بررسی رفتار دیوارهای بتنی مجهز به آلیاژهای حافظه شکلی مارتنزایتی

نوع مقاله : مقاله کامل پژوهشی

نویسندگان

1 دانشکده مهندسی عمران، دانشگاه تهران

2 مهندسی زلزله، دانشکده مهندسی عمران، دانشگاه تهران

چکیده

توجه به راهکارهایی که بتوان پس از بارگذاری شاهد کرنش­های پسماند کمتری در دیوارهای برشی بتنی بود همواره مورد توجه پژوهشگران مختلف بوده است. رفتار حافظه­شکلی آلیاژهای حافظه­دار شکلی این امکان را برای آن­ها به وجود می­آورد که پس از باربرداری با اعمال تنش و یا دما کرنش­های پسماند خود را حذف کنند. از این خاصیت می­توان جهت پیش فشرده کردن دیوارها استفاده نمود. هدف از این مقاله بررسی اثر استفاده از خاصیت حافظه شکلی مواد حافظه­دار شکلی در دیوارهای برشی با درصدهای مختلف کاربرد میلگرد آلیاژ حافظه­دار شکلی می­باشد. همچنین اثر استفاده از خاصیت حافظه شکلی مواد قبل از بارگذاری و اثر پیش­فشردگی بتن توسط این خاصیت مورد بررسی قرار می­گیرد. به این منظور، با استفاده از نرم­افزار اجزای محدود ABAQUS رفتار مدل­های مختلف مورد ارزیابی قرار می­گیرند. نتایج حاصل از این تحقیق بیانگر کاهش کرنش­های پسماند در صورت استفاده از میلگردهای آلیاژ حافظه شکلی مارتنزایتی می­باشد که البته پیش­کشیدگی قبل از بارگذاری بر اساس رفتار حافظه شکلی ضمن افزایش این اثر موجب افزایش مقاومت نیز می­گردد.

کلیدواژه‌ها


عنوان مقاله [English]

Utilizing Pretension SMAs with Memory Effect Characteristics in Concrete Structure

نویسندگان [English]

  • Mehdi Ghassemieh 1
  • Maryam Saberdel Sadeh 2
  • Mahnaz Mostafazadeh 1
1 School of Civil Engineering, University of Tehran
2 School of Civil Engineering, University of Tehran
چکیده [English]

Shape Memory Alloys (SMA) are smart and novel materials that exhibit variable stiffness and strength associated with their different polycrystalline phases. The Shape Memory Effect (SME) and Superelastic Effect (SE) are two distinct properties that make SMA a smart material. Shape memory effect (free recovery effect) means that a large (pseudo-) plastic deformation can be reversed by heating. If the going back is prevented by, e.g., concrete, a stress in the SMA results (constrained recovery effect) [1]. A Superelastic SMA can restore its initial shape spontaneously even from its inelastic range upon unloading.
The specific objective of this study is to investigate the effect of ordinary and pretension SMAs with memory effect behavior in concrete shear walls separately. For this purpose, we analyzed concrete shear walls with different percent of SMAs and steels under monotonic loading in ABAQUS Finite element. Two different concrete shear walls, one reinforced with ordinary SMA together with steel rebars and the other with pretension SMA with steel rebars, have been analyzed. The seismic behavior of the two concrete structure models has been compared in terms of their load against displacement.

کلیدواژه‌ها [English]

  • Shape memory alloys
  • Shape memory effect
  • Pretension
  • Concrete shear wall
[1]     Graesser, E. J., Cozzarelli, F. A., "Shape Memory Alloys as New Materials for Seismic Isolation", Journal of Engineering Mechanics, 1991, 117 (11), 2590-2608
[2]     Inaudi, J., Kelly, J., "Experiments on Tuned Mass Dampers Using Viscoelastic, Frictional and Shpe Memory Alloy Materials", First World Conference on Structural Control, 3-5 August, 1994, pp 127-136.
[3]     Sweeney, S. C., Hayes, J. R., "Shape Memory Alloy Dampers for Seismic Rehabilitation of Existing buildings", 27th Joint Meeting-Wind and Seismic Effects, May, 1995.
[4]     Clark, P. W., Aiken, I. D., Kelly, J. M., Higashino, M., Krumme, R., "Experimental and Analytical Studies of Shape Memory Alloy Dampers for Structural Control", SPIE Smart Materials Conference 1996.
[5]     Adachi, Y., Unjoh, S., "Development of Shape Memory Alloy Damper for Inteligent Bridge Systems", SPIE 1999, pp 31-42.
[6]     Tamai, H., Kitagawa, Y., "Pseudoelastic Behavior of Shape Memory Alloy Wire and its Application to Seismic Resistance Member for Building", IWCMM10, Galway, Ireland, August, 2000.
[7] Wilde, K., Gardoni, P., Fujino, Y., "Base Isolation System with Shape Memory Alloy Devices for Elevated Highway Bridges", Engineering Structures, 2000, 22 (3), 222-229.
[8]     Ohi, K., "Pseudo-dynamic Earthquake Response Tests and Cyclic Loading Tests on Steel Frames Including Pseudo-Elastic Elements", NSF-JSPS, US-Japan Seminar on Advanced Stability and Seismicity Concepts for Performance Based Design of Steel and Composite Structures, Kyoto, Japan, 2001.
[9]     Dolce, M., Cardone, D., "Mechanical Behavior of Shpaememoru Alloys for Seismic Applications-1. Martensite and Austenite Niti Bars Subjected to Torsion", International Journal of Mechanical Sciences, 2001, 43, 2631-2656.
[10]   Dolce, M., Cardone, D., "Mechanical Behavior of Shpae Memory Alloys for Seismic Applications-2. Austenite NiTi wires Subjected to Tension", International Journal of Mechanical Sciences, 2001, 43, 2657-77.
[11]   DesRoches, R., Delemont, M., "Seismic Retrofit of Simply Supported Bridges Using Shape Memory Alloys", Engineering Structures, 2002, 24, 325-332.
[12]   Ghassemieh, M., Iranmanesh, A. H., "Finite Element Analysis of Framed Strcutures Using Shape Memeory Alloy Braces Subjected to Seismic Loadings", ASME/ASCE/SES Conference on Mechanics and Materials, Baton Rouge, LA, US, 2005.
[13]   Abolmaali, A., Treadway, J., Aswath, P., Lu, F.k., McCarthy, E., "Hysteresis Behavior of t-stub Connections with Superelastic Shape Memory Fasteners", Journal of Constructional Steel Research, 2006, 62 (8), 831-838.
[14]   Motahari, S. A., Ghassemieh, M., "Multilinear on E-Dimensional Shape Memory Material Model for Use Instructural Engineering Applications", Engineering Structures, 2007, 29, 904-913.
[15]   Ghorbani-Renani, I., Velev, N., Tremblay, R., Palermo, D., Massicotte, B., Léger, P., "Modeling and Testing Influence of Scaling Effects on Inelastic Response of Shear Walls", ACI Structural Journal, 2009, 106 (3), 358-367.
[16]   Brocca, M., Brinson, L. C., Bazant, Z. P., "Three-Dimensional Constitutive Model for Shapememory Alloys Based on Microplane Model", Journal of the Mechanics and Physics of Solids, 2002, 50, 1051-1077.
[17]   Czaderski, C., Hahnebach, B., Motavalli, M., "RC Beam with Variable Stiffness and Strength", Journal of Construction and Building Materials, 2006, 20, 824-833.