| تعداد نشریات | 284 |
| تعداد نشریات سازمان | 82 |
| تعداد شماره‌ها | 3,079 |
| تعداد مقالات | 34,340 |
| تعداد مشاهده مقاله | 47,569,097 |
| تعداد دریافت فایل اصل مقاله | 78,584,319 |
مقایسۀ نتایج آزمون درجای "محفظۀ استوانه‌ای" و استاندارد بریتانیا و مطالعۀ موردی نفوذپذیری کانال آبرسانی | ||
| تحقیقات مهندسی سازه های آبیاری و زهکشی | ||
| دوره 26، تابستان - شماره پیاپی 99، تیر 1404، صفحه 110-95 اصل مقاله (1.32 M) | ||
| نوع مقاله: مقاله پژوهشی | ||
| شناسه دیجیتال (DOI): 10.22092/idser.2025.369716.1623 | ||
| نویسندگان | ||
| علی صابری ورزنه* 1؛ محمود نادری2 | ||
| 1پژوهشگر پسادکترا، گروه عمران، دانشکده فنی و مهندسی، دانشگاه بین المللی امام خمینی (ره)، قزوین، ایران. | ||
| 2پروفسور، گروه عمران، دانشکده دانشکده فنی و مهندسی، دانشگاه بین المللی امام خمینی (ره)، قزوین، ایران. | ||
| چکیده | ||
| این پژوهش با هدف ارزیابی نفوذپذیری یک کانال آبرسانی و شناسایی میزان تلفات آب ناشی از ناکارایی بتن بدنه بهاجرا در آمده است. آزمون "محفظۀ استوانه‌ای" نیزبه‌صورت درجا و غیرمخرب پیشنهاد و اجرا شده است. در مجموع ۵۴ نمونۀ بتنی شامل ۲۷ نمونه عمل‌آوری‌شده در آب و ۲۷ نمونه عمل‌آوری‌شده در شرایط محیطی، تحت آزمون "محفظۀ استوانه‌ای" با فشار ثابت ۵ بار به مدت ۵ ساعت قرار گرفتند. برای صحت‌سنجی نتایج، آزمون استاندارد BS EN 12390‑8 نیز روی همان نمونه‌ها و تحلیل رگرسیونی دو روش اجرا شد. نتایج تحقیق نشان داد ضریب همبستگی بین دو روش برابر 0/98 است که نشان از دقت مناسب نتایج آزمون درجا. برای کاربردهای میدانی، اندازه‌گیری مستقیم عمق نفوذ امکان‌پذیر نیست، زیرا اندازه‌گیری مستقیم ذاتاً روشی است مخرب و نیازمند مغزه‌گیری از عضو سازه‌ای است. به‌منظور رفع این محدودیت، از یکی از مزایای کلیدی روش محفظه استوانه‌ای استفاده شد: قابلیت اندازه‌گیری حجم کل آب نفوذ کرده به سطح بتن در بازه زمانی مشخص تحت هد هیدرولیکی ثابت. تحلیل آماری اختلاف نتایج با استفاده از شاخص‌های میانگین درصد خطا و ضریب همبستگی خطی نشان داد که اختلاف میانگین حجم نفوذ بین آنچه از این مطالعه به دست آمده است و داده‌های مرجع کمتر از 10در صد است و ضریب همبستگی معادل 0/97 به‌دست آمد. این نتایج اختلاف کم و همبستگی بالای داده‌ها را تأیید می کند و بیانگر دقت و اعتبار روش آزمون محفظۀ استوانه‌ای در تعیین رده‌بندی نفوذپذیری بتن است. اندازه‌گیری درجا روی 11 نقطه منتخب از کانال آب شهر ورزنه نشان داد که نفوذپذیری در تمام نقاط بیش از ۲۵ میلی‌لیتر است و در محدوده نفوذپذیری بالا قرار دارد. این مقادیر بیانگر هدررفت قابل‌توجه آب است. با آزمون جیوه و عکسبرداری SEM مشاهده شد که عمل‌آوری نشدن باعث افزایش تخلخل و حجم کلی منافذ موجود در بتن به ترتیب برابر 7 و 69/4 درصد است. | ||
| کلیدواژه‌ها | ||
| نفوذپذیری؛ کاهش دبی؛ بتن؛ آزمون درجا | ||
| عنوان مقاله [English] | ||
| Comparison of In‑situ ‘Cylindrical Chamber’ Test Results with British Standard Method and Case Study on the Permeability of the Water Supply Canal | ||
| نویسندگان [English] | ||
| Ali Saberi Varzaneh1؛ Mahmood Naderi2 | ||
| 1Postdoc researcher, Civil Engineering Faculty, Imam Khomeini International University, Qazvin, Iran. | ||
| 2Professor, Civil Engineering Faculty, Imam Khomeini International University, Qazvin, Iran. | ||
| چکیده [English] | ||
| Extended Abstract Introduction This study aimed to evaluate the permeability of a water supply canal and to quantify water losses arising from the inefficiency of the concrete lining. The “cylindrical chamber” test was proposed and implemented as an in-situ, non-destructive method. A total of 54 concrete specimens—27 water-cured and 27 cured under ambient conditions—were tested using the cylindrical chamber method under a constant pressure of 5 bar for 5 hours. To validate the results, the BS EN 12390 8 standard test was also performed on the same specimens, and regression analysis was conducted between the two methods. The results showed a correlation coefficient of 0.98, indicating high accuracy of the in-situ test. For field applications, direct measurement of penetration depth is impractical, as it is inherently destructive and requires core extraction from the structural element. To overcome this limitation, one of the key advantages of the cylindrical chamber method was employed—its ability to measure the total volume of water infiltrating the concrete surface over a fixed time under a constant hydraulic head. Statistical analysis of the differences between this study and reference data, using mean absolute percentage error (MAPE) and linear correlation coefficient (R²), showed that the mean infiltration volume differed by less than 10%, with R² = 0.97. These results confirm the low deviation and strong correlation, indicating the accuracy and reliability of the cylindrical chamber test for classifying concrete permeability. In-situ measurements at 11 selected points along the Varzaneh city water supply canal revealed infiltration volumes exceeding 25 mL at all locations, falling within the high-permeability range and signifying substantial water losses. Mercury intrusion porosimetry and SEM imaging further showed that the absence of curing increased porosity and total pore volume by 7% and 69.4%, respectively. Methodology The cylindrical chamber method is a precise and versatile technique for quantifying the permeability of concrete and similar construction materials under laboratory or field conditions. The testing procedure comprised the following steps: 1. Surface preparation: The concrete surface was dried to a constant mass, and all surface contaminants were removed to ensure proper adhesion. 2. Fixture installation: A steel annular ring was bonded to the prepared concrete surface using epoxy adhesive. After full curing of the adhesive, the cylindrical chamber was mounted securely on the metal fixture. 3. Water pressurization: The chamber was filled with de-aired water, and the internal pressure was applied using a calibrated hand-operated lever. The imposed water pressure—5 bar (0.5 MPa)—was continuously maintained and monitored via the gauge installed on the apparatus. 4. Testing duration: Pressure was sustained for 5 hours on the exposed concrete surface. This method allows quantification of water infiltration without sample extraction, thereby preserving the structural integrity of the tested element. Results and Discussion Selected outcomes of the in-situ cylindrical chamber tests on the Varzaneh canal are summarized in Table 6. While numerous measurements were performed along the entire length of the canal, representative results are reported here to illustrate key trends. The findings confirm that the concrete lining of the Varzaneh water supply canal exhibits very high hydraulic permeability, significantly exceeding recommended thresholds. In the evaluated sections, the infiltration volumes surpassed 25 mL, classifying them in the high-permeability range per the adopted criteria. Such elevated permeability is directly associated with excessive seepage losses, contributing to increased water demand and reduced delivery efficiency. These observations strongly suggest that the measured reduction in outflow is not the result of unauthorized water extraction along the canal’s route. Rather, the dominant factor is the inadequate impermeability of the concrete lining, which permits substantial leakage through the canal body. Conclusions - Regression analysis revealed a strong linear correlation (R² = 0.98) between the cylindrical chamber method and the BS EN 12390 8 (British Standard) test, confirming the reliability of the field measurements. This enabled accurate in-situ assessment of the Varzaneh canal’s permeability without inducing structural damage. - Concrete with an infiltration volume < 12 mL is classified as low permeability; 12–25 mL denotes medium permeability, and > 25 mL corresponds to high permeability. The majority of tested points on the Varzaneh canal exceed 25 mL, indicating widespread high-permeability zones. - The substantial difference between inflow and outflow in the canal is primarily attributable to leakage through the concrete lining, rather than unauthorized withdrawals. Consequently, a large proportion of the supplied water fails to reach its intended destination in the city of Varzaneh. | ||
| کلیدواژه‌ها [English] | ||
| Permeability, flow reduction, concrete, in-situ test | ||
| مراجع | ||
|
ACI, ACI (2018); Concrete Terminology, ACI CT-18. American Concrete Institute, Farmington Hills. Alexander, M., Bentur, A., & Mindess, S. (2017). Durability of concrete: design and construction (Vol. 20). CRC Press. ASTM C127-15 (2015); Standard Test Method for Relative Density (Specific Gravity) and Absorption of Fine Aggregate. ASTM International, West Conshohocken, PA. ASTM C128-15 (2015); Standard Test Method for Relative Density (Specific Gravity) and Absorption of Coarse Aggregate. ASTM International, West Conshohocken, PA. ASTM C136-19 (2019); Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates. ASTM International: West Conshohocken, PA, USA. BS EN 12390-8:, (2019). Testing Hardened Concrete. Depth of Penetration of Water under Pressure. Chandrappa, A.K. & Biligiri, K.P. (2016). Comprehensive investigation of permeability characteristics ofpervious concrete: A hydrodynamic approach, Construction and Building Materials, 123, 627-637. DIN 1048-5, (1991). In Testing concrete: testing of hardened concrete (specimens prepared in mould). Kosmatka, S. H., Panarese, W. C., & Kerkhoff, B. (2002). Design and control of concrete mixtures Skokie, IL: Portland Cement Association. Vol. 5420. 60077-1083. Kou, S.C. & Poon, M. (2014). Etxeberria, Residue strength, water absorption and pore size distributions of recycled aggregate concrete after exposure to elevated temperatures, Cement and Concrete Composites, 53, 73-82. Naderi, M. Kaboudan, A. and Kargarfard, K. (2022). Studying the compressive strength, permeability and reinforcement corrosion of concrete samples containing silica fume, fly ash and zeolite. Journal of Structural and Construction Engineering, 8(2), 25-43. Naderi, M., & Kaboudan, A. (2020). Cylindrical Chamber: A New In Situ Method for Measuring Permeability of Concrete with and without Admixtures. Journal of Testing and Evaluation, 48(3), 2225-2241. Naderi, M., & Kaboudan, A. (2021). Experimental study of the effect of aggregate type on concrete strength and permeability. Journal of Building Engineering, 37, 1-11. Naderi, M., & Kaboudan, A. (2021). Investigating the effect of strength, time and amount of water pressure, and direction on concrete permeability. Amirkabir Civil Engineering Journal, 52(9), 2379-2398. Naderi, M., (2010). Determine of concrete, stone, mortar, brick, and other construction materials permeability with cylindrical chamber method, C.a.i.p. office, Editor. Iran. Shen, L., Zhang, L., Yang, X., Di Luzio, G., Xu, L., Wang, H., & Cao, M. (2024). Multiscale cracking pattern-based homogenization model of water permeability in hybrid fiber-reinforced concrete after high-temperature exposure. Journal of Building Engineering, 84, 108643. Siddiqui, M. S., Nyberg, W., Smith, W., Blackwell, B., & Riding, K. A. (2013). Effect of curing water availability and composition on cement hydration. ACI Materials Journal, 110(3), 315-322. Springenschmid, R. (2007). Betontechnologie für die Praxis, 1st ed.; Beuth Verlag GmbH: Berlin, Germany. Taylor, H. F. (1997). Cement chemistry London: Thomas Telford. Boooook. (Vol. 2, p. 459). Teriqet, A., Mohammadi., M., & Medras Y. (2019). Thermodynamic investigation of hydration and chemical shrinkage of cement containing slag. Sharif. J. of Civil Eng, 34(4), 82-57. Wei, J., Chen, Z., Liu, J., Liang, J., & Shi, C. (2023). Review on the characteristics and multi-factor model between pore structures with compressive strength of coral aggregate. Construction and Building Materials, 370, 130326. Yildirim, M., & ÖZHAN, H. B. (2023). Effect of permeability-reducing admixtures on concrete properties at different cement dosages. Journal of Innovative Science and Engineering, 7(1), 48-59. Zeng, W., Wang, W., Pan, J., & Liu, G. (2023). Effect of steel fiber on the permeability of freeze-thaw damaged concrete under splitting tensile and compressive loads. Journal of Building Engineering, 80, 108086. Zeng, W., Zhao, X., Zou, B., & Chen, C. (2023). Topographical characterization and permeability correlation of steel fiber reinforced concrete surface under freeze-thaw cycles and NaCl solution immersion. Journal of Building Engineering, 80, 108042. Zhang, G., Zheng, H., Wei, X., Li, Z., Yan, Z., & Chen, X. (2024). Concrete mechanical properties and pore structure influenced by high permeability water pressure. Developments in the Built Environment, 100385. Zhang, J., Zhou, L., Nie, Q., Wu, H., & Wu, L. (2024). Effects of calcium sulfate whiskers and basalt fiber on gas permeability and microstructure of concrete. Construction and Building Materials, 411, 134369. | ||
|
آمار تعداد مشاهده مقاله: 17 تعداد دریافت فایل اصل مقاله: 14 |
||