointed rock masses.

关键词： Statistical mechanics of rock masses(SMRM) Jointed rock mass Geometric probability model Failure probability Anisotropic constitutive model engineering parameters

基于数-物模型混合交互反馈的结构近实时震害评估理论框架

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结构工程师 2024年第1期40卷 1-10页

作者：熊青松熊海贝袁程孔庆钊同济大学土木工程防灾减灾全国重点实验室上海200092 香港理工大学土木及环境工程学系中国香港

科学合理的结构震害评估对于提升城市抗震韧性与运维智慧具有重要意义。针对韧性城市构建现阶段的实际需求与重要难题,面向“全域、动态、实时”的结构震害评估新范式,以基于数模的多模态特征融合和基于物模的多层次数值仿真模拟为理论... 详细信息

科学合理的结构震害评估对于提升城市抗震韧性与运维智慧具有重要意义。针对韧性城市构建现阶段的实际需求与重要难题,面向“全域、动态、实时”的结构震害评估新范式,以基于数模的多模态特征融合和基于物模的多层次数值仿真模拟为理论架构的两大基本要素,依托深度学习、数字孪生、数物融合等新技术,提出了基于数-物模型混合交互反馈的结构近实时震害评估理论框架,并对该框架中的主要研究内容与关键科学问题进行了详细阐述。所提出的理论架构有望提升结构震害评估的实时性与智能性,助力推进韧性城市构建以及城市系统的智慧运维。

关键词：结构震害数-物融合混合交互反馈近实时评估深度学习

Dynamic Concept of Returns to Scales and Its Characteristics on Production Frontier in Intersection Form

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Acta Mathematicae Applicatae Sinica 2011年第3期27卷 355-366页

作者： Quan-ling Wei hong Yan Institute of Operations Research and Mathematical Economics Renmin University of China Beijin 100872 China department of Logistics The Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong

This paper gives a dynamic concept and a new non-parametric method for evaluating returns to scale（RTS） of economic units with multiple inputs and *** is frequently noticed that when we increase the input of a decision making unit（DMU） with a certain status of RTS,different status of RTS is *** example,when we increase the input of a DMU with constant RTS under the traditional method,a decreasing RTS is often observed instead of the expected constant *** thus define the RTS of each DMU in both input expansion and contraction regions *** research starts from transferring the production possibility set into the intersection form,by giving the explicit linear inequality representation of production *** RTS structural characteristics of DMUs＇ on the production frontier are *** of RTS of those DMUs on the production frontier include increasing RTS,constant RTS,decreasing RTS,saturated RTS and evidence of *** and suficient conditions for RTS evaluation are *** definition and evaluation method given here provide more detailed economic characteristics of DMU for policy makers.

关键词： DEA production possibility set returns to scale