پیوندهای مفید
آمار
| تعداد نشریات | 7 |
| تعداد شماره‌ها | 399 |
| تعداد مقالات | 5,389 |
| تعداد مشاهده مقاله | 5,288,035 |
| تعداد دریافت فایل اصل مقاله | 4,882,773 |
به کارگیری آزمون‌های پیچش و کشیدن از سطح جهت بررسی تاثیر الیاف پلی‌پروپیلن بر چسبندگی ملات با بتن و ارزیابی مقاومت فشاری درجای آن‌ها | ||
| نشریه مهندسی عمران امیرکبیر | ||
| دوره 54، شماره 5، مرداد 1401، صفحه 1675-1690 اصل مقاله (991.04 K) | ||
| نوع مقاله: مقاله پژوهشی | ||
| شناسه دیجیتال (DOI): 10.22060/ceej.2021.19711.7240 | ||
| نویسندگان | ||
| علی صابری ورزنه* 1؛ محمود نادری2 | ||
| 1دکتری سازه، دانشکده فنی و مهندسی، دانشگاه بین المللی امام خمینی (ره)، قزوین، ایران، | ||
| 2Department of Civil Engineering, Imam Khomeini International University, Qazvin, Iran | ||
| چکیده | ||
| در صنعت تعمیر بتن، چسبندگی بین لایه تعمیری و بستر بتنی، نقش تعیین کننده‌ای در عملکرد مرکب موفق لایه‌های تعمیری دارد. با توجه به پدیده جمع شدگی و تاثیر آن بر افت چسبندگی، در این مقاله تاثیر الیاف پلی‌پروپیلن بر چسبندگی ملات و بتن مورد بررسی قرار گرفت. برای انجام آزمایشات از آزمون نوین "پیچش" استفاده شد. در تمامی آزمایشات، نتایج حاصل از آزمون "پیچش" با نتایج آزمون استاندارد "کشیدن از سطح" مورد مقایسه قرار گرفت. برای تجزیه و تحلیل بیشتر نتایج به دست آمده، از آزمون‌های XRD (الگوی پراش اشعه ایکس) و SEM (میکروسکوپ الکترونی روبشی) استفاده شد. همچنین تاثیر الیاف بر جمع شدگی و مشخصات مکانیکی ملات‌های تعمیری و رابطه آن بر چسبندگی بین ملات و بتن بررسی گردید. در این خصوص از آزمون‌های درجای "پیچش" و "کشیدن از سطح" به صورت آزمایشگاهی استفاده شد. با بررسی ضریب همبستگی بین نتایج آزمون‌های درجا با آزمون‌های آزمایشگاهی، نمودارهای کالیبراسیون جهت تبدیل قرائت‌های به دست آمده از آزمون‌های "پیچش" و "کشیدن از سطح" به مقاومت فشاری ملات‌ها ارائه شد. نتایج حاصله بیانگر این بود که برای نمونه الیافی، مقدار بیشینه Ca(OH)2 یا هیدروکسیدکلسیم دچار کاهش شد که منتج به تولید بیشتر سیلیکات کلسیم هیدراته یا ژل C-S-H می‌شود که نتیجه آن بهبود خواص نهایی ملات و افزایش چسبندگی بود. همچنین به طور میانگین مقاومت چسبندگی برشی و کششی 90 روزه حاصل از آزمون‌های "پیچش" و "کشیدن از سطح" با افزودن الیاف به ترتیب به مقدار 49/5 و 43/1 درصد افزایش داشته است. | ||
| کلیدواژه‌ها | ||
| پیچش؛ کشیدن از سطح؛ چسبندگی؛ ملات؛ بتن | ||
| موضوعات | ||
| تکنولوژی بتن | ||
| عنوان مقاله [English] | ||
| Using "twist-off" and "pull-off" tests to investigate the effect of polypropylene fibers on the bond of mortar/concrete and to evaluate their in-situ compressive strength | ||
| نویسندگان [English] | ||
| Ali Saberi Vaezaneh1؛ Mahmood Naderi2 | ||
| 1Ph.D Department of Civil Engineering, Imam Khomeini International University, Qazvin, Iran | ||
| 2Department of Civil Engineering, Imam Khomeini International University, Qazvin, Iran | ||
| چکیده [English] | ||
| In the concrete repair industry, the adhesion between the repair layer and the concrete plays a decisive role in the successful composite performance of the repair layers. Due to the shrinkage and its effect on adhesion loss, in this paper, the effect of polypropylene fibers on the adhesion between mortar/concrete has been investigated. A new "twist-off" test has been used to perform the experiments. In all experiments, the results of the "twist-off" test were compared with the results of the "pull-off" test. X-ray diffraction patterns and scanning electron microscopy tests were used to further analyze the results. Also, the effect of fibers on shrinkage and mechanical properties of mortars and its relationship to adhesion between mortar and concrete were investigated. In this regard, the tests of "twist-off" and "pull-off" were used in the laboratory and compared with the outputs of computer modeling. Also, by examining the correlation coefficient between the results of in-situ tests and laboratory tests, calibration diagrams were presented to convert the readings obtained from the "twist-off" and "pull-off" tests into the compressive strength of mortars. The results indicate that for the fibrous sample, the peak intensity of Ca (OH)2 or calcium hydroxide is reduced, resulting in the production of more hydrated calcium silicate or C-S-H gel, which results in improved final properties of the mortar and increased adhesion. Also, on average, the shear and tensile bond strength of 90 days obtained from "twist-off" and "pull-off" tests with the addition of fibers increased by 49.5% and 43.1%, respectively. | ||
| کلیدواژه‌ها [English] | ||
| "Twist-off", "Pull-off", Adhesion, Mortar, Concrete | ||
|
سایر فایل های مرتبط با مقاله
|
||
| مراجع | ||
|
[1] A.M. Neville, Properties of concrete, 5 Edition, Harlow, United Kingdom, (2012), p.872. [2] M. Naderi, Adhesion of Different Concrete Repair Systems Exposed to Different Environments Journal of Adhesion, 84(1) (2008), 78-104. [3] L. Lifang, W. Peiming, Y. Xiaojie, Effect of Polypropylene Fiber on Dryshrinkage Ratio of Cement Mortar, Journal of Building Materials. 8(4) (2005), 373-377. [4] R.A.S. Mohamed, Effect of polypropylene fibers on the mechanical properties of normal concrete, Journal of Engineering Science, 34(4) (2006), 1049-1059. [5] D.S. Dharan, A. Lal, Study the effect of polypropylene fiber in concrete, International Research Journal of Engineering and Technology, 3(6) (2016), 616-619. [6] S. Vikrant, V. Kavita, S. Kene, N.V. Deshpande, Investigation on Compressive and Tensile Behavior of Fibrillated Polypropylene Fibers Reinforced Concrete, International Journal of Engineering Research Applied, 2(3) (2012), 1111-1115. [7] G.P. Tilly, J. Jacobs, Concrete repairs: Observations on performance in service and current practice, Watford, UK, (2007), ISBN: 978-1-86081-974-2. [8] H. Beushausen, M. Alexander, Localised strain and stress in bonded concrete overlays subjected to differential shrinkage. Materials Structure, 40 (2007), 189–199. [9] D. Wu, W. Gao, J. Feng, K. Luo, Structural behaviour evolution of composite steel-concrete curved structure with uncertain creep and shrinkage effects. Composite Building Engineering, 24 (2016), 261-272. [10] G. Martinola, H. Sadouki, F. Wittmann, Numerical model for minimizing the risk of damage in a repair system, Journal of Materials in Civil Engineering, 13 (2001), 121–129. [11] ASTM C1583, Standard test method for tensile strength of concrete surfaces and the bond strength or tensile strength of concrete repair and overlay materials by direct tension (pull-off method), West Conshohocken PA, American Society for Testing and Materials, (2004), p.5. [12] M. Naderi, Analysis of the slant shear test, Journal of Adhesion Science Technology, 23(2) (2009), 229-245. [13] M. Naderi, Friction-Transfer Test for the Assessment of in-situ Strength & Adhesion of Cementitious Materials, Construction and Building Materials, 19(6) (2005), 454-459. [14] M. Naderi, O. Ghodousian, Adhesion of Self-Compacting Overlays Applied to Different Concrete Substrates and Its Prediction by Fuzzy Logic, Journal of Adhesion, 88(10) (2012), 848-865. [15] M. Naderi, Effects of Cyclic Loading, Freeze-Thaw and Temperature Changes on Shear Bond Strengths of Different Concrete Repair Systems, Journal of Adhesion, 84(9) (2008), 743-763. [16] M. Naderi, R. Shibani, New Method for Nondestructive Evaluation of Concrete Strength, Australian Journal of Basic Applied Science, 7(2) (2013), 438-447. [17] M. Naderi, Evaluating in situ shear strength of bituminous pavments, In Proceedings of the institution of Civil Engineering, 4 (2006), 61-65. [18] M. Naderi, An alternative method for in situ determination of rock strength, Canadian Geotechnical Journal, 48 (2011), 1901-1905. [19] M. Santandrea, I.A.O. Imohamed, H. Jahangir, C. Carloni, C. Mazzotti, S. Miranda, P. Casadei, An investigation of the debonding mechanism in steel FRP-and FRCM-concrete joints, In 4th Workshop on the new boundaries of structural concrete. (2016), 289-298. [20] M. Bagheri, A. Chahkandi, H. Jahangir, Seismic Reliability Analysis of RC Frames Rehabilitated by Glass Fiber-Reinforced Polymers, International Journal of Civil Engineering, 17(11) (2019) 1785-1797. [21] H. Jahangir, M. R. Esfahani, Investigating loading rate and fibre densities influence on SRG-concrete bond behaviour, Steel and Composite Structures, 34(6) (2020) 877-889. [22] M.O. Kim, A. Bordelon, Fiber Effect on Interfacial Bond Between Concrete and Fiber-Reinforced Mortar. Transportation Research Board, 2591(1) (2016), 11–18. [23] S. Feng, H. Xiao, J. Geng, Bond strength between concrete substrate and repair mortar: Effect of fibre stiffness and substrate surface roughness, Cement and Concrete Composites, 114 (2020), 1-14. [24] M. Naderi, New Twist-Off Method for the Evaluation of In-Situ Strength of Concrete, Journal of Testing and Evaluation, 35(6) (2007), 602-608. [25] ASTM C128, Standard test method for relative density (specific gravity) and absorption of coarse aggregate. West Conshohocken PA, American Society for Testing and Materials, (2015), p.6. [26] ASTM C127, Standard test method for density, relative density (specific gravity), and absorption of fine aggregate. West Conshohocken PA, American Society for Testing and Materials, (2012), p.5. [27] BHRC Publication, The National Method for Concrete Mix Design. Building and Housing Research Center. No. S-479. 2008, p.50. [28] BHRC Publication, Iranian National Building Code, Division 5, Building Materials Products, (2017), p.286. [29] ASTM C157, Test method for length change of hardened hydraulic cement mortar and concrete. West Conshohocken PA, American Society for Testing and Materials, (2008), p.8. [30] ASTM C490. Standard practice for use of apparatus for the determination of length change of hardened cement paste, mortar, and concrete. West Conshohocken PA, American Society for Testing and Materials, (2011), p.5. [31] ASTM C109. Standard test method for compressive strength of hydraulic cement mortars (using 2-in. or [50-mm] cube specimens). American Society for Testing and Materials, (2013), p.12. [32] A. Alnkaa, H. Yaprak, S. Memis, G. Kaplan, Effect of Different Cure Conditions on the Shrinkage of Geopolymer Mortar, International Journal of Engineering Research and Development, 14(10) (2018), 51-55. [33] R. Chendes, S. Dan, L. Courard, Comparison of shear and pull-off tests for testing adhesion of different content limestone fillers mortars used as repair system, Construction sustainability, 15 (2013), 1-6. [34] J. Silfwerbrand, Shear bond strength in repaired concrete structures, Material Structuter, 36 (2003), 419-424. | ||
|
آمار تعداد مشاهده مقاله: 588 تعداد دریافت فایل اصل مقاله: 850 |
||
