آزمایش رسانایی الکتریکی اصلاح‌شده برای سنجش مقاومت بتن درمقابل نفوذ یون‌های کلرید

نوع مقاله : پژوهشی

نویسندگان

• امیررضا پیلوار ¹
• علی اکبر رمضانیانپور ²
• حسین رجایی ²

¹ موسسه آموزش عالی توس.

² دانشگاه صنعتی امیرکبیر

10.22067/civil.v29i2.48944

چکیده

در این مقاله روشی جدید برای سنجش مقاومت بتن در مقابل نفوذ یون‌های کلرید ارائه شده است که شامل اشباع‌سازی نمونه‌ها توسط محلول NaCl 5 مول، قبل از اندازه‌گیری رسانایی آنها می‌باشد. با اشباع کردن نمونه‌ها توسط محلول با رسانایی بالا، رسانایی‌های نمونه‌های مختلف بتنی متناسب با ساختار منافذ آنها می‌شود. برای بررسی عملکرد این روش، طرح‌های اختلاط مختلف بتن ساخته شد. مشاهده گردید که نتایج روش ارائه‌شده حساسیت کمتری نسبت به رسانایی مایع منفذی درمقایسه با روش‌های آزمایش نفوذ تسریع‌یافتۀ یون‌های کلرید (RCPT) و رسانایی حجمی (BC) دارد. همچنین ارتباط خوبی بین نتایج این روش با نتایج آزمایش انتشار حجمی (BD) به‌دست آمد.

کلیدواژه‌ها

• بتن، نفوذپذیری کلریدی
• رسانایی الکتریکی
• مایع منفذی

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عنوان مقاله [English]

Modified Electrical Conductivity Test Method for Evaluation Concrete Chloride Ion Permeability

نویسندگان [English]

• Amirreza Pilvar ¹
• Ali Akbar Ramezanianpour ²
• Hosein rajaie ²

² Amirkabir University of Technology

چکیده [English]

Standard test method for bulk electrical conductivity (ASTM C1760) provides a rapid indication of the concrete’s resistance to the penetration of chloride ions by diffusion. In this paper a new approach for assessing the bulk electrical conductivity of saturated specimens of hardened concrete is presented. The test involves saturating concrete specimens with a 5 M NaCl solution before measuring the conductivity of the samples. By saturating specimens with a highly conductive solution, they showed virtually the same pore solution conductivity. Different concrete samples yield different conductivity primarily due to differences in their pore structure. The feasibility of the method has been demonstrated by testing different concrete mixtures consisting ordinary and blended cement of silica fume (SF) and calcined perlite powder (CPP). Two standard test methods of RCPT (ASTM C1202) and Bulk Conductivity (ASTM C1760) were also applied to all of the samples. The results show that for concretes containing SF and CPP, the proposed method is less sensitive towards the variations in the pore solution conductivity in comparison with RCPT and Bulk Conductivity tests. It seems that this method is suitable for the assessment of the performance and durability of different concretes containing supplementary cementitious materials.

کلیدواژه‌ها [English]

• concrete
• Chloride Permeability
• Conductivity
• Pore Solution

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