روش های اشباع سازی سنگ های انحلال پذیر (با تاکید بر سنگ های ژیپس-انیدریت)

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه زمین شناسی، دانشکده علوم پایه، دانشگاه بوعلی سینا، همدان، ایران

2 گروه زمین شناسی، دانشکده علوم پایه، دانشگاه بوعلی سینا، همدان ایران

3 گروه زمین شناسی- دانشکده علوم پایه- دانشگاه بین المللی امام خمینی(ره)

چکیده

به منظور شناسایی رفتار طبیعی سنگ ها در شرایط رطوبتی مشابه با رطوبت واقعی، معمولاً از دو روش اشباع سازی، تحت فشار اتمسفر و یا تحت فشار خلاء استفاده می گردد. در به کارگیری روش فشار خلاء، مقادیر دو پارامتر فشار خلاء (Pvac) و زمان خلاء (Tvac) از پارامترهای موثر بر اشباع سازی نمونه ها می باشند. در این مطالعه روش اشباع سازی سنگ، به ویژه سنگ های انحلال پذیر مانند ژیپس- انیدریت مورد بررسی قرار گرفته است. نتایج این بررسی بر حسب حساسیت سنجی برای چهار پارامتر فشار خلاء خشک (Pvac(dry))، فشار خلاء تر (Pvac(wet))، زمان خلاء خشک و زمان خلاء تر ((Tvac(wet), Tvac(dry) مورد بررسی قرار گرفته است. نتایج به دست آمده نشان می دهد که با افزایش Pvac(wet)، درصد جذب آب افزایش یافته و به طور کلی نمونه ها بعد از چهار روز اعمال خلاء تر به بیش از 95 درصد از افزایش وزن نهایی خود خواهند رسید و در عمل می توان آنها را اشباع کامل در نظر گرفت. اگر قبل از فشار خلاء تر، فشار خلاء خشک به نمونه ها اعمال گردد، افزایش وزن بیشتر نمونه ها بعد از افزودن فشار خلاء تر به وقوع خواهد پیوست. نتایج این پژوهش نشان که اعمال 5/0- آتمسفر فشار خلاء خشک به مدت 5 ساعت و متعاقبا اعمال 5/0- آتمسفر فشار خلاء تر به مدت 96 ساعت، موجب حصول نتیجه ایده آلی در اشباع سازی این گونه سنگ ها خواهد گردید.

کلیدواژه‌ها


عنوان مقاله [English]

Saturation Procedures of Soluble Rocks (Emphasizing on Gypsum-Anhydrite Rocks)

نویسندگان [English]

  • Seyed Davoud Mohammadi 1
  • Mohammad Reza Rahimi 2
  • Alireza Taleb Beydokhti 3
1 Dep. of Geology, Faculty of Sciences, Bu-Ali Sina University, Hamedan, Iran
2 Department of Geology, Faculty of Sciences, Bu-ali Sina University, Hamedan, Iran
3 Department of geology, Faculty of science, Imam Khomeini international university
چکیده [English]

To identify natural behavior of rocks under the similar moisture conditions, two saturation methods of under atmospheric pressure conditions or vacuum pressure are usually used. In the method of vacuum pressure, the values of vacuum pressure Pvac as well as the time of applying this pressure Tvac are two effective parameters. In this study, the saturation method of rock, especially soluble ones such as gypsum and anhydrite, have been studied. The results of the experiments were analyzed in terms of sensitivity for four parameters of dry vacuum pressure Pvac(dry), wet vacuum pressure Pvac(wet) and the time of applying each one (Tvac(wet), Tvac(dry)). The results showed that by increasing Pvac(wet), the percentage of water absorption has been increased and the samples generally gain more than 95% of their increased weight after 4 days of applying wet vacuum and they can be practically assumed to be saturated. Applying dry vacuum Pvac(dry) before wet vacuum Pvac(wet), increases the weight of most samples after applying Pvac(wet). In case of gypsum-anhydrite rocks, the experiment showed that applying dry pressure equivalent to -0.5 atmospheres (atm) and to 5 hours (Pvac(wet) = -0.5 atm, Tvac(dry)) = 5h) propose ideal results.

کلیدواژه‌ها [English]

  • Wet and dry vacuum pressures
  • Sensitivity analysis
  • Rock moisture
  • Gachsaran formation
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