ببررسی اثر زئولیت بر مقاومت خاک ماسه‌ای بابلسر تثبیت‌ شده با سیمان با استفاده از آزمایش مقاومت فشاری تک محوری

نویسندگان
1 دانشگاه بابل
2 دانشگاه صنعتی بابل
چکیده
ماسه‌های سیمانی به‌ عنوان یکی از موضوعات اقتصادی و زیست ‌محیطی در تثبیت خاک شناخته می‌شوند. در برخی موارد ترکیبی از سیمان و ماسه با سایر مواد از جمله فیبر، شیشه، نانو‌ذرات و یا زئولیت می‌تواند به‌ طور مؤثر در تثبیت خاک در جاده ‌سازی استفاده شود. در این بررسی زئولیت به‌ عنوان یکی از مواد افزودنی به سیمان و اثرات آن بر مقاومت فشاری تک محوری مورد ارزیابی قرارگرفته است. در این راستا از زئولیت نوع معدنی کلینوپیلولیت، سیمان تیپ II نکا و ماسه بابلسر به عنوان خاک پایه استفاده شد. تعداد 144 آزمایش مقاومت فشاری تک محوری بر روی طرح اختلاط 24 حالت سیمان و زئولیت شامل درصد سیمان‌های مختلف 2، 4، 6 و 8 درصد وزن خشک کل نمونه و درصد‌های جایگزینی 0، 10، 30، 50، 70 و 90 زئولیت نسبت به سیمان با تراکم نسبی‌های 50، 70 و 85 درصد در مدت عمل‌آوری 7 و 28 روز انجام شد. نتایج نشان می‌دهد که با جایگزینی 30% زئولیت به‌ جای سیمان نسبت به نمونه‌های بدون زئولیت، مقاومت فشاری تک محوری، به میزان 20 تا 78 درصد افزایش می یابد. همچنین در این فرآیند کرنش گسیختگی نمونه ها نیز زیاد می‌شود. نرخ افزایش مقاومت فشاری تک محوری برای نمونه‌های با درصد سیمان‌های بالاتر و تراکم کمتر، بیشتر است. همچنین نتایج حاکی از ارتباط توانی مقاومت فشاری تک محوری با پارامترهای وزنی سیمان، زئولیت و تخلخل (چند جمله‌ای از وزن‌های سیمان و زئولیت/تخلخل) می‌باشد.

کلیدواژه‌ها

موضوعات


عنوان مقاله English

Evaluation of Zeolite Effect on Strength of Babolsar Sand Stabilized with Cement using Unconfined Compression Test

نویسنده English

Hossein MolaAbasi 1
1 Babol University of technology
چکیده English

The lack of accessibility of high quality materials and the increased costs associated with the use of these materials will finally demand engineers to use local soils. In such cases, ground improvement performed reasonably in many conditions. Ground improvement can be defined as the procedure of increasing shear strength parameters and decreasing the permeability and compressibility of the soil. Different methods can be used to improve the geotechnical properties of the problematic soils such as loose sand that one of them is using additives. The stabilization of soils with cement is an attractive technique due to economic and environmental issues and avoiding the use of borrow materials from elsewhere. Cementation of sand results in increased brittle behavior as peak compression strength increases. The compressive strength of artificially cemented soils has been studied in the past by several investigators.A number of studies have also reported on the influence fiber, glass, fly ash, silica fume and nono particle on the mechanical behavior of cemented sands .However, to the author’s knowledge, there has been a little effort devoted to the research on the use of pozzolans such as natural zeolite as an addictive material to the cemented sands. Natural zeolite, an extender, has been investigated for use as cement and concrete improver by some researchers.

It is widely known and well emphasized that the cemented sand is one of economic and environmental topics in soil stabilization. In some instances, a blend of sand, cement and other materials such as fiber, glass, nano particle and zeolite can commercially available and effectively used in soil stabilization in road construction. In this investigation, zeolite and its effect on unconfined compression studied as one of addictive material to cement. Therefore, cilinopiolite kind of zeolite, Neka cement type II and Babolsar sand are used. A total number of 144 unconfined compression tests were carried out on 24 combination type of cement and zeolite include different cement percentages 2, 4, 6 and 8 percent of total dry weight of samples and replacement percent’s of 0, 10, 30, 50, 70 and 90 zeolite with cement based on 50,70 and 85% relative densities in7 and 28 days curing times. Results show that in 28 day curing time, by replacement percentage of 30 zeolite material by cement, the unconfined strength increased 20 to80% in comparison with cemented samples by increasing shear strain. For higher cement content and less compacted blends, these improvement rates are more. At the end, a power function fits presented to relate unconfined compressive strength (UCS) and zeolite-cement-soil parameters (porosity (n) and voids/ polynomial model of cement and zeolite voids).It is widely known and well emphasized that the cemented sand is one of economic and environmental topics in soil stabilization. In some instances, a blend of sand, cement and other materials such as fiber, glass, nano particle and zeolite can commercially available and effectively used in soil stabilization in road construction. In this investigation, zeolite and its effect on unconfined compression studied as one of addictive material to cement. Therefore, cilinopiolite kind of zeolite, Neka cement type II and Babolsar sand are used. A total number of 144 unconfined compression tests were carried out on 24 combination type of cement and zeolite include different cement percentages 2, 4, 6 and 8 percent of total dry weight of samples and replacement percent’s of 0, 10, 30, 50, 70 and 90 zeolite with cement based on 50,70 and 85% relative densities in7 and 28 days curing times. Results show that in 28 day curing time, by replacement percentage of 30 zeolite material by cement, the unconfined strength increased 20 to80% in comparison with cemented samples by increasing shear strain. For higher cement content and less compacted blends, these improvement rates are more. At the end, a power function fits presented to relate unconfined compressive strength (UCS) and zeolite-cement-soil parameters (porosity (n) and voids/ polynomial model of cement and zeolite voids).

کلیدواژه‌ها English

Stabilization
Cement
Zeolite
Unconfined compression strength
Polynomial
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