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Enhancing fatigue life of cylinder-crown integrated structure by optimizing dimension
Weiwei ZHANG,Xiaosong WANG,Zhongren WANG,Shijian YUAN
《机械工程前沿(英文)》 2015年 第10卷 第1期 页码 102-110 doi: 10.1007/s11465-015-0329-y
Cylinder-crown integrated hydraulic press (CCIHP) is a new press structure. The hemispherical hydraulic cylinder also functions as a main portion of crown, which has lower weight and higher section modulus compared with the conventional hydraulic cylinder and press crown. As a result, the material strength capacity is better utilized. During the engineering design of cylinder-crown integrated structure, in order to increase the fatigue life, structural optimization on the basis of the adaptive macro genetic algorithms (AMGA) is first conducted to both reduce weight and decrease peak stress. It is shown that the magnitude of the maximum principal stress is decreased by 28.6%, and simultaneously the total weight is reduced by 4.4%. Subsequently, strain-controlled fatigue test is carried out, and the stress-strain hysteresis loops and cyclic hardening curve are obtained. Based on linear fit, the fatigue properties are calculated and used for the fatigue life prediction. It is shown that the predicted fatigue life is significantly increased from 157000 to 1070000 cycles after structural optimization. Finally, according to the optimization design, a 6300 kN CCIHP has been manufactured, and priority application has been also suggested.
关键词: cylinder-crown integrated hydraulic press (CCIHP) adaptive macro genetic algorithms (AMGA) strain-controlled fatigue test
Concepts and implementation of strain-based criteria in design codes for steel structures
Reidar BJORHOVDE
《结构与土木工程前沿(英文)》 2012年 第6卷 第3期 页码 210-216 doi: 10.1007/s11709-012-0165-7
关键词: steel stress-strain characteristics tension test strain design actual behavior improved design codes
A new method of studying collapsibility of loess
Yuanqing ZHU , Zhenghan CHEN ,
《结构与土木工程前沿(英文)》 2009年 第3卷 第3期 页码 305-311 doi: 10.1007/s11709-009-0040-3
关键词: triaxial apparatus for collapsible soils controlled suction pressure/volume controlled equipment double triaxial collapsible test single triaxial collapsible test
李仲,张航,古源,南勇,陈立宏
《中国工程科学》 2012年 第14卷 第1期 页码 86-89
DX桩是近年兴起的新型变截面桩型,其独有的承力盘很好地改善了沉降问题。通过室内小比尺模型试验,得出DX桩承载力及沉降特性的相关规律,为DX桩承载机理的研究提供进一步的试验支持。试验主要采用应变片测量桩身受力情况,桩顶设置百分表测量沉降情况,加载装置采用砝码以及杠杆分级加载。试验主要为与直孔桩对比试验以及DX桩平行试验。试验结果证明DX桩在承载力和沉降方面都优于直孔桩;上盘承载力大于下盘,随桩顶荷载增大,下盘承载所占比重有所提高。
Experimental investigation of fatigue behavior of spur gear in altered tooth-sum gearing
H. K. SACHIDANANDA, Joseph GONSALVIS, H. R. PRAKASH
《机械工程前沿(英文)》 2012年 第7卷 第3期 页码 268-278 doi: 10.1007/s11465-012-0331-6
This paper deals with the contact stress, power loss, and pitting of spur gear tooth in altered tooth-sum gearing for a tooth-sum of 100 teeth when altered by±4% tooth-sum. Analytical and experimental methods were performed to investigate and compare the altered tooth-sum gearing against the standard tooth-sum gearing. The experiments were performed using a power recirculating type test rig. The tooth loads for the experimental investigations were determined considering the surface durability of gears. A clear picture of the surface damage was obtained using a scanning electron microphotograph. The negative alteration in the tooth-sum performed better than the positive alteration in a tooth-sum operating between specified center distances.
关键词: spur gear power recirculating test rig altered tooth-sum gearing scanning electron microscopy (SEM)
Effect of loading rate on shear strength parameters of mechanically and biologically treated waste
《环境科学与工程前沿(英文)》 2022年 第16卷 第12期 doi: 10.1007/s11783-022-1595-7
● Mechanical behavior of MBT waste affected by loading rate was investigated.
关键词: Mechanically and biologically treated waste Landfill Triaxial test Loading rate Axial strain Shear strength parameter
Zhihua ZHANG,Huichen YU,Chengli DONG
《机械工程前沿(英文)》 2015年 第10卷 第4期 页码 418-423 doi: 10.1007/s11465-015-0362-x
Low cycle fatigue tests were conducted on the single crystal nickel-based superalloy, DD6, with different crystallographic orientations (i.e., [001], [011], and [111]) and strain dwell types (i.e., tensile, compressive, and balanced types) at a certain high temperature. Given the material anisotropy and mean stress, both orientation factor and stress range were introduced to the Smith, Watson, and Topper (SWT) stress model to predict the fatigue life. Experimental results indicated that the fatigue properties of DD6 depend on both crystallographic orientation and loading types. The fatigue life of the tensile, compressive, and balanced strain dwell tests are shorter than those of continuous cycling tests without strain dwell because of the important creep effect. The predicted results of the proposed modified SWT stress method agree well with the experimental data.
关键词: life prediction single crystal superalloy low cycle fatigue (LCF) crystallographic orientation strain dwell
张海良,沈旺,李刚,郭健
《中国工程科学》 2010年 第12卷 第7期 页码 8-12
以西堠门大桥国产1 770 MPa主缆索股制作技术为基础,进一步研究超长(≥4 250 m)大规格(≥169丝)高强度(1 860 MPa等级)主缆单元索股制造技术,同时对主缆索股的水平收放索技术和装置进行进一步的研究,为特大跨径悬索桥主缆单元索股的制造提供技术研究基础。
Juichen YANG,Hong CHEN,Yuan YUAN,Debanjan SARKAR,Jie ZHENG
《化学科学与工程前沿(英文)》 2014年 第8卷 第4期 页码 498-510 doi: 10.1007/s11705-014-1451-9
关键词: phase structure degradation polyurethanes controlled release drug delivery
Jun WU,Xuemei LIU
《结构与土木工程前沿(英文)》 2015年 第9卷 第3期 页码 323-340 doi: 10.1007/s11709-015-0301-2
关键词: high strength concrete (SHS) engineered cementitious composite interface blast test strain rate effect
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
谭忠盛,李健,薛斌,王秀英
《中国工程科学》 2009年 第11卷 第12期 页码 87-92
长期以来隧道衬砌水压力问题,一直是人们争论的焦点。依托宜万铁路岩溶隧道工程,对不同防排水方式(即全封堵、堵排结合及排放方式)的隧道衬砌水压力分布规律进行研究,研究方法主要采用模型试验及现场测试方法,模型试验的比例尺为1∶16,试验台架可同时施加土压和水压。通过模型试验得出水压力分布规律:全封堵条件下衬砌背后水压力不能折减,注浆圈也不能有效减小水压力;隧道内排水后衬砌背后水压力明显减小,并随着排水量的增加,水压力基本成直线下降;相同排水量时,注浆效果越好,衬砌背后水压力减小越明显;隧道采用全排导方式时,衬砌仍承受一定的水压。由模型试验得出的水压分布规律的部分结论,在现场水压力测试中得到了验证。
Hierarchical approach for fatigue cracking performance evaluation in asphalt pavements
Ibrahim ONIFADE, Yared DINEGDAE, Björn BIRGISSON
《结构与土木工程前沿(英文)》 2017年 第11卷 第3期 页码 257-269 doi: 10.1007/s11709-017-0410-1
关键词: fatigue cracking energy based crack initiation mechanistic approach pavement analysis
标题 作者 时间 类型 操作
Enhancing fatigue life of cylinder-crown integrated structure by optimizing dimension
Weiwei ZHANG,Xiaosong WANG,Zhongren WANG,Shijian YUAN
期刊论文
Concepts and implementation of strain-based criteria in design codes for steel structures
Reidar BJORHOVDE
期刊论文
Experimental investigation of fatigue behavior of spur gear in altered tooth-sum gearing
H. K. SACHIDANANDA, Joseph GONSALVIS, H. R. PRAKASH
期刊论文
Effect of loading rate on shear strength parameters of mechanically and biologically treated waste
期刊论文
LCF behavior and life prediction method of a single crystal nickel-based superalloy at high temperature
Zhihua ZHANG,Huichen YU,Chengli DONG
期刊论文
Synthesis and characterization of biocompatible polyurethanes for controlled release of hydrophobic and
Juichen YANG,Hong CHEN,Yuan YUAN,Debanjan SARKAR,Jie ZHENG
期刊论文
Performance of soft-hard-soft (SHS) cement based composite subjected to blast loading with consideration of interface properties
Jun WU,Xuemei LIU
期刊论文