مهندسی سازه و ساخت

مهندسی سازه و ساخت

بررسی تجربی و عددی خزش بتن سبکدانه تهیه شده با سنگدانه های سبک اسکوریا (سنگ پا) و پومیس(سنگ پوکه)

نوع مقاله : علمی - پژوهشی

نویسنده
دانشکده فنی دانشگاه شهید مدنی آذربایجان - تبریز
چکیده
خزش و جمع شدگی ناشی از انقباض (افت) دو ویژگی وابسته به زمان بتن می باشند. در این تحقیق، بصورت تجربی و تحلیل عددی خزش بتن سبک دانه که از سنگدانه های سبک اسکوریا (سنگ پا) و پومیس (سنگ پوکه) تهیه شده بود مورد ارزیابی قرار گرفته است. کرنش ناشی از خزش بتن سبک دانه با استفاده از استاندارد ASTM C512 برای مدت زمان یک سال اندازه‌گیری شده است. برای بررسی عددی خزش بتن نتایج حاصل از آزمایش در نرم افزار ABAQUS شبیه سازی شده و نتایج حاصل از نرم افزار با نتایج تجربی و روابط پیشنهادی آیین نامه های ACI و CEB مقایسه گردید. تجزیه و تحلیل نتایج تجربی و عددی نشان می دهد که رفتار بتن در دراز مدت تابع نوع سنگدانه، مقاومت فشاری بتن و تنش وارد بر نمونه ها می باشد. مقایسه کرنش ناشی از خزش پایه بتن سبک دانه با روابط پیشنهادی آیین نامه های ACI و CEB نشان می دهد در مدت یک سال رابطه پیشنهادی آیین نامه ACI با طرح اختلاط بتن S1 (درشت دانه اسکوریا و ریزدانه ماسه معمولی) و آیین نامه CEB با بتن P2 (درشت دانه پومیس و ریزدانه اسکوریا) مطابقت داشته و بعد از 365 روز رابطه پیشنهادی ACI نسبت به S1 حدود 14% و رابطه پیشنهادی CEB نسبت به P2 حدود 7% کرنش کمتری نشان داده اند. با مطالعه خزش یک ساله بتن سبک دانه با نرم افزار ABAQUS مشخص گردید تعریف پارامترهای وادادگی مناسب با نتایج تجربی در نرم افزار ABAQUS، کرنش خزشی دراز مدت تحلیلی بتن مطابقت خوبی با نتایج آزمایشگاهی خواهد داشت.
کلیدواژه‌ها

موضوعات


عنوان مقاله English

Experimental and numerical investigation of creep in lightweight aggregate concrete prepared from scoria and pumice aggregates

نویسنده English

ALIREZA ENTEZARI
Department of Civil Engineering, Azarbaijan Shahid Madani University, Tabriz, Iran
چکیده English

Creep and drying shrinkage are two time-dependent features of concrete. In this study, the creep in four types of lightweight aggregate concrete (LWAC) made from scoria and pumice aggregates is examined. The strain due to the creep of LWAC is measured over a course of one year based on ASTM C512 standard. For a numerical assessment of creep, experimental findings are simulated in ABAQUS and the obtained outputs are compared with empirical results and proposed equations in ACI and CEB regulations. Analysis of empirical and numerical results shows that the long-term concrete behaviour depends on aggregate type, concrete compressive strength and applied stress on the samples. The comparison of the creep-induced strain between this type of concrete and ACI and CEB regulations indicates that during one year, the relationship proposed by ACI is consistent with concrete S1 and CEB with concrete P2, and after 365 days age, the relationship proposed by ACI is about %14 less than S1 and the relationship proposed by CEB is about %7 less than P2. The one-year study of LWAC aided by ABAQUS clarifies by defining appropriate parameters with experimental results in ABAQUS, the analytical long-term creep strain of concrete will be in good agreement with the experimental results.

کلیدواژه‌ها English

Scoria
Lightweight concrete
Pumice
Lightweight aggregate
Creep
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  • تاریخ دریافت 04 دی 1402
  • تاریخ بازنگری 22 فروردین 1403
  • تاریخ پذیرش 06 شهریور 1403