پیوندهای مفید
آمار
| تعداد نشریات | 7 |
| تعداد شماره‌ها | 405 |
| تعداد مقالات | 5,425 |
| تعداد مشاهده مقاله | 5,559,774 |
| تعداد دریافت فایل اصل مقاله | 5,031,120 |
بررسی اثر شرایط محیطی مختلف بر زمان تعادل آب انداختگی و تبخیر در جمع شدگی خمیری روسازی‌های بتنی | ||
| نشریه مهندسی عمران امیرکبیر | ||
| مقاله 2، دوره 53، شماره 12، اسفند 1400، صفحه 5083-5102 اصل مقاله (2.49 M) | ||
| نوع مقاله: مقاله پژوهشی | ||
| شناسه دیجیتال (DOI): 10.22060/ceej.2020.18686.6927 | ||
| نویسندگان | ||
| حسن زیاری1؛ سید جواد وزیری کنگ علیائی2؛ حسن فضائلی* 3 | ||
| 1راه و ترابری دانشکده مهندسی عمران دانشگاه علم و صنعت ایران | ||
| 2گروه راه و ترابری، دانشکده مهندسی عمران، دانشگاه علم و صنعت ایران، تهران، ایران | ||
| 3دانشکده مهندسی عمران،دانشگاه آزاد اسلامی، واحد تهران، شمال، تهران، ایران | ||
| چکیده | ||
| یکی از عوامل ایجاد ترک‌های زود هنگام در روسازی‌های بتنی، جمع شدگی خمیری می‌باشد. این جمع شدگی پس از تعادل نرخ آب انداختگی و تبخیر و تشکیل فشارهای مویینگی منفی در سطح روسازی اتفاق می‌افتد. شرایط محیطی مختلف باعث تغییر در نرخ تبخیر شده و در نتیجه زمان تعادل و به دنبال آن شدت ترک خوردگی را نیز دست خوش تغییر می‌کند. در این تحقیق، با استفاده از روش استاندارد ASTM C 1579، به بررسی ارتباط بین زمان تعادل آب انداختگی و تبخیر و مساحت ترک خوردگی در بتن در 27 شرایط محیطی مختلف، شامل ترکیبی از سه دمای محیط، سه سرعت جریان باد و سه رطوبت نسبی هوا، با استفاده از سیستم تصویربرداری پیوسته و تحلیل تصاویر دیجیتال پرداخته می‌شود. نتایج تحلیل آماری داده‌ها نشان داد که بین زمان تعادل و مساحت خوردگی، ارتباط معناداری وجود دارد. با کاهش زمان تعادل به مقدار 69 دقیقه، مساحت ترک خوردگی به بیش از 4 برابر افزایش یافت. دیده شده که ترکیب هر سه عامل محیطی تاثیر بیشتری نسبت به بحرانی بودن تنها یک عامل، بر شدت ترک خوردگی دارد. همچنین رطوبت نسبی هوا بیشترین اثر را بر زمان تعادل و شدت ترک خوردگی داشته، و اثر دمای محیطی و سرعت جریان باد نزدیک به هم می‌باشد. با توجه به نتایج، بیان شد که زمان تعادل می‌تواند به عنوان معیاری مناسب جهت بررسی اثر شرایط محیطی مختلف بر شدت ترک خوردگی خمیری در روسازی‌های بتنی، مورد استفاده قرار گیرد. | ||
| کلیدواژه‌ها | ||
| جمع شدگی خمیری؛ روسازی بتنی؛ زمان تعادل؛ شدت ترک خوردگی؛ شرایط محیطی مختلف | ||
| موضوعات | ||
| انواع خرابی روسازی صلب؛ تکنولوژی بتن؛ دوام بتن | ||
| عنوان مقاله [English] | ||
| Investigation of Effects of Different Environmental Conditions on Balance Time of Bleeding and Evaporation in Plastic Shrinkage of Concrete Pavements | ||
| نویسندگان [English] | ||
| hassan ziari1؛ Seyed Javad Vaziri Kang Oleyaei2؛ Hassan Fazaeli3 | ||
| 1school of civil engineering.IUST | ||
| 2Transportation, school of civil engineering, Iran University Of science and Technology, Tehran,Iran | ||
| 3School of civil engineering, Islamic Azad University,Tehran North Branch, Tehran, Iran | ||
| چکیده [English] | ||
| One of the causes of early-age cracking in concrete pavements is plastic shrinkage. This shrinkage occurs after the balance of bleeding and evaporation and the formation of negative capillary pressures at the pavement surface. Different environmental conditions cause the rate of evaporation to change, resulting in a change in time of balance and subsequent cracking. This study, using the standard ASTM C 1579 method, examined the relationship between time of balance of bleeding and evaporation and cracking area in concrete in 27 different environmental conditions, including a combination of three ambient temperatures, three wind speeds, and three relative humidities with using a continuous video recording system and digital image analysis. The results showed that there is a significant relationship between time of balance and cracking area. By reducing the time of balance to 69 minutes, the cracking area increased more than four times. It has been shown that the combination of all three environmental factors has a more significant effect on the severity of cracking than the criticality of only one factor. Relative humidity also has the most excellent effect on the time of balance and cracking area, and the effect of ambient temperature and wind speed is close to each other. According to the results, it was stated that the time of balance might be used as a good factor to investigate the effect of different environmental conditions on the severity of plastic shrinkage cracking in concrete pavements. | ||
| کلیدواژه‌ها [English] | ||
| Plastic shrinkage, Concrete pavement, Time of balance, Severity of cracking, Different environmental conditions | ||
| مراجع | ||
|
[1] Design, Construction and Maintenance Manual for Highways Concrete Pavements No.731 in, The Ministry of Road & Urban Development. Deputy of Technical, Infrastructure and Production Affairs 2017. [2] N.J. Delatte, Concrete pavement design, construction, and performance, Crc Press, 2014. [3] Y.H. Huang, Pavement analysis and design, 2004. [4] R. Combrinck, M. Kayondo, B. le Roux, W. de Villiers, W. Boshoff, Effect of various liquid admixtures on cracking of plastic concrete, Construction and Building Materials, 202 (2019) 139-153. [5] S. Ghourchian, M. Wyrzykowski, M. Plamondon, P. Lura, On the mechanism of plastic shrinkage cracking in fresh cementitious materials, Cement and Concrete Research, 115 (2019) 251-263. [6] F. Pelisser, A.B.d.S.S. Neto, H.L. La Rovere, R.C. de Andrade Pinto, Effect of the addition of synthetic fibers to concrete thin slabs on plastic shrinkage cracking, Construction and Building Materials, 24(11) (2010) 2171-2176. [7] J. Mora-Ruacho, R. Gettu, A. Aguado, Influence of shrinkage-reducing admixtures on the reduction of plastic shrinkage cracking in concrete, Cement and Concrete Research, 39(3) (2009) 141-146. [8] A. Sivakumar, M. Santhanam, A quantitative study on the plastic shrinkage cracking in high strength hybrid fibre reinforced concrete, Cement and Concrete Composites, 29(7) (2007) 575-581. [9] P. Lura, B. Pease, G.B. Mazzotta, F. Rajabipour, J. Weiss, Influence of shrinkage-reducing admixtures on development of plastic shrinkage cracks, ACI materials journal, 104(2) (2007) 187. [10] S. Ghourchian, M. Wyrzykowski, P. Lura, A poromechanics model for plastic shrinkage of fresh cementitious materials, Cement and Concrete Research, 109 (2018) 120-132. [11] S. Ghourchian, M. Wyrzykowski, L. Baquerizo, P. Lura, Performance of passive methods in plastic shrinkage cracking mitigation, Cement and Concrete Composites, 91 (2018) 148-155. [12] G.S. Islam, S.D. Gupta, Evaluating plastic shrinkage and permeability of polypropylene fiber reinforced concrete, International Journal of Sustainable Built Environment 5(2) (2016) 345-354. [13] V. Slowik, T. Hübner, M. Schmidt, B. Villmann, Simulation of capillary shrinkage cracking in cement-like materials, Cement and Concrete Composites, 31(7) (2009) 461-469. [14] I. Bertelsen, L. Ottosen, G. Fischer, Influence of fibre characteristics on plastic shrinkage cracking in cement-based materials: A review, Construction and Building Materials, 230 (2020) 116769. [15] P.-m. Zhan, Z.-h. He, Application of shrinkage reducing admixture in concrete: A review, Construction and Building Materials, 201 (2019) 676-690. [16] W. Dias, Influence of mix and environment on plastic shrinkage cracking, Magazine of Concrete Research, 55(4) (2003) 385-394. [17] A. Almusallam, M. Maslehuddin, M. Abdul-Waris, M. Khan, Effect of mix proportions on plastic shrinkage cracking of concrete in hot environments, Construction and Building Materials, 12(6-7) (1998) 353-358. [18] S. Ghourchian, M. Wyrzykowski, L. Baquerizo, P. Lura, Susceptibility of Portland cement and blended cement concretes to plastic shrinkage cracking, Cement and Concrete Composites, 85 (2018) 44-55. [19] K. Yang, M. Zhong, B. Magee, C. Yang, C. Wang, X. Zhu, Z. Zhang, Investigation of effects of Portland cement fineness and alkali content on concrete plastic shrinkage cracking, Construction and Building Materials, 144 (2017) 279-290. [20] F. Matalkah, Y. Jaradat, P. Soroushian, Plastic shrinkage cracking and bleeding of concrete prepared with alkali activated cement, Heliyon, 5(4) (2019) e01514.https://doi.org/01510.01016/j.heliyon.02019.e01514. [21] R. Combrinck, L. Steyl, W.P. Boshoff, Interaction between settlement and shrinkage cracking in plastic concrete, Construction and Building Materials, 185 (2018) 1-11. [22] R. Combrinck, L. Steyl, W.P. Boshoff, Influence of concrete depth and surface finishing on the cracking of plastic concrete, Construction and Building Materials, 175 (2018) 621-628. [23] R. Combrinck, W.P. Boshoff, Tensile properties of plastic concrete and the influence of temperature and cyclic loading, Cement and Concrete Composites, 97 (2019) 300-311. [24] P. Zhao, A.M. Zsaki, M.R. Nokken, Using digital image correlation to evaluate plastic shrinkage cracking in cement-based materials, Construction and Building Materials, 182 (2018) 108-117. [25] M. Nasir, O.S.B. Al-Amoudi, M. Maslehuddin, Effect of placement temperature and curing method on plastic shrinkage of plain and pozzolanic cement concretes under hot weather, Construction and Building Materials, 152 (2017) 943-953. [26] H.-G. Kwak, S.-J. Ha, Plastic shrinkage cracking in concrete slabs. Part I: a numerical model, Magazine of Concrete Research, 58(8) (2006) 505-516. [27] P. Turcry, A. Loukili, Evaluation of Plastic shrinkage Cracking of self compacting concrete, (2006). [28] H.-G. Kwak, S.-J. Ha, Plastic shrinkage cracking in concrete slabs. Part II: numerical experiment and prediction of occurrence, Magazine of Concrete Research, 58(8) (2006) 517-532. [29] S. Senthilkumar, S. Natesan, Prediction of restrained plastic shrinkage cracking in plain cement concrete, Magazine of Concrete Research, 57(9) (2005) 579-587. [30] I. Yakoubi, S. Aggoun, H. Ait Aider, H. Houari, The influence of bleeding, extra water and superplasticizer on the SCC plastic shrinkage cracking: case of hot weather, Journal of adhesion science and Technology, 30(23) (2016) 2596-2618. [31] D. Meyer, W.P. Boshoff, R. Combrinck, Utilising super absorbent polymers as alternative method to test plastic shrinkage cracks in concrete, Construction and Building Materials, 248 (2020) 118666. | ||
|
آمار تعداد مشاهده مقاله: 863 تعداد دریافت فایل اصل مقاله: 1,148 |
||