استفاده بهینه میکروسیلیس در کاهش خوردگی آرماتور در سازه‌های بتنی دریایی (مطالعه موردی اسکله P1 بندر امام خمینی)

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشکده مهندسی عمران، دانشگاه آزاد اسلامی، واحد تهران مرکزی، تهران، ایران

2 دانشگاه آزاد اسلامی، واحد تهران مرکزی، تهران، ایران

چکیده

سازه‌های دریایی با توجه به موقعیت خاص جغرافیایی و سهم مهمی که در اقتصاد کشور دارند جزء سازه‌های زیربنایی به شمار می‌روند، که تعمیر و مرمت این سازه‌ها در برابر خوردگی به منظور افزایش دوام و عمر بهره‌برداری از موضوعات اساسی به حساب می‌آید. مهم‌ترین خسارت به سازه‌های بتنی دریایی در منطقه جزر و مد و در اثر خوردگی آرماتورها در بتن می‌باشد. این شرایط عمر مفید سازه‌های بتنی را کاهش می‌دهد. یکی از روش‌های موثر برای جلوگیری از خوردگی آرماتور و کاهش نفوذ یون‌های کلر در سازه‌های بتنی در محیط‌های دریایی، بهبود کیفیت و خواص مکانیکی بتن با استفاده از میکروسیلیس می‌باشد، اگرچه تاکنون مطالعات گوناگونی در مورد این موضوع انجام گرفته است ولی این مقاله در نظر دارد، استفاده بهینه میکروسیلیس در کاهش خوردگی آرماتور در سازه‌های بتنی دریایی را بر روی خواص بتن سخت شده در 18 ماه و طی زمان‌های مختلف بررسی نماید. در نمونه‌های آزمایشگاهی با نسبت آب به سیمان 34% و 40% و فوق روان کننده محدوده 3% تا 6% و میکروسیلیس با درصدهای 7، 10 و 13 ساخته شده و پس از قرارگیری در معرض شرایط تهاجمی، آزمایش سرعت خوردگی، اندازه‌گیری شده است. نتایج حاصله مبین آن است که، اثر مخلوط بتن حاوی 10% میکروسیلیس با نسبت آب به سیمان 34% دوام آرماتور در برابر خوردگی و عمر مفید سازه‌های دریایی را افزایش می‌دهد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Optimum Use of Microsilica in Reducing Corrosion Reinforcing Steel of Marine Concrete Structures

نویسندگان [English]

  • Abdolreza Tangtakabi 1
  • Mohammad Hassan Ramesht 2
  • Ali Golsoorat Pahlaviani 2
  • Towhid Pourrostam 2
1 Department of Civil Engineering, Islamic Azad University Central Tehran branch, Tehran, Iran
2 Department of Civil Engineering, Islamic Azad University Central Tehran branch, Tehran, Iran
چکیده [English]

Marine structures are considered as infrastructural structures due to their special geographical location and their important share in the country's economy. The most important damage to marine concrete structures in the tidal zone is due to the corrosion of reinforcements in concrete. These conditions reduce the useful life of concrete structures. One of the effective methods to prevent corrosion of reinforcement and reduce the penetration of chloride ions in concrete structures in marine environments is to improve the quality and mechanical properties of concrete using microsilica, although various studies have been conducted on this subject. However, this paper intends to investigate the optimal use of microsilica in reducing reinforcement corrosion in marine concrete structures on the properties of hardened concrete in 18 months and at different times. In the Sample laboratory, with a ratio of water to cement, 34% ,40% and superplasticizer range from 3% to 6%, and the microsilica with the percentages 7,10,13, made, and after the exposed conditions on aggressive, etc. testing corrosion rate, has been measured. The results show that. The effect of concrete mix containing 10% silica fume with a ratio of water to cement 34%, the durability of the reinforcement against corrosion and service life of marine structures increases.

کلیدواژه‌ها [English]

  • Marine structures
  • Reinforcement corrosion
  • Microsilica
  • Reinforcement steel concrete
  • Service life
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