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Probabilistic Models for Estimation of Random and Pseudo-Random Test Length
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作者 向东 魏道政 陈世松 《Journal of Computer Science & Technology》 SCIE EI CSCD 1992年第2期164-174,共11页
A new probabilistic testability measure is presented to ease test length analyses of random testing and pseudorandom testing.The testability measure given in this paper is oriented to signal conflict of reconvergent f... A new probabilistic testability measure is presented to ease test length analyses of random testing and pseudorandom testing.The testability measure given in this paper is oriented to signal conflict of reconvergent fanouts.Test length analyses in this paper are based on a hard fault set,calculations of which are practicable and simple.Experimental results have been obtained to show the accuracy of this test length analyser in comparison with that of Savir,Chin and McCluskey,and Wunderlich by using a pseudorandom test generator combined with exhaustive fault simulation. 展开更多
关键词 test Probabilistic Models for Estimation of Random and Pseudo-Random test length length test
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A method for determining the small-sample test length of carrier rocket 被引量:1
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作者 段晓君 王正明 《Science China(Technological Sciences)》 SCIE EI CAS 2002年第6期620-631,共12页
To satisfy the demand of test evaluation of carrier rocket, the character of aerocraft and the primary flight error should be well considered. By making full use of tracking data and ground test data, a new method is ... To satisfy the demand of test evaluation of carrier rocket, the character of aerocraft and the primary flight error should be well considered. By making full use of tracking data and ground test data, a new method is provided to expand sample size through converting the system error of guidance instruments (SEGI) of special case into standard case. In terms of the prior distribution of the SEGI coefficients, a novel model, named Bayes spline model, is developed for precision evaluation, and its performance is analyzed subsequently. For a given threshold of precision,the test length can be determined by the posterior variance with the afore-mentioned model. Finally, it is proved by theoretical analysis and simulation that this method has clear engineering background and is able to fully exploit the test resources and enables us to draw a more reasonable conclusion. 展开更多
关键词 SMALL sample BAYES SPLINE model test length.
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ON RELATION BETWEEN SIZE DEVIATION OF RAW SILK AND TESTING-LENGTH
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作者 白伦 《苏州大学学报(工科版)》 CAS 1996年第S3期23-33,共11页
Based on the auto- corrclation coefficient model.we gave an expression ofsize deviation of raw silk when testing- length is equal to a fraction for the unitlength,and discussed how the ratio of the size deviatinons by... Based on the auto- corrclation coefficient model.we gave an expression ofsize deviation of raw silk when testing- length is equal to a fraction for the unitlength,and discussed how the ratio of the size deviatinons by different testing-length fluctuates with the pseudo- cycle.Using these results as a basis,weexamined how the size deviation with the continuous property of raw silk sizechanges when changing the testing- length from 450 m to ll2.5m.Then weexamined the problem of quality control of raw silk. 展开更多
关键词 testing-length. SIZE deviation. Auto-correlation coefficient.Continuos property of RAW SILK SIZE
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Testing of Cotton Fiber Length
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作者 Liu Ruohua(刘若华) +1 位作者 Li Ruqin(李汝勤) 《Journal of Donghua University(English Edition)》 EI CAS 2001年第1期116-119,共4页
To understand the influences of actual sampling conditions on cotton fiber length testing, this article presents a theoretic study on the distributions and fibrogram of the sample taken out by sampler from ideal slive... To understand the influences of actual sampling conditions on cotton fiber length testing, this article presents a theoretic study on the distributions and fibrogram of the sample taken out by sampler from ideal sliver at a certain angle. From the distributions expression it can be found that the size of the sampler and the sampling angle are important factors which affect sampling, but if the sampling width is narrow enough, the influence of the sampling angle on the distributions and fibrogram is small enough to be omitted. This is an important conclusion for sampling, in light of this, some suggestions for designing new type sampler are put forward. 展开更多
关键词 COTTON fiber length testing IDEAL sliver hock-grip type sampling method SAMPLE distribution fibrogram.
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钢筋螺旋肋灌浆套筒连接性能试验分析
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作者 魏嘉奇 李明越 姜洪斌 《哈尔滨工业大学学报》 EI CAS 北大核心 2025年第1期110-119,共10页
传统灌浆套筒制造过程繁琐、原材料成本高且灌浆质量难以保证,限制了中国预制装配式建筑的推广。为促进建筑行业的经济、环保和高效发展,本课题组研发了一种新型钢筋灌浆套筒连接技术,采用了“滚压螺旋肋灌浆套筒”和“类宾汉流体灌浆料... 传统灌浆套筒制造过程繁琐、原材料成本高且灌浆质量难以保证,限制了中国预制装配式建筑的推广。为促进建筑行业的经济、环保和高效发展,本课题组研发了一种新型钢筋灌浆套筒连接技术,采用了“滚压螺旋肋灌浆套筒”和“类宾汉流体灌浆料”,钢筋与灌浆料、灌浆料与套筒之间形成了更加紧密的机械锁合,显著提高了构件连接后的承载力。该技术具有成本低廉、施工简便、灌浆质量易于保证等优点。为了探究该连接体系下钢筋的最小锚固长度及钢筋对中对接与偏置对接在连接性能上的差异,通过对34个接头试件进行单向拉伸试验,分析了试件的破坏模式及各项结构性能指标。研究结果表明:钢筋在套筒内部偏置对接与对中对接在连接性能上差别不大;滚压套筒内的内凸肋显著增强了对灌浆料滑移的阻抗作用,可提供足够的黏结锚固以达到连接性能要求。初步结果显示,在该连接方式下钢筋的最小锚固长度可采用10倍钢筋直径,并采用偏置对接方式。 展开更多
关键词 螺旋肋灌浆套筒 钢筋偏置对接 单拉试验 锚固长度 黏结强度
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大深宽比矩形高层建筑表面脉动风压非高斯特性
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作者 袁家辉 陈水福 刘奕 《哈尔滨工业大学学报》 EI CAS 北大核心 2025年第1期46-55,共10页
为探究大深宽比矩形高层建筑表面脉动风压的非高斯特性,本文对深宽比为1/9~9的矩形高层建筑进行了同步测压风洞试验。基于试验结果,分析了建筑表面风压的三阶和四阶统计矩分布特性,对高层建筑各立面风压进行高斯与非高斯分布的分区;研... 为探究大深宽比矩形高层建筑表面脉动风压的非高斯特性,本文对深宽比为1/9~9的矩形高层建筑进行了同步测压风洞试验。基于试验结果,分析了建筑表面风压的三阶和四阶统计矩分布特性,对高层建筑各立面风压进行高斯与非高斯分布的分区;研究了风压的空间相关系数与非高斯性强度的关系,提出了一种新的估算建筑侧风面平均再附长度的计算方法。结果表明:在建筑侧风面上,脉动风压服从高斯还是非高斯分布取决于测点到迎风前缘的距离;除了以往文献指出的迎风面角部、侧风面分离区和背风面风压呈现非高斯性外,再附区后面的风压也呈现出高度的非高斯性;本文提出的相关系数法在计算平均再附长度时具有良好的准确性,利用该方法获得了矩形高层建筑侧风面的平均再附长度沿高度的变化呈抛物线形状。 展开更多
关键词 矩形高层建筑 非高斯特性 风洞试验 相关系数 平均再附长度
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CORE-UNIFIED SOC TEST DATA COMPRESSION AND APPLICATION
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作者 Yi Maoxiang Guo Xueying +2 位作者 Liang Huaguo Wang Wei Zhang Lei 《Journal of Electronics(China)》 2010年第1期79-87,共9页
The pattern run-length coding test data compression approach is extended by introducing don't care bit(x) propagation strategy into it.More than one core test sets for testing core-based System-on-Chip(SoC) are un... The pattern run-length coding test data compression approach is extended by introducing don't care bit(x) propagation strategy into it.More than one core test sets for testing core-based System-on-Chip(SoC) are unified into a single one,which is compressed by the extended coding technique.A reconfigurable scan test application mechanism is presented,in which test data for multiple cores are scanned and captured jointly to make SoC test application more efficient with low hardware overhead added.The proposed union test technique is applied to an academic SoC embedded by six large ISCAS'89 benchmarks,and to an ITC' 02 benchmark circuit.Experiment results show that compared with the existing schemes in which a core test set is compressed and applied independently of other cores,the proposed scheme can not only improve test data compression/decompression,but also reduce the redundant shift and capture cycles during scan testing,decreasing SoC test application time effectively. 展开更多
关键词 System-on-Chip(SoC) test application time Pattern run-length X-propagation Union test RECONFIGURATION
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Influence of Slot Defect Length on Magnetic Flux Leakage
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作者 Songling HUANG, Luming LI, Haiqing YANG and Keren SHIDepartment of Electrical Engineering, Tsinghua University, Beijing 100084, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第2期231-232,共2页
A key issue, which influences the applications of magnetic flux leakage testing, is defect quantification. There have been many research on the relationship between width, depth and magnetic flux leakage of slot defec... A key issue, which influences the applications of magnetic flux leakage testing, is defect quantification. There have been many research on the relationship between width, depth and magnetic flux leakage of slot defect. However, the length factor is often ignored. The relationship between characteristics of defect leakage field and defect length was investigated. The magnetic flux leakages of a series of plate specimens with the same width, same depth and different length slot defects were tested under the same magnetizing conditions. Testing results show that defect length is an important parameter needed to consider in quantifying defects. 展开更多
关键词 Magnetic flux leakage (MFL) testing Defect quantification Slot length
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导弹整机贮存寿命加速试验建模与评估技术
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作者 张生鹏 唐宇彬 +2 位作者 张安琪 马小兵 李宏民 《航天器环境工程》 CSCD 2024年第6期742-750,共9页
针对多失效模式、多失效机理、小子样导弹整机产品贮存寿命加速试验与评估面临的难题,提出整机贮存寿命加速试验建模方法,通过建立基于竞争失效的整机贮存寿命模型,综合考虑零部组件产品的贮存寿命信息,开展整机加速因子综合计算;提出... 针对多失效模式、多失效机理、小子样导弹整机产品贮存寿命加速试验与评估面临的难题,提出整机贮存寿命加速试验建模方法,通过建立基于竞争失效的整机贮存寿命模型,综合考虑零部组件产品的贮存寿命信息,开展整机加速因子综合计算;提出基于试验长度因子的小子样整机贮存可靠度评估方法,通过加长试验时间达到利用小子样验证高贮存可靠度的目的。最后给出典型伺服机构加速试验案例分析,证明方法的有效性。该方法可为开展小子样整机产品贮存寿命加速试验与寿命评估提供一种新的技术途径。 展开更多
关键词 小子样导弹整机产品 贮存寿命 加速试验建模 试验长度因子 可靠度评估
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Laboratory pull-out tests on fully grouted rock bolts and cable bolts:Results and lessons learned 被引量:19
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作者 Isabelle Thenevin Laura Blanco-Martín +3 位作者 Faouzi Hadj-Hassen Jacques Schleifer Zbigniew Lubosik Aleksander Wrana 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第5期843-855,共13页
Laboratory pull-out tests were conducted on the following rock bolts and cable bolts:steel rebars,smooth steel bars,fiberglass reinforced polymer threaded bolts,flexible cable bolts,IR5/IN special cable bolts and Mini... Laboratory pull-out tests were conducted on the following rock bolts and cable bolts:steel rebars,smooth steel bars,fiberglass reinforced polymer threaded bolts,flexible cable bolts,IR5/IN special cable bolts and Mini-cage cable bolts.The diameter of the tested bolts was between 16 mm and 26 mm.The bolts were grouted in a sandstone sample using resin or cement grouts.The tests were conducted under either constant radial stiffness or constant confining pressure boundary conditions applied on the outer surface of the rock sample.In most tests,the rate of displacement was about 0.02 mm/s.The tests were performed using a pull-out bench that allows testing a wide range of parameters.This paper provides an extensive database of laboratory pull-out test results and confirms the influence of the confining pressure and the embedment length on the pull-out response(rock bolts and cable bolts).It also highlights the sensitivity of the results to the operating conditions and to the behavior of the sample as a whole,which cannot be neglected when the test results are used to assess the bolt-grout or the grouterock interface. 展开更多
关键词 Pull-out test Fully grouted bolts Laboratory-scale Confining pressure Embedment length Bolt-grout interface
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常导高速磁浮工程试验线初期建设长度研究
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作者 牟瀚林 徐绪宝 +2 位作者 马卫华 吴杰 禹壮壮 《铁道工程学报》 EI CSCD 北大核心 2024年第8期52-56,共5页
研究目的:我国常导高速磁浮已具备推进工程化试验和示范运营线建设的条件,需要建设工程试验线对高速磁浮关键技术进行验证。本文从常导高速磁浮工程试验线初期试验需求入手,工程试验线建设初期不考虑乘坐舒适性,尽量采用较大的加减速度... 研究目的:我国常导高速磁浮已具备推进工程化试验和示范运营线建设的条件,需要建设工程试验线对高速磁浮关键技术进行验证。本文从常导高速磁浮工程试验线初期试验需求入手,工程试验线建设初期不考虑乘坐舒适性,尽量采用较大的加减速度,在满足初期达速试验需求的前提下减少初期试验线建设长度,节省试验线初期工程投资。研究结论:(1)高速磁浮工程试验线主要是确认时速600 km时的各种性能及实用化目标的有关试验;(2)工程试验线初期建设长度需满足列车加减速运行最小距离及一定匀速运行距离要求,在国产时速600 km常导高速磁浮列车参数一定的情况下,加减速度主要取决于牵引变流器的额定电压及最大电流,通过供电系统匹配性仿真计算,车辆越轻,定子分段长度越短,可提供的车辆加速度越大,工程试验线初期建设长度越短;(3)本研究结论可为常导高速磁浮工程试验线的建设提供参考。 展开更多
关键词 高速磁浮 工程试验线 初期建设长度
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A Novel Variable Shifting Code for Test Compression of SoC
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作者 Xiao-Le Cui Liang Yin Jin-Xi Hong Ren-Fu Zuo Xiao-Xin Cui Wei Cheng 《Journal of Electronic Science and Technology of China》 2009年第4期375-379,共5页
The test vector compression is a key technique to reduce IC test time and cost since the explosion of the test data of system on chip (SoC) in recent years. To reduce the bandwidth requirement between the automatic ... The test vector compression is a key technique to reduce IC test time and cost since the explosion of the test data of system on chip (SoC) in recent years. To reduce the bandwidth requirement between the automatic test equipment (ATE) and the CUT (circuit under test) effectively, a novel VSPTIDR (variable shifting prefix-tail identifier reverse) code for test stimulus data compression is designed. The encoding scheme is defined and analyzed in detail, and the decoder is presented and discussed. While the probability of 0 bits in the test set is greater than 0.92, the compression ratio from VSPTIDR code is better than the frequency-directed run-length (FDR) code, which can be proved by theoretical analysis and experiments. And the on-chip area overhead of VSPTIDR decoder is about 15.75 % less than the FDR decoder. 展开更多
关键词 FDR code run-length code test data compression VSPTIDR code.
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Methodology for Evaluating and Monitoring of Waterworks Performance Efficiency—Part 2: Test of Filterability
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作者 Frantisek Hereit Pavel Polasek 《Advances in Chemical Engineering and Science》 2014年第4期470-482,共13页
The effectiveness of deep-bed filtration with respect to suspension formed during the preceding processes is evaluated by the test of filterability. The properties and concentration of the suspension being filtered ar... The effectiveness of deep-bed filtration with respect to suspension formed during the preceding processes is evaluated by the test of filterability. The properties and concentration of the suspension being filtered are affected by the efficiency of the preceding aggregation and separation processes. The basic principles of the test of filterability are based on the mechanistic model of filtration. The equations in the mathematical model of the mechanistic conception of filtration are derived from the theory of filtration. The arrangement of the pilot filtration plant for the determination of filterability of flocculent suspension is presented in this paper. The test of filterability is carried out with a thin-layer filter element. The design of a filter element arrangement and its installation are also disclosed in this paper. The inter-dependence of the coefficient of filtration efficiency on the specific volume of intercepted suspensions, filter media grain sizes and different filtration velocities are graphically presented. In addition, the effect of the filter bed clogging resulting from the properties of different suspensions on the head loss generated, the length of filtration cycle and quality of filtrate produced are also shown in this paper. 展开更多
关键词 Deep-Bed FILTRATION MECHANISTIC Model of FILTRATION test of FILTERABILITY FILTRATION Element length of FILTRATION Cycle
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600 MPa级钢筋套筒灌浆连接性能试验研究
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作者 郑永峰 孙富爽 +2 位作者 解鸣 刘秀斌 丁鑫 《建筑技术》 2024年第16期1933-1937,共5页
为研究600 MPa级钢筋套筒灌浆连接性能,设计制作了24个钢筋连接接头试件,并进行单向拉伸试验。研究结果表明:增大钢筋锚固长度、增加套筒环肋数量、提高灌浆料强度,均可提高接头的极限荷载,减小残余变形。当钢筋锚固长度为8 d、套筒环... 为研究600 MPa级钢筋套筒灌浆连接性能,设计制作了24个钢筋连接接头试件,并进行单向拉伸试验。研究结果表明:增大钢筋锚固长度、增加套筒环肋数量、提高灌浆料强度,均可提高接头的极限荷载,减小残余变形。当钢筋锚固长度为8 d、套筒环肋数量不少于4道时,进一步增加了套筒环肋数量,对接头抗拉强度的影响较小,但仍可较明显地减小接头残余变形。对于22 mm的600 MPa级钢筋套筒灌浆连接,建议钢筋锚固长度不小于8 d,套筒每端环肋数量不少于5道,灌浆料抗压强度宜不小于80 MPa。 展开更多
关键词 600 MPa级钢筋 灌浆套筒 单向拉伸试验 锚固长度 残余变形
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空间引力波星载望远镜测试与评估技术研究进展 被引量:1
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作者 张兰强 曾意 +5 位作者 吴小虎 杨金生 阮晓莉 辛强 顾乃庭 饶长辉 《光电工程》 CAS CSCD 北大核心 2024年第2期6-21,共16页
在空间引力波探测任务中,星载望远镜承担太空超长干涉光路双向光束准直的重要作用。空间引力波探测对星载望远镜提出了pm级光程稳定性和低于10^(-10)级后向杂散光水平的极高要求。超高水平指标要求超过了当前测试技术的精度极限,因此,... 在空间引力波探测任务中,星载望远镜承担太空超长干涉光路双向光束准直的重要作用。空间引力波探测对星载望远镜提出了pm级光程稳定性和低于10^(-10)级后向杂散光水平的极高要求。超高水平指标要求超过了当前测试技术的精度极限,因此,针对星载望远镜发展测试与评估技术并开展系统超高精度测试是空间引力波探测计划成功的重要前提。本文在概述国内外在研的空间引力波探测星载望远镜研制情况的基础上,重点围绕星载望远镜的核心技术指标——光程稳定性和后向杂散光,介绍了在研望远镜的测试技术发展现状和已经取得的部分测试成果,以及各研究单位进一步的测试计划,为我国的空间引力波探测的星载望远镜测试与评估技术发展提供参考。 展开更多
关键词 空间引力波探测 星载望远镜 地面测试 光程稳定性 后向杂散光
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地铁列车概念车性能模拟及特殊工况仿真计算软件在试车线长度计算中的应用 被引量:1
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作者 陈世浩 张彦栋 《科技创新与应用》 2024年第7期193-196,共4页
中铁二院开发的地铁列车概念车性能模拟及特殊工况仿真计算软件,可根据地铁车辆基本参数、牵引及制动特性,建立地铁列车概念车牵引计算模型,对地铁列车概念车其余特性曲线进行计算,验证拟选用的车辆能否匹配当前线路及运营要求。试车线... 中铁二院开发的地铁列车概念车性能模拟及特殊工况仿真计算软件,可根据地铁车辆基本参数、牵引及制动特性,建立地铁列车概念车牵引计算模型,对地铁列车概念车其余特性曲线进行计算,验证拟选用的车辆能否匹配当前线路及运营要求。试车线是地铁列车进行动态调试和试验的线路,试车线设计应尽可能满足车辆最高运行速度的试车需求。该文利用该软件,计算80 km/h时速及100 km/h时速地铁列车空载AW0工况在不同档位试车速度下试车线长度,并给出试车线长度建议方案。 展开更多
关键词 地铁车辆 牵引特性 试车速度 试车线 长度计算
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Flexural Bond Behavior of Rebar in Ultra-High Performance Concrete Beams Considering Lap-Splice Length and Cover Depth
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作者 Seongjun Kim Jungwoo Lee +1 位作者 Changbin Joh Imjong Kwahk 《Engineering(科研)》 2016年第3期116-129,共14页
This study intends to find out the correlation between the cover depth and the bond characteristics of UHPC through pull-out tests of UHPC specimens with different cover depths and bond tests of rebar using flexural m... This study intends to find out the correlation between the cover depth and the bond characteristics of UHPC through pull-out tests of UHPC specimens with different cover depths and bond tests of rebar using flexural members. In this experimental study, specimens are fabricated with the lap-splice length as test variable in relation with the calculation of the lap-splice length for 180- MPa UHPC. Moreover, specimens are also fabricated with the cover depth as test variable to evaluate the effect of the cover depth on the UHPC flexural members. The load-displacement curves are analyzed for each of these test variables to compute the lap-splice length proposed in the K-UHPC structural design guideline and to evaluate the influence of the cover depth on the flexural members. As a result, the stability of the structural behavior can be significantly enhanced by increasing slightly the cover depth specification of the current UHPC Structure Design Guideline from the maximum value between 1.5 times of rebar diameter and 20 mm to the maximum value between 1.5 times of rebar diameter and 25 mm. 展开更多
关键词 Bond Behavior Ultra High Performance Concrete (UHPC) Lap-Splice length Cover Depth Flexural Bond test Full-Out test
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玉米秸秆切碎还田机参数仿真优化与试验 被引量:1
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作者 宋金库 李辉 +5 位作者 张华 刘小龙 孙伟 陈扬洲 王帅 袁永威 《林业机械与木工设备》 2024年第2期37-42,共6页
针对现有的玉米秸秆切碎还田机秸秆粉碎长度过长,在后续免耕播种中导致播种开沟器易堵塞的问题。采用正交试验设计方法,结合多体动力学软件RecurDyn和田间试验,以秸秆粉碎长度为试验指标,机具的行驶速度、偏心圆盘的转速、切碎刀杆的长... 针对现有的玉米秸秆切碎还田机秸秆粉碎长度过长,在后续免耕播种中导致播种开沟器易堵塞的问题。采用正交试验设计方法,结合多体动力学软件RecurDyn和田间试验,以秸秆粉碎长度为试验指标,机具的行驶速度、偏心圆盘的转速、切碎刀杆的长度为试验因素,选用L_(27)(3^(13))正交表,通过虚拟仿真试验方法,仿真得出每种方案的试验结果。对试验结果通过极差分析和方差分析,得出秸秆切碎还田机最优参数组合:圆盘转速700 r/min、机具行驶速度3 km/h、刀杆长度为200 mm。田间重复试验表明,最优参数组合条件下秸秆粉碎长度达到49.2 mm,比虚拟仿真试验得出的秸秆粉碎长度(47.7 mm)长1.5 mm,田间试验结果与仿真试验结果吻合度高,可以为同类型的玉米秸秆切碎还田机的设计提供参考。 展开更多
关键词 秸秆还田机 切碎长度 RecurDyn仿真 正交试验 轨迹
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圆截面组合桩加固滑坡的作用机理与合理嵌固深度物理模型试验研究
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作者 宋成彬 李长冬 +3 位作者 王贵华 姚文敏 贺鑫 方堃 《安全与环境工程》 CAS CSCD 北大核心 2024年第1期135-149,共15页
目前在滑坡治理中,大截面人工挖孔桩因存在施工安全隐患大和效率低下等问题已在部分行业领域被限制使用,开展可机械化施工的圆截面组合桩研究已成为新的趋势,但当前对圆截面组合桩变形受力机理与合理嵌固深度的研究尚不够深入。基于自... 目前在滑坡治理中,大截面人工挖孔桩因存在施工安全隐患大和效率低下等问题已在部分行业领域被限制使用,开展可机械化施工的圆截面组合桩研究已成为新的趋势,但当前对圆截面组合桩变形受力机理与合理嵌固深度的研究尚不够深入。基于自主研发的圆截面组合桩加固滑坡物理模型试验系统,开展了不同工况下圆截面组合桩加固滑坡的物理模型试验,分析了滑体的变形演化过程,研究了圆截面组合桩加固下滑体与抗滑桩的变形受力特征,并对比分析了不同嵌固深度和桩顶连系梁对圆截面组合桩变形特征的影响,揭示了圆截面组合桩加固滑坡的作用机理。结果表明:①滑体的变形演化过程可分为压密、匀速变形、加速变形和变形破坏4个阶段;②前后桩均存在反弯点,反弯点会随着试验进程向桩顶移动,且后桩的反弯点更接近于滑动面;③当一排桩的嵌固深度保持不变、另一排桩的嵌固深度改变时,可将36%的桩长作为合理的嵌固深度;④连系梁使后桩的最大桩顶位移减小了15.6%,而对前桩的影响不大;⑤连系梁的存在降低了滑动面处的最大桩身弯矩,从而使得桩身弯矩分布更加合理。该研究成果有望为圆截面组合桩的设计提供借鉴和参考。 展开更多
关键词 滑坡加固 圆截面组合桩 加固机理 嵌固深度 物理模型试验
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钢纤维掺量对变形钢筋与超高性能混凝土黏结性能影响 被引量:2
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作者 胡翱翔 邱敏 《广东土木与建筑》 2024年第1期96-101,共6页
为研究钢纤维掺量对变形钢筋与超高性能混凝土(UHPC)黏结性能的影响,设计、制作了6组18个中心拔出试件,钢纤维体积掺量为0%~5%,室外养护28 d后进行中心拔出试验,观察试件的破坏形态、黏结应力-滑移曲线、最大黏结强度及其对应的滑移等... 为研究钢纤维掺量对变形钢筋与超高性能混凝土(UHPC)黏结性能的影响,设计、制作了6组18个中心拔出试件,钢纤维体积掺量为0%~5%,室外养护28 d后进行中心拔出试验,观察试件的破坏形态、黏结应力-滑移曲线、最大黏结强度及其对应的滑移等。试验结果表明:随着纤维掺量的增加试件的破坏形态从脆性破坏转变为韧性破坏;纤维掺量对黏结强度影响不大,各组黏结强度均处于60 MPa左右,峰值滑移随着纤维掺量增加而增大;纤维掺量为3%时黏结强度最大,黏结应力-滑移曲线下降段最平缓,韧性最大。建立了黏结强度与抗压强度之间的关系;建议直径16 mm的HRB500型钢筋,在UHPC中最小锚固长度试验值取2.5d;最后给出了黏结应力-滑移曲线上升段计算模型。试验结果可为UHPC材料的工程应用提供参考。 展开更多
关键词 超高性能混凝土 钢纤维掺量 黏结性能 中心拔出试验 锚固长度 分析模型
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