اندازه‌گیری تغییرات روزانه دمای آب و هوای داخل مخازن نیمه‌پر ذخیره آب با جداره بتن و بتن متخلخل

نوع مقاله : علمی - پژوهشی

نویسندگان

1 گروه مهندسی آب و سازه های هیدرولیکی، دانشکده مهندسی عمران، دانشگاه سمنان، سمنان، ایران

2 استادیار دانشکده عمران دانشگاه سمنان

3 استاد، دانشکده مهندسی عمران، دانشگاه سمنان، سمنان، ایران

4 دانشکده مهندسی عمران دانشگاه سمنان، سمنان، ایران

چکیده

امروزه دسترسی به آب شرب سالم در اکثر مناطق خشک و نیمه خشک جهان چالشی مهم می‌باشد. به دلیل ارزان بودن مواد اولیه ساخت مخازن بتنی ، این نوع از سازه‌ها در بسیاری از مناطقی که با مشکل آبی مواجه هستند، مرسوم می‌باشد. این تحقیق با بهره-گیری از ایده آب‌انبارهای قدیمی، که تا سه چهار دهه پیش نقش مهمی در ذخیره آب مناطق دور افتاده، روستایی و شهرهای کوچک داشتند، و تأثیرگذاری آنها در کاهش و یا افزایش دمای آب، به بررسی کاربرد بتن متخلخل در جداره مخازن ذخیره آب و تأثیر عبور هوا از محیط متخلخل این بتن می‌پردازد. برای بررسی بیشتر، از افزودنی لیکا به مقدار 5 درصد وزنی سنگدانه‌ها نیز استفاده گردید و از این تیمار و تیمار شاهد سه تکرار ساخته شد. اندازه‌گیری روزانه دما و رطوبت نسبی محیط به وسیله سنسور مربوطه و دمای آب و هوای داخل مخازن با دو سنسور دمایی، یکی در وسط قسمت آب و یکی در وسط قسمت هوای مخازن در گرمترین ساعت روز (14:30) در فصول بهار و تابستان 1398 انجام شد. نتایج نشان داد که میانگین دمای آب تیمار لیکا نسبت به میانگین دمای آب تیمار شاهد کمتر می‌باشد. میانگین دمای هوای تیمار شاهد نسبت به تیمار لیکا بیشتر بود؛ ولی اختلاف ناچیزی داشتند و همواره میانگین دمای آب و هوای داخل مخازن از میانگین دمای محیط کمتر می‌باشد . همچنین، پارامترهای فیزیکی بتن متخلخل (تخلخل، نفوذپذیری و مقاومت فشاری) در این پژوهش مورد بررسی قرار گرفت. نتایج نشان داد که مقاومت فشاری و تخلخل تیمار لیکا بیشتر از تیمار شاهد و نفوذپذیری با اختلاف بسیار کمی از تیمار شاهد کمتر می‌باشد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Daily variation measurement of water and air temperatures inside the semi-full water storage tanks which have solid and porous concrete walls

نویسندگان [English]

  • Milad Vahdatifar 1
  • Hojat Karami 2
  • Sayed-Farhad Mousavi 3
  • Saeed Farzin 4
1 Department of Water Engineering and Hydraulic Structures, faculty of Civil Engineering, Semnan University, Semnan, Iran
2 Faculty of Civil Engineering, Semnan University, Semnan, Iran
3 Professor, Faculty of Civil Engineering, Semnan University, Semnan, Iran
4 Department of Water Engineering and Hydraulic Structures, Faculty of Civil Engineering, Semnan University, Semnan, Iran
چکیده [English]

Nowadays, access to safe drinking water is a major challenge in most arid and semi-arid regions of the world. Due to the low cost of raw materials for construction of concrete tanks, these types of structures are common in many areas where water problems are encountered. This study explores the use of porous concrete by utilizing the idea of old water storage tanks (Ab-Anbars), which played an important role in water storage for remote areas, rural and small towns until three to four decades ago, and their effect on reducing or increasing water temperatures. At the wall of the water storage tanks, effect of air passage through the porous concrete on the water inside the tanks is studied. For further investigation, LECA (5% by weight of aggregates) was used as an additive to porous concrete and 3 replicates of this treatment and control treatment were made. Daily ambient temperature and humidity were measured by the respective sensors, and inside temperature of the tanks was measured with two sensors, one in the middle of the stored water and one in the middle of the open space of the tanks, in the warmest hour of the day (14:30 pm) in spring and summer of 2019. Results showed that mean water temperature of LECA treatment was lower than mean water temperature of control and mean air temperature of control treatment was higher than mean air temperature of LECA treatment. Mean air and water temperatures were always less than mean ambient temperature. Also, the physical parameters of porous concrete (i.e., porosity, permeability and compressive strength) were investigated in this study. Results showed that the compressive strength and porosity of LECA treatment were higher than the control and its permeability was lower than the control.

کلیدواژه‌ها [English]

  • -Concrete tanks
  • Porous concrete
  • Porosity
  • Permeability
  • Compressive strength
  • Additive
  • Water temperature
  • Air temperature
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