ارائه معادلات مورد نیاز جهت اندازه گیری مقاومت فشاری سنگ ها و بتن ها، با به کارگیری آزمون نوین "پیچش" و مقایسه ی آن با آزمون های استاندارد

نوع مقاله : مقاله پژوهشی

نویسندگان

1 استاد، دانشکده فنی و مهندسی عمران، دانشگاه بین المللی امام خمینی (ره)

2 دکتری، دانشکده فنی و مهندسی عمران، دانشگاه بین المللی امام خمینی (ره)

3 کارشناس ارشد، دانشکده فنی و مهندسی عمران، دانشگاه بین المللی امام خمینی (ره)

چکیده

در کارهای مهندسی به ویژه در مهندسی ژئوتکنیک، مهندسی عمران و مهندسی معدن، قبل یا پس از ساخت سازه ها مواردی پیش می‌آید که نیاز به تعیین مقاومت برجای سنگ یا بتن، ضروری می‌باشد. در این خصوص می توان تغییر در کاربری سازه (تغییر در بار وارده)، نامطلوب بودن شرایط اجرا، کمبود زمان، عدم دسترسی به تجهیزات آزمایشگاهی و آسیب دیدگی سازه را از جمله دلایل برای ارزیابی مقاومت مصالح به صورت برجا بر شمرد. روشهای متعددی برای آزمایش مصالح وجود دارد که یا مخرب می باشند و یا دارای وسایل گران قیمت و وارداتی هستند. در این مقاله با استفاده از آزمون نوین "پیچش" اقدام به اندازه گیری مقاومت 9 نوع سنگ مختلف و بتن با هشت رده مقاومتی مختلف شده است. همچنین ضمن مقایسه نتایج با روش های استاندارد، نمودارهای کالیبراسیون و معادلات مورد نیاز جهت تبدیل نتایج آزمون "پیچش" به مقاومت فشاری مصالح مذکور ارائه گردیده است. با توجه به نتایج حاصله می توان برای اندازه گیری مقاومت فشاری بتن های معمولی با استفاده از آزمون پیچش، از رابطه y=19.27x^0.67 با ضریب تعیین حدود 95/0 استفاده نمود. همچنین برای سنگ های استفاده شده در این تحقیق نیز می توان با بکارگیری معادله y=27.87x^0.52، مقاومت فشاری سنگ های مذکور را با استفاده از آزمون پیچش با دقت بالای 94 درصد تعیین نمود.

کلیدواژه‌ها


عنوان مقاله [English]

Offer the equations required to measure the compressive strength of rocks and concretes, using the new "Twist-off" test and compare it with standard methods

نویسندگان [English]

  • Mahmood Naderi 1
  • Ali Saberi Varzaneh 2
  • Abolfazl Rashvand Aveh 3
1 Professor, Faculty of Technical and Civil Engineering, Imam Khomeini International University, Qazvin, Iran.
2 Ph.D, Faculty of Technical and Civil Engineering, Imam Khomeini International University, Qazvin, Iran.
3 Master, Faculty of Technical and Civil Engineering, Imam Khomeini International University, Qazvin, Iran.
چکیده [English]

In engineering works, especially in geological sciences, civil engineering and mining engineering, before or after the construction of structures, there are cases where it is necessary to determine the strength of stone or concrete. In this regard, changes in the use of the structure (change in load), unfavorable operating conditions, lack of time, lack of access to laboratory equipment and structural damage are among the reasons for assessing the strength of materials in situ. There are several methods for testing materials that are either destructive or have expensive and imported equipment. In this paper, using the new "Twist-off" test, the strength of 9 different types of stone and concrete with eight different strength classes has been measured. Also, while comparing the results with standard methods, calibration diagrams and equations required to convert the results of the "Twist-off" test to the compressive strength of the mentioned materials are presented. According to the results, to measure the compressive strength of ordinary concrete using twist-off test, the relationship y = 19.27x0.67 with a coefficient of determination of about 0.95 can be used. Also, for the rocks used in this research, by using the equation y = 27.87x0.52, the compressive strength of the mentioned rocks can be determined by using the twist-off test with an accuracy of 94%.

کلیدواژه‌ها [English]

  • "Twist-off" method
  • Insitu strength
  • Stone
  • Concrete
  • calibration diagram
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