Search | Engineering

订阅投稿

首页工程期刊工程焦点工程成就工程前沿关于我们 English

资源类型

期刊论文 166

会议视频 4

年份

2024 1

2023 15

2022 16

2021 12

2020 7

2019 13

2018 7

2017 8

2016 3

2015 2

2014 8

2013 6

2012 13

2011 8

2010 2

2009 10

2008 10

2007 5

2006 5

2005 2

展开︾

关键词

裂缝 6

微地震监测 4

2023全球十大工程成就 2

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

12相整流 1

CBC－MAC模式 1

CCM模式 1

CO2管道；离岸CCUS；海底管道；管道腐蚀；管道断裂；泄漏监测 1

CTR模式 1

Cuk矩阵变换器 1

EBSD 1

Maradbcm算法 1

PMAC模式 1

S-57 1

展开︾

检索范围：

排序：展示方式：

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

HTML PDF 收藏

砼非标准三点弯曲梁试件双K断裂参数

吴智敏,徐世烺,丁一宁,卢喜经,刘佳毅,丁生根

《中国工程科学》 2001年第3卷第4期页码 76-81

摘要：

采用跨高比为2.5的非标准三点弯曲梁试件，利用在试验中测得的最大荷载P_max及对应的裂缝口张开位移CMOD_c，根据渐近线性叠加假设，求得了砼裂缝亚临界扩展量∆a_c。在此基础上，采用虚拟裂缝模型计算了不同初始缝长、不同试件髙度的砼非标准三点弯曲梁试件的起裂断裂韧度Kⁱⁿⁱ_IC、失稳断裂韧度K^un_IC及临界裂缝尖端张开位移CTOD_c。计算结果表明，砼K^un_IC：与试件高度及初始缝高比无关；而Kⁱⁿⁱ_IC在初始缝髙比a₀/h = 0.3〜0.5内，也是一稳定的常数且与试件高度无关。这说明砼双K断裂参数可以作为砼的材料常数。

关键词：砼三点弯曲梁断裂参数

HTML PDF 收藏

黏聚裂纹阻抗的弯曲梁承载力

王利民,徐世,任传波

《中国工程科学》 2007年第9卷第2期页码 30-35

摘要：

在混凝土类软化材料断裂研究中，裂纹端部损伤区被简化为具有黏聚应力分布的非线性裂纹，该黏聚力对裂纹扩展有阻抗作用。裂纹体的应力强度因子是断裂力学标志载荷作用与几何构型因素的量化表达指标；黏聚力形成的阻抗强度因子数值，与黏聚裂纹长度和材料极值拉伸应力存在数量关系。通过双K断裂判据，以带切口的三点弯曲梁为断裂力学模型，分析了裂纹黏聚阻力对断裂过程的影响规律，计算该弯曲梁结构断裂试样的最大承担载荷；其结果比较符合实验数据。

关键词：黏聚裂纹三点弯曲梁混凝土双K断裂参数结构承载力

HTML PDF 收藏

Tests on impact effect of partial fracture at steel frame connections

CHEN Yiyi, BIAN Ruoning

《结构与土木工程前沿（英文）》 2008年第2卷第4期页码 295-301 doi: 10.1007/s11709-008-0049-z

摘要： Impact effect of sudden fracture at steel frame connections under severe earthquake or other extreme loads is presented in this paper. The relation of impulse caused by structural fracture to the release of inner force at the cracked location, the magnitude of the response to impact on the basis of one degree of freedom model, and the ratio of the peak value of response to natural period of the system are investigated. Two types of fracture tests were designed and carried out both on uniaxial steel bar tensioned and moment resistant steel frame model. It is proven that the response during the fracture process can be measured quite well using high-frequency data processing system. It is also revealed that the instant fracture of structural connection is characterized by progressive and partial fracture. Numerical evaluation of the impact effect of connection fracture is carried out.

关键词： structural fracture natural fracture progressive high-frequency

HTML PDF 收藏

Effect of fly ash replacement level on the fracture behavior of concrete

Mahdi AREZOUMANDI, Jeffery S. VOLZ

《结构与土木工程前沿（英文）》 2013年第7卷第4期页码 411-418 doi: 10.1007/s11709-013-0228-4

摘要： The production of portland cement–the key ingredient in concrete–generates a significant amount of carbon dioxide. However, due to its incredible versatility, availability, and relatively low cost, concrete is the most consumed manmade material on the planet. One method of reducing concrete’s contribution to greenhouse gas emissions is the use of fly ash to replace a significant amount of the cement. ?This study presents the results of an experimental investigation that evaluates effect of fly ash replacement level on the fracture energy of concrete. This study includes four mixes with 0%, 30%, 50%, and 70% fly ash as a cement replacement. This experimental program consisted of 32 fracture beams to study the fracture behavior of concrete. The experimental fracture energies were compared with the fracture energy provisions of different design codes and also different analytical equations. Furthermore, statistical data analyses (parametric and non-parametric) were performed to evaluate whether or not there is any statistically significant difference between the experimental fracture energies of different mixes. Results of these statistical tests show that the mix with higher level of fly ash replacement level has higher fracture energy.

关键词： concrete fracture energy fly ash

HTML PDF 收藏

Computational modeling of fracture in concrete: A review

Luthﬁ Muhammad Mauludin, Chahmi Oucif

《结构与土木工程前沿（英文）》 2020年第14卷第3期页码 586-598 doi: 10.1007/s11709-020-0573-z

摘要： This paper presents a review of fracture modeling of concrete. The complex material, such as concrete, has been widely used in construction industries and become trending issue in the last decades. Based on comprehensive literature review, there are two main approaches considered to-date of concrete fracture modeling, such as macroscopic and micromechanical models. The purpose of this review is to provide insight comparison from different techniques in modeling of fracture in concrete which are available. In the first section, an overview of fracture modeling in general is highlighted. Two different approaches both of macroscopic and micromechanical models will be reviewed. As heterogeneity of concrete material is major concern in micromechanical-based concrete modeling, one section will discuss this approach. Finally, the summary from all of reviewed techniques will be pointed out before the future perspective is given.

关键词： concrete fracture macroscopic micromechanical heterogeneity

HTML PDF 收藏

Computational modeling of fracture in capsule-based self-healing concrete: A 3D study

《结构与土木工程前沿（英文）》 2021年第15卷第6期页码 1337-1346 doi: 10.1007/s11709-021-0781-1

摘要： We present a three-dimensional (3D) numerical model to investigate complex fracture behavior using cohesive elements. An efficient packing algorithm is employed to create the mesoscale model of heterogeneous capsule-based self-healing concrete. Spherical aggregates are used and directly generated from specified size distributions with different volume fractions. Spherical capsules are also used and created based on a particular diameter, and wall thickness. Bilinear traction-separation laws of cohesive elements along the boundaries of the mortar matrix, aggregates, capsules, and their interfaces are pre-inserted to simulate crack initiation and propagation. These pre-inserted cohesive elements are also applied into the initial meshes of solid elements to account for fracture in the mortar matrix. Different realizations are carried out and statistically analyzed. The proposed model provides an effective tool for predicting the complex fracture response of capsule-based self-healing concrete at the meso-scale.

关键词： 3D fracture self-healing concrete spherical cohesive elements heterogeneous

HTML PDF 收藏

Evaluating the material strength from fracture angle under uniaxial loading

Jitang FAN

《结构与土木工程前沿（英文）》 2019年第13卷第2期页码 288-293 doi: 10.1007/s11709-018-0480-8

摘要： The most common experimental methods of measuring material strength are the uniaxial compressive and tensile tests. Generally, shearing fracture model occurs in both the tests. Compressive strength is higher than tensile strength for a material. Shearing fracture angle is smaller than 45° under uniaxial compression and greater than 45° under uniaxial tension. In this work, a unified relation of material strength under uniaxial compression and tension is developed by correlating the shearing fracture angle in theory. This constitutive relation is quantitatively illustrated by a function for analyzing the material strength from shear fracture angle. A computational simulation is conducted to validate this theoretical function. It is full of interest to give a scientific illustration for designing the high-strength materials and engineering structures.

关键词： strength fracture mechanics

HTML PDF 收藏

A dimensional analysis on asphalt binder fracture and fatigue cracking

Qian ZHAO, Zhoujing YE

《结构与土木工程前沿（英文）》 2018年第12卷第2期页码 201-206 doi: 10.1007/s11709-017-0402-1

摘要： Fracture and fatigue cracking in asphalt binder are two of most serious problems for pavement engineers. In this paper, we present a new comprehensive approach, which consists both of dimensional analysis using Buckingham Theorem and -integral analysis based on classic fracture mechanics, to evaluate the fracture and fatigue on asphalt binder. It is discovered that the dimensional analysis could provide a new perspective to analyze the asphalt fracture and fatigue cracking mechanism.

关键词： Dimensional analysis asphalt fracture fatigue cracking

HTML PDF 收藏

Experimental research on ductile fracture criterion in metal forming

Song YU, Weiming FENG

《机械工程前沿（英文）》 2011年第6卷第3期页码 308-311 doi: 10.1007/s11465-011-0233-z

摘要：

Ductile fracture criterion is key limitation parameter in material forming. Accuracy predicting surface and internal failure in plastic deformation process affects on the technology design of workpiece and die greatly. Tension, compression, torsion and shearing test on 45# steel are utilized for providing the experimental values of the critical values at fracture, and 11 widely used ductile fracture criterion are selected to simulate the physical experiments and their relative accuracy for predicting and quantifying fracture initiation sites are investigated. The comparing results show that metal forming process under high triaxiality can be estimated successively using both Normalized Cockcroft-latham and the Brozzo ductile fracture criteria, but the Ayada and general Rice-Tracey model work very well for the low triaxiality cases.

关键词： ductile fracture criteria metal forming process material experiment stress triaxiality

HTML PDF 收藏

Hybrid deep learning model for risk prediction of fracture in patients with diabetes and osteoporosis

《医学前沿（英文）》 2022年第16卷第3期页码 496-506 doi: 10.1007/s11684-021-0828-7

摘要： The fracture risk of patients with diabetes is higher than those of patients without diabetes due to hyperglycemia, usage of diabetes drugs, changes in insulin levels, and excretion, and this risk begins as early as adolescence. Many factors including demographic data (such as age, height, weight, and gender), medical history (such as smoking, drinking, and menopause), and examination (such as bone mineral density, blood routine, and urine routine) may be related to bone metabolism in patients with diabetes. However, most of the existing methods are qualitative assessments and do not consider the interactions of the physiological factors of humans. In addition, the fracture risk of patients with diabetes and osteoporosis has not been further studied previously. In this paper, a hybrid model combining XGBoost with deep neural network is used to predict the fracture risk of patients with diabetes and osteoporosis, and investigate the effect of patients’ physiological factors on fracture risk. A total of 147 raw input features are considered in our model. The presented model is compared with several benchmarks based on various metrics to prove its effectiveness. Moreover, the top 18 influencing factors of fracture risks of patients with diabetes are determined.

关键词： XGBoost deep neural network healthcare risk prediction

HTML PDF 收藏

A concise review about fracture assessments of brittle solids with V-notches

Hsien-Yang YEH, Bin YANG

《结构与土木工程前沿（英文）》 2019年第13卷第2期页码 478-485 doi: 10.1007/s11709-019-0520-z

摘要：

A concise review of recent studies about the fracture assessments of elastic brittle solid materials containing V-notches is presented. In this preliminary and brief survey, elastic stress distributions in V-notched solids are discussed first. The concept of notch stress intensity factor is introduced. Combine the digital image correlation method with numerical computation techniques to analyze the stress distribution near the notches. Fracture criteria such as strain energy density, J-integral, theory of critical distance are used.

关键词： fracture assessment brittle solids V-notches review

HTML PDF 收藏

Measurement of dynamic fracture toughness and failure behavior for explosive mock materials

Pengwan CHEN, Zhongbin ZHOU, Shaopeng MA, Qinwei MA, Fenglei HUANG

《机械工程前沿（英文）》 2011年第6卷第3期页码 292-295 doi: 10.1007/s11465-011-0237-8

摘要：

In this work, a pre-cracked semi-circular shaped explosive simulant was loaded using a split Hopkinson pressure bar (SHPB). A high-speed camera was used to capture the deformation and fracture process of the specimen in situ. The digital images were processed using the digital image correlation (DIC) method. Next, full displacement and strain fields were obtained. The displacement vector field shows that the specimen fractured under tensile stress action. The strain field can be used to predict the crack propagation. Results show that the method of combined DIC and SHPB is effective to study the dynamic deformation and fracture behavior of explosive simulants. In addition, the specimen was loaded using a drop weight. The fracture toughness of the specimen was preliminary measured.

关键词： digital image correlation polymer bonded explosive simulant split Hopkinson pressure bar (SHPB) semicircular bending test deformation fracture toughness

HTML PDF 收藏

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

HTML PDF 收藏

A continuous/discontinuous deformation analysis (CDDA) method based on deformable blocks for fracture

Yongchang CAI, Hehua ZHU, Xiaoying ZHUANG

《结构与土木工程前沿（英文）》 2013年第7卷第4期页码 369-378 doi: 10.1007/s11709-013-0222-x

摘要： In the framework of finite element meshes, a novel continuous/discontinuous deformation analysis (CDDA) method is proposed in this paper for modeling of crack problems. In the present CDDA, simple polynomial interpolations are defined at the deformable block elements, and a link element is employed to connect the adjacent block elements. The CDDA is particularly suitable for modeling the fracture propagation because the switch from continuous deformation analysis to discontinuous deformation analysis is natural and convenient without additional procedures. The SIFs (stress intensity factors) for various types of cracks, such as kinked cracks or curved cracks, can be easily computed in the CDDA by using the virtual crack extension technique (VCET). Both the formulation and implementation of the VCET in CDDA are simple and straightforward. Numerical examples indicate that the present CDDA can obtain high accuracy in SIF results with simple polynomial interpolations and insensitive to mesh sizes, and can automatically simulate the crack propagation without degrading accuracy.

关键词： fracture crack propagation deformable block continuous/discontinuous deformation analysis (CDDA)