Name: applicability analysis of assessment methods for morphological parameters of corroded steel bars
Uploaded: 2018-11-01T12:30:00
Description: Watch this Scientific Journal Video about Applicability Analysis of Assessment Methods for Morphological Parameters of Corroded Steel Bars at JoVE.com

深圳大学作者非常感谢国家自然科学基金 (51520105012 号和51278303号) 和广东省教育部 (重点) 项目的资助。(编号 2014kzdxm051), 他们还感谢深圳大学土木工程学院广东省海洋土木工程耐久性重点实验室提供的检测设施和设备。

1. 样品和制造工艺的测试
<ol><li>获得500毫米长、直径14毫米的普通钢筋 (q235 级), 用于测试试件的制造。</li>
	<li>用细砂纸擦亮棒材的表面, 以去除表面的磨机鳞片。</li>
	<li>使用切割机从左侧切割条形图30毫米和470毫米, 如图 1所示。</li>
	<li>使用数字电子秤测量三个条形图的重量。</li>
	<li>使用步骤2中描述的五种方法测量三个试件的直径, 并记录无腐蚀棒材试件?...

<ol>
	<li>Cavaco, E. S., Bastos, A., Santos, F. A. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+corrosion+on+the+behaviour+of+precast+concrete+floor+systems.">Effects of corrosion on the behaviour of precast concrete floor systems.</a> Construction &amp; Building Materials. 145, (2017).</li><li>Cavaco, E. S., Neves, L. A. C., Casas, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+the+robustness+to+corrosion+in+the+life+cycle+assessment+of+an+existing+reinforced+concrete+bridge.">On the robustness to corrosion in the life cycle assessment of an existing reinforced concrete bridge.</a> Structure and Infrastructure Engineering. 14 (2), 137-150 (2017).</li><li>Muthulingam, S., Rao, B. 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A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+degree+of+corrosion+on+the+properties+of+reinforcing+steel+bars.">Effect of degree of corrosion on the properties of reinforcing steel bars.</a> Construction &amp; Building Materials. 15 (8), 361-368 (2001).</li><li>Papadopoulos, M. P., Apostolopoulos, C. A., Alexopoulos, N. D., Pantelakis, S. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+salt+spray+corrosion+exposure+on+the+mechanical+performance+of+different+technical+class+reinforcing+steel+bars.">Effect of salt spray corrosion exposure on the mechanical performance of different technical class reinforcing steel bars.</a> Materials &amp; Design. 28 (8), 2318-2328 (2007).</li><li>Zhang, W., Song, X., Gu, X., Li, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tensile+and+fatigue+behavior+of+corroded+rebars.">Tensile and fatigue behavior of corroded rebars.</a> Construction &amp; Building Materials. 34 (5), 409-417 (2012).</li><li>Clark, L. A., Chan, A. H. C., Du, Y. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Residual+capacity+of+corroded+reinforcing+bars.">Residual capacity of corroded reinforcing bars.</a> Magazine of Concrete Research. 57 (3), 135-147 (2005).</li><li>Chan, A. H. C., Clark, L. A., Du, Y. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+corrosion+on+ductility+of+reinforcing+bars.">Effect of corrosion on ductility of reinforcing bars.</a> Magazine of Concrete Research. 57 (7), 407-419 (2005).</li><li>Zhu, W., Fran&#231;ois, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Corrosion+of+the+reinforcement+and+its+influence+on+the+residual+structural+performance+of+a+26-year-old+corroded+RC+beam.">Corrosion of the reinforcement and its influence on the residual structural performance of a 26-year-old corroded RC beam.</a> Construction &amp; Building Materials. 51 (2), 461-472 (2014).</li><li>Fran&#231;ois, R., Khan, I., Dang, V. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Impact+of+corrosion+on+mechanical+properties+of+steel+embedded+in+27-year-old+corroded+reinforced+concrete+beams.">Impact of corrosion on mechanical properties of steel embedded in 27-year-old corroded reinforced concrete beams.</a> Materials &amp; Structures. 46 (6), 899-910 (2013).</li><li>Torres-Acosta, A. A., Castro-Borges, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Corrosion-Induced+Cracking+of+Concrete+Elements+Exposed+to+a+Natural+Marine+Environment+for+Five+Years.">Corrosion-Induced Cracking of Concrete Elements Exposed to a Natural Marine Environment for Five Years.</a> Corrosion. 69 (11), 1122-1131 (2013).</li><li>Li, D., Wei, R., Du, Y., Guan, X., Zhou, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measurement+methods+of+geometrical+parameters+and+amount+of+corrosion+of+steel+bar.">Measurement methods of geometrical parameters and amount of corrosion of steel bar.</a> Construction &amp; Building Materials. 154, 921-927 (2017).</li><li>Kashani, M. M., Crewe, A. J., Alexander, N. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+a+3D+optical+measurement+technique+for+stochastic+corrosion+pattern+analysis+of+reinforcing+bars+subjected+to+accelerated+corrosion.">Use of a 3D optical measurement technique for stochastic corrosion pattern analysis of reinforcing bars subjected to accelerated corrosion.</a> Corrosion Science. 73 (13), 208-221 (2013).</li><li>Tang, F., Lin, Z., Chen, G., Yi, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three-dimensional+corrosion+pit+measurement+and+statistical+mechanical+degradation+analysis+of+deformed+steel+bars+subjected+to+accelerated+corrosion.">Three-dimensional corrosion pit measurement and statistical mechanical degradation analysis of deformed steel bars subjected to accelerated corrosion.</a> Construction &amp; Building Materials. 70 (2), 104-117 (2014).</li><li>Zhang, W., Zhou, B., Gu, X., Dai, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Probability+Distribution+Model+for+Cross-Sectional+Area+of+Corroded+Reinforcing+Steel+Bars.">Probability Distribution Model for Cross-Sectional Area of Corroded Reinforcing Steel Bars.</a> Journal of Materials in Civil Engineering. 26 (5), 822-832 (2013).</li><li>Wang, X. G., Zhang, W. P., Gu, X. L., Dai, H. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+residual+cross-sectional+areas+of+corroded+bars+in+reinforced+concrete+structures+using+easy-to-measure+variables.">Determination of residual cross-sectional areas of corroded bars in reinforced concrete structures using easy-to-measure variables.</a> Construction &amp; Building Materials. 38, 846-853 (2013).</li><li>Stewart, M. G., Al-Harthy, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pitting+corrosion+and+structural+reliability+of+corroding+RC+structures:+Experimental+data+and+probabilistic+analysis.">Pitting corrosion and structural reliability of corroding RC structures: Experimental data and probabilistic analysis.</a> Reliability Engineering &amp; System Safety. 93 (3), 373-382 (2008).</li><li>Darmawan, M. S., Stewart, M. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+Spatially+Variable+Pitting+Corrosion+on+Structural+Reliability+of+Prestressed+Concrete+Bridge+Girders.">Effect of Spatially Variable Pitting Corrosion on Structural Reliability of Prestressed Concrete Bridge Girders.</a> Australian Journal of Structural Engineering. 6 (2), 147-158 (2015).</li><li>Stewart, M. G., Mullard, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spatial+time-dependent+reliability+analysis+of+corrosion+damage+and+the+timing+of+first+repair+for+RC+structures.">Spatial time-dependent reliability analysis of corrosion damage and the timing of first repair for RC structures.</a> Engineering Structures. 29 (7), 1457-1464 (2007).</li><li>Kashani, M. M., Lowes, L. N., Crewe, A. J., Alexander, N. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Finite+element+investigation+of+the+influence+of+corrosion+pattern+on+inelastic+buckling+and+cyclic+response+of+corroded+reinforcing+bars.">Finite element investigation of the influence of corrosion pattern on inelastic buckling and cyclic response of corroded reinforcing bars.</a> Engineering Structures. 75, 113-125 (2014).</li><li>Apostolopoulos, C. A., Demis, S., Papadakis, V. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chloride-induced+corrosion+of+steel+reinforcement+-+Mechanical+performance+and+pit+depth+analysis.">Chloride-induced corrosion of steel reinforcement - Mechanical performance and pit depth analysis.</a> Construction and Building Materials. 38, 139-146 (2013).</li><li>Imperatore, S., Rinaldi, Z., Drago, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Degradation+relationships+for+the+mechanical+properties+of+corroded+steel+rebars.">Degradation relationships for the mechanical properties of corroded steel rebars.</a> Construction and Building Materials. , 219-230 (2017).</li><li>Kashani, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Size+effect+on+inelastic+buckling+behaviour+of+accelerated+pitted+1+corroded+bars+in+porous+media.">Size effect on inelastic buckling behaviour of accelerated pitted 1 corroded bars in porous media.</a> Journal of Materials in Civil Engineering. 29 (7), (2017).</li><li>Meda, A., Mostosi, S., Rinaldi, Z., Riva, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+evaluation+of+the+corrosion+influence+on+the+cyclic+behaviour+of+RC+columns.">Experimental evaluation of the corrosion influence on the cyclic behaviour of RC columns.</a> Engineering Structures. 76, 112-123 (2014).</li><li>Kashani, M. M., Crewe, A. J., Alexander, N. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structural+capacity+assessment+of+corroded+RC+bridge+piers.">Structural capacity assessment of corroded RC bridge piers.</a> Proceedings of the Institution of Civil Engineers - Bridge Engineering. 170 (1), 28-41 (2017).</li><li>National Standard of the People's Republic of China. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Standard for test methods of long-term performance and durability of ordinary concrete, Ministry of Housing and Urban-Rural Development of the People's Republic of China, GB/T 50082-2009. , (2009).</li></ol>

图 6a和6A显示, 未腐蚀棒材试样的测量直径在其长度上没有显著变化。沿杆长测量的直径之间的最大差异仅为 0.11 mm 左右, 最大偏差为0.7%。这表明, 使用游标卡尺可以很好地评估无腐蚀条形图的几何形状。但是, 在同一截面的不同角度测量的直径之间的差异是一致的, 而且差别很大。对于给定的棒材试样, 最大直径为 14.62 mm 和 14.62 mm, 角度为45°和 135°, 最大偏差为4%...

钢筋腐蚀是混凝土结构恶化的主要原因之一, 是混凝土碳化和氯部侵入造成的。在混凝土碳化中, 腐蚀倾向于广义;而在氯化物入侵, 它变得更加本地化1,2。不管是什么原因, 腐蚀会使腐蚀产品的径向膨胀导致混凝土盖发生腐蚀, 使钢筋与其周围混凝土之间的粘结变差, 穿透钢筋表面, 并减少钢筋的横截面面积相当3,4。
由于结构混凝土的非均匀性和使用环境的变化, 钢筋的腐蚀在其表面和长度上随机发生, 具有很大的不确定性。与混凝土碳化引起的广义均匀腐蚀相反, 氯离子入侵引起的点蚀引起了攻击的渗透。此外, 它还会导致腐蚀杆的残余部分在棒材表面和长度之间有很大的差异。因此, 棒材强度和杆延性降低。已经进行了广泛的研究, 以研究腐蚀对钢筋的机械性能的影响 5,6,7, 8,9,10 11,12,13,14,15。然而, 对钢筋形态参数和腐蚀特性的测量方法关注较少。
一些研究人员用质量损失来评估钢筋5、10、11、14 的腐蚀程度。但是, 此方法只能用于确定残段的平均值, 不能测量截面沿长度的分布。朱和佛朗哥改进了这种方法, 将一根钢筋切割成一系列短段, 并称重每个段, 以确定剩余截面沿其长度13,14的区域的变化。然而, 这种方法在切割过程中造成了钢材料的额外损失, 不能准确地接触到腐蚀钢筋的最小残余部分, 这决定了其承载能力。游标卡尺还用于测量 14,15钢筋的几何参数。然而, 腐蚀杆的残余截面是非常不规则的, 并且在被测量的和实际的截面尺寸之间总是有明显的偏差被腐蚀的酒吧。根据阿基米德原理, 克拉克等人采用排水法测量腐蚀杆沿长度的残余部分, 但在这种情况下, 在没有明显精度的情况下, 对钢筋的位移进行了人工控制, 但没有明显的精度11。通过使用电动机自动控制钢筋的位移, 更准确地测量结果, 改进了这种排水方法.最后, 在过去几年中, 随着三维扫描技术的发展, 该方法被用来测量钢筋的几何尺寸 17,18,19, 20.通过三维扫描, 可以精确地获得钢筋的直径、残余面积、质心、偏心、转动惯量和腐蚀渗透。尽管研究人员在不同的实验环境中使用了这些方法, 但在精度、适用性和适用性方面对这些方法没有进行比较和评价。
腐蚀, 特别是点蚀, 与广义腐蚀相比, 不仅改变了腐蚀钢筋的力学性能, 而且降低了混凝土结构的剩余承载力和使用寿命。为了更合理地评估钢筋的力学性能, 必须更准确地测量腐蚀钢筋的形态参数, 以确定钢筋长度腐蚀的空间变异性。这将有助于更准确地评估受腐蚀损坏的钢筋混凝土 (rc) 结构的安全性和可靠性21、22、23、24、25、26 ,27,28,29。
该协议比较了五种讨论的测量钢筋几何形状和腐蚀量的方法。一个单, 500 毫米长, 14 毫米直径, 平圆棒被用作样品, 并在实验室中受到加速腐蚀。在使用每种方法之前和之后, 仔细测量其形态和腐蚀程度, 包括质量损失、vernier 卡钳、排水测量、三维扫描和 x 射线微型计算机断层扫描 (xct)。最后, 对两者的适用性和适用性进行了评价。
需要注意的是, 嵌入混凝土中的带肋钢筋, 而不是暴露在空气中的普通钢筋, 通常用于混凝土结构, 并受到腐蚀。对于带肋的酒吧, vernier 卡钳可能不那么容易应用。由于这些钢筋在混凝土中腐蚀, 与暴露在空气中的钢筋相比, 它们的表面渗透更加不规则。然而, 该协议是为了在同一柱上对不同测量方法的分析的适用性而设计的;因此, 它采用赤裸的平条作为样品, 以消除肋和混凝土非均匀性对形态参数测量的影响。今后还可以进一步研究用其他方法测量腐蚀的肋钢筋。

<table>
	<tbody>
		<tr>
			<td>Supplies</td>
			<td></td>
			<td></td>
			<td></td>
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			<td>Plastic ruler</td>
			<td>Deli Group Co.,Ltd.</td>
			<td>No.6240</td>
			<td></td>
		</tr>
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			<td>white paint pen</td>
			<td>SINO PATH Enterprises.,Ltd.</td>
			<td>SP-110</td>
			<td></td>
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			<td>Tube with Branch</td>
			<td>Customized-made</td>
			<td></td>
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			<td>Measurement cylinder</td>
			<td>Beijing Huake Bomex Glass Co., Ltd.</td>
			<td></td>
			<td></td>
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		<tr>
			<td>500mL Beaker</td>
			<td>Beijing Huake Bomex Glass Co. , Ltd.</td>
			<td>CP-201</td>
			<td></td>
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			<td>sandpaper</td>
			<td>Shanghai Noon Decoration Material Co., Ltd.</td>
			<td>P04</td>
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			<td>white developer</td>
			<td>SHANGHAI XINMEIDA FLAW DETECTION MATERIAL CO., LTD.</td>
			<td>FA-5</td>
			<td></td>
		</tr>
		<tr>
			<td>Reagents</td>
			<td></td>
			<td></td>
			<td></td>
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			<td>epoxy resin adhesive</td>
			<td>Hunan Baxiongdi New Material Co., Ltd.</td>
			<td>DY&#183;E&#183;44</td>
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			<td>epoxy hardener</td>
			<td>Hunan Baxiongdi New Material Co., Ltd.</td>
			<td>DY&#183;EP</td>
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			<td>HCl</td>
			<td>Dongguan Dongjiang Chemical Reagent Co., Ltd.</td>
			<td>AR-2500ml</td>
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			<td>saturated lime water</td>
			<td>Xilong Chemical Co., Ltd.</td>
			<td>AR-500g</td>
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			<td>Equipment</td>
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			<td>Digital electronic scale</td>
			<td>Kaifeng Group Co., Ltd.</td>
			<td>Model JCS-0040</td>
			<td></td>
		</tr>
		<tr>
			<td>Digital vernier caliper</td>
			<td>Shanghai Measuring &#38; Cutting Tool Works Co., Ltd.</td>
			<td>Model ST-089-229-090</td>
			<td></td>
		</tr>
		<tr>
			<td>Cutting machine</td>
			<td>Robert Bosch GmbH</td>
			<td>TCO2000</td>
			<td></td>
		</tr>
		<tr>
			<td>3D reconstructed X-ray microscope</td>
			<td>XRADIA</td>
			<td>Model MICROXCT-400</td>
			<td></td>
		</tr>
		<tr>
			<td>3D scanner</td>
			<td>HOLON Three-dimensional Technology(Shenzhen) Co.,Ltd.</td>
			<td>Model HL-3DX+</td>
			<td></td>
		</tr>
		<tr>
			<td>Electromechanical Universal Testing Machine</td>
			<td>MTS SYSTEMS (China) Co., Ltd.</td>
			<td>Model C64.305</td>
			<td></td>
		</tr>
	</tbody>
</table>

applicability analysis of assessment methods for morphological parameters of corroded steel bars

腐蚀钢筋长度的不规则和不均匀残余截面极大地改变了其机械性能, 极大地主导了现有混凝土结构的安全性和性能。因此, 正确测量结构中钢筋的几何形状和腐蚀量, 以评估结构的剩余承载力和使用寿命, 是非常重要的。本文介绍并比较了五种不同的测量钢筋的几何形状和腐蚀量的方法。在本协议中, 单根500毫米长、直径14毫米的钢筋是受到加速腐蚀的试样。在质量损失测量、vernier 卡钳、排水测量、三维扫描和 x 射线微计算机断层扫描 (xct) 之前和之后, 对其形态和腐蚀量进行了仔细测量。然后对这些不同方法的适用性和适用性进行了评价。结果表明, vernier 卡钳是测量无腐蚀棒形态的最佳选择, 而三维扫描是最适合于定量测量腐蚀棒的形态的最佳选择。

图 6显示了500毫米长的无腐蚀棒材试样在使用 vernier 卡钳测量长度的每个截面的角度为0°、45°、90°和135°的直径。然后将条形切割成三个部分, 如图 1所示。
图 7显示了非腐蚀棒材试样沿长度的横截面面积, 分别使用四种和五种方法测量, 分别用于440毫米长的中?...

Watch this Scientific Journal Video about Applicability Analysis of Assessment Methods for Morphological Parameters of Corroded Steel Bars at JoVE.com

Applicability Analysis of Assessment Methods for Morphological Parameters of Corroded Steel Bars

本文采用不同的方法测量钢筋的几何形状和腐蚀量: 质量损失、卡钳、排水测量、三维扫描和 x 射线显微计算机断层扫描 (xct)。

钢筋形态参数评价方法的适用性分析

The irregular and uneven residual sections along the length of a corroded steel bar substantially change its mechanical properties and significantly ...

本视频旨在测量完整和腐蚀的钢筋的表面形态。我们将演示和评估五种不同的测量方法，包括质量损失、更薄的卡钳测量、排水测量、3D 扫描和钢筋的 XCT。3D 扫描是测量腐蚀棒表面腐蚀渗透空间变异性的最佳方法。使用 3D 扫描方法获得的腐蚀测量将使工程能够更精确、更可靠地评估我们社会中现有工程结构的安全性和使用寿命。演示该程序的将是实验室的技术人员韩惠来先生和深圳宏荣三维技术的技术人员崔胜林先生。首先，用10毫米的增量标记一个500毫米长、14毫米直径的钢筋。然后，使用零度线标线测量第一个标记的杆直径，钳口轻轻触摸杆。执行另外三次测量，每次旋转卡钳 45 度，以 45 度间隔总共进行四次测量。对条形上的每个标记重复此过程。平均每个标记的直径并计算横截面。然后，从条形图的每一端切割30毫米，获取两个30毫米长的条形标本和一个440毫米长的条形标本。在数字电子秤上称量每个试样并记录读数。以 10 毫米间隔标记 30 毫米长的条形标本，从左侧开始 5 毫米。如前所述，确定每个标记的平均直径。接下来，设置一个静液压、机电通用测试机，并在机头下放置一个玻璃排量缸。用自来水将气缸装满，以到达出口口。然后，在容器出口下方放置电子刻度。将 200 毫升烧杯放在秤上，与插座内线。之后，将杆试样垂直夹在 EUT 机器的头部。垂直向下移动 EUT 头，直到杆刚刚接触水面。在数字刻度上记录初始读数。然后，将 EUT 机器设置为以每分钟 10 毫米的速度向下移动柱线。运行机器以将条形置换到第一个 10 毫米标记。然后，在电子刻度上记录最终读数。对棒试样的每个 10 毫米段重复此过程，直到整个条形被淹没。之后让酒吧风干一小时。计算从置换的水面计算每个10毫米段的均匀横截面。用这种方式测试三个试样。接下来，用白色缺陷检测处理器喷洒每个干棒试样，让试样在空气中干燥。然后，在 3D 扫描仪的平台上放置一个涂层试样。使用标有随机小白点数组的标签校准条形试样位置。然后，沿样本的长度扫描，开发空间模型，并生成模型的形态学数据。对每个试样重复此项。接下来，将一个30毫米长的标本放在X射线微计算断层扫描系统的可旋转平台上。关闭 XCT 仪器。打开仪器软件，将试样移动到正确的位置进行扫描。填充所需的像素大小和放大系数。然后，扫描试样并生成几何参数。对其他 30 毫米长的试样重复此过程。获得非腐蚀钢筋的测量后，从两米长的多绞线中剥离 50 至 60 毫米的绝缘层。从另一端剥去较短的段。将导线的较长、外露端固定在 440 毫米长的试样一端，绝缘胶带牢固地包裹在杆端 70 毫米左右。然后，用绝缘胶带将酒吧另一端的70毫米牢固地包裹起来。接下来，将环氧树脂粘合剂与硬质剂混合在一对一的比例中。均匀地将环氧树脂涂抹在杆的每个绝缘端，以保护端部免受腐蚀。一旦环氧树脂干燥，在塑料罐中加注一个装有铜板的塑料罐，在自来水中用水性3.5%的氯化钠重量溶液。将杆试样放在油箱中。然后，将连接到杆的导线连接到直流电源的正端子。将铜板连接到电源的负极。设置电源以产生腐蚀电流密度，即整个酒吧每平方厘米 2.5 微安培。根据法拉第定律，在达到所需腐蚀水平所需的持续时间内应用电流。然后，关闭电流，断开棒试样，并将其浸泡在12%的盐酸水溶液中30分钟，以去除腐蚀产物。之后，将棒试样转移到饱和石灰水溶液中和酸残留物。然后，用自来水冲洗酒吧，让其在空气中干燥。接下来，以 10 毫米间隔标记腐蚀的表面。在数字电子刻度上水平称量腐蚀杆，并计算腐蚀杆的平均面积。使用测光卡钳确定每个 10 毫米标记的平均直径，并计算横截面。然后，使用置换排水方法计算腐蚀棒每个 10 毫米段的横截面。之后，用白色开发器喷洒试样，然后进行 3D 扫描。最后，从腐蚀的棒子上切出一个30毫米的段，然后用XCT扫描。在机智的钢筋的测量直径沿其长度没有显著变化，但观察到45度测量和135度测量之间的一致变化，表明钢筋是椭圆形的。质量损耗、卡钳测量和 3D 扫描技术产生了类似的值，变化小。440毫米长的试样的排水方法测量存在多种不确定性来源，包括杆的干燥和水的表面张力。使用 XCT 对 30 毫米样本进行分析，其生成的值与其他技术一致。总体而言，卡钳、XCT 和 3D 扫描以最小的变化生成了类似的值。因此，卡钳测量是获得非腐蚀棒的精确测量的最简单方法。腐蚀导致整个杆的大幅变化和横截面形状，无法用质量损失法捕获。虽然卡钳对形状变化更敏感，但它们不能解释试样表面的点蚀。XCT 和 3D 扫描产生了类似的值，但 XCT 受到对端端小样品需求限制。因此，3D测量在分析腐蚀钢筋的形态时受到青睐。更薄的卡钳是测量非腐蚀钢筋表面形态的最佳工具。而且，它易于操作。而且，这是相当经济的。排水方法测量可能会受到一些不确定性的影响，因此需要进一步改进测量装置。虽然 XCT 测量可以精确测量腐蚀钢筋的残余横截面面积，但它受试样长度限制。3D 扫描方法是测量腐蚀钢筋的最佳方法，因为它精确、经济、高效。它还可以生成有关腐蚀棒的其他有用信息。

Research

JoVE Journal

Engineering

Mechanical Expansion of Steel Tubing as a Solution to Leaky Wellbores

钢管机械性扩张为解决井眼漏

Wellbore cement, a procedural component of wellbore completion operations, primarily provides zonal isolation and mechanical support of the metal pipe ...

科研

工程学

Blast Quantification Using Hopkinson Pressure Bars

高炉利用定量霍普金森杆

Near-field blast load measurement presents an issue to many sensor types as they must endure very aggressive environments and be able to measure pressures ...

Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials

对于新材料的低温磁输运测量先进的实验方法

Novel electronic materials are often produced for the first time by synthesis processes that yield bulk crystals (in contrast to single crystal thin film ...

Methods for Measuring the Orientation and Rotation Rate of 3D-printed Particles in Turbulence

测量的方向和旋转速率方法3D打印在湍流颗粒

Experimental methods are presented for measuring the rotational and translational motion of anisotropic particles in turbulent fluid flows. 3D printing ...

The Evolution of Silica Nanoparticle-polyester Coatings on Surfaces Exposed to Sunlight

表面上的纳米硅聚酯涂料暴露在阳光下的演变

Corrosion of metallic surfaces is prevalent in the environment and is of great concern in many areas, including the military, transport, aviation, ...

Wicking Tests for Unidirectional Fabrics: Measurements of Capillary Parameters to Evaluate Capillary Pressure in Liquid Composite Molding Processes

吸湿排汗试验单向织物：毛细管参数的标准评价在液体复合成型工艺毛细管压力

During impregnation of a fibrous reinforcement in liquid composite molding (LCM) processes, capillary effects have to be understood in order to identify ...

Subsurface Defect Localization by Structured Heating Using Laser Projected Photothermal Thermography

使用激光投射光热法构造加热的地下缺陷定位

The presented method is used to locate subsurface defects oriented perpendicularly to the surface. To achieve this, we create destructively interfering ...

Preparation and High-temperature Anti-adhesion Behavior of a Slippery Surface on Stainless Steel

不锈钢滑面的制备及高温抗粘接性能研究

Anti-adhesion surfaces with high-temperature resistance have a wide application potential in electrosurgical instruments, engines, and pipelines. A ...

Preparation of Aligned Steel Fiber Reinforced Cementitious Composite and Its Flexural Behavior

定向钢纤维增强水泥基复合材料的制备及其弯曲性能研究

The aim of this work is to present an approach, inspired by the way in which a compass needle maintains a consistent orientation under the action of the ...

Generating Lap Joints Via Friction Stir Spot Welding on DP780 Steel

通过 DP780 钢上的摩擦搅拌点焊生成圈接头

Friction stir spot welding (FSSW), a derivative of friction stir welding (FSW), is a solid-state welding technique that was developed in 1991. An industry ...