مهندسی سازه و ساخت

مهندسی سازه و ساخت

بررسی رابطه بین مقاومت الکتریکی حجمی و سطحی بتن حاوی میکروسیلیس

نوع مقاله : علمی - پژوهشی

نویسندگان
1 گروه مهندسی عمران، دانشکده مهندسی و فناوری، دانشگاه مازندران ، بابلسر، ایران
2 گروه مهندسی عمران، دانشکده مهندسی و فناوری، دانشگاه مازندران، بابلسر، ایران
3 گروه مهندسی برق، دانشکده مهندسی و فناوری، دانشگاه مازندران، بابلسر، ایران
چکیده
این مقاله تأثیر میکروسیلیس به‌عنوان جایگزین جزئی سیمان بر مقاومت فشاری، مقاومت الکتریکی و دوام بتن را بررسی کرده است. نمونه‌ها با درصدهای مختلف میکروسیلیس (0 تا 30 درصد وزنی سیمان) و نسبت ثابت آب به سیمان (48/0) ساخته شدند و تحت آزمایش‌های مختلف مکانیکی و الکتریکی قرار گرفتند. نتایج نشان دادند که افزودن میکروسیلیس تا 15 درصد موجب افزایش قابل‌توجه مقاومت فشاری (بیشینه مقدار64/588 کیلوگرم بر سانتی‌متر مربع در سن 120 روز) و بهبود ساختار ماتریس بتن می‌شود. با افزایش درصد میکروسیلیس به بیش از 15 درصد، کاهش مقاومت فشاری به دلیل کاهش میزان سیمان هیدراته‌شده و افزایش مواد غیرواکنشی مشاهده شد. همچنین، مقاومت الکتریکی حجمی و سطحی بتن با افزایش میکروسیلیس تا 20 درصد به‌طور چشمگیری افزایش یافت، که نشان‌دهنده کاهش نفوذپذیری و افزایش مقاومت در برابر عوامل خورنده است. میکروسیلیس با تبدیل هیدروکسید کلسیم به ژل سیلیکات کلسیم هیدراته (CSH)، باعث کاهش تخلخل، بهبود چگالی ماتریس بتن و افزایش دوام بتن در برابر نفوذ یون‌های کلرید و سایر عوامل شیمیایی مخرب شد. این مطالعه رابطه خطی و معناداری بین مقاومت الکتریکی حجمی و سطحی بتن) 99/0 (R²> را نشان داد و استفاده از مقاومت الکتریکی را به‌عنوان یک روش سریع و غیرمخرب برای ارزیابی کیفیت بتن پیشنهاد کرد. یافته‌ها کاربرد بالقوه بتن‌های حاوی میکروسیلیس در سازه‌های تحت شرایط محیطی سخت، نظیر مناطق ساحلی و صنعتی، را تأیید می‌کند.
کلیدواژه‌ها

موضوعات


عنوان مقاله English

Investigating the Relationship Between Bulk and Surface Electrical Resistivity in Concrete Containing Microsilica

نویسندگان English

Ahmad Salehi 1
Ehsan Jahani 2
Mohammad Rezanejad 3
1 Department of Civil Engineering, Faculty of Engineering and Technology, Mazandaran University, Babolsar, Iran
2 Civil Engineering Department, Technology and Engineering Faculty, Mazandaran University, Babolsar, Iran
3 Electrical Engineering Department, Technology and Engineering Faculty, Mazandaran University, Babolsar, Iran
چکیده English

This paper investigates the effects of microsilica as a partial replacement for cement on the compressive strength, electrical resistance, and durability of concrete. Concrete specimens were prepared with varying percentages of microsilica (0 to 30% by cement weight) and a constant water-to-cement ratio (0.48). The specimens were tested for various mechanical and electrical properties. The results indicated that adding up to 15% microsilica significantly increased compressive strength (maximum value of 588.64 kg/cm² at 120 days) and improved the matrix structure of the concrete. However, microsilica content beyond 15% resulted in reduced compressive strength due to decreased hydrated cement content and increased non-reactive materials. Additionally, bulk and surface electrical resistivity increased significantly up to 20% microsilica replacement, indicating reduced permeability and enhanced resistance to corrosive agents. Microsilica transforms calcium hydroxide into calcium silicate hydrate (CSH) gel, reducing porosity, improving the matrix density, and increasing the durability of concrete against the penetration of chloride ions and other harmful chemical agents. A linear and significant correlation (R² > 0.99) was observed between bulk and surface electrical resistivity. These findings suggest that electrical resistivity can be used as a quick and non-destructive method for assessing concrete quality, particularly for microsilica-containing concretes in harsh environmental conditions such as coastal and industrial areas.

کلیدواژه‌ها English

Concrete Durability
Cement
Microsilica
Permeability
Electrical Resistivity
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  • تاریخ دریافت 13 فروردین 1404
  • تاریخ بازنگری 22 خرداد 1404
  • تاریخ پذیرش 25 تیر 1404