تاثير سرباره‌ي فولادسازي در خصوصيات مقاومتي و پايداري حجمي خاك‌هاي رسي تثبيت‌شده با آهك

Influence of Basic Oxygen Slag (BOS) on Strength and Volumetric Stability Characteristics of Lime Stabilized Kaolinite

در اين نوشتار، تاثير سرباره‌ي توليدي كارخانه‌ي ذوب‌ آهن اصفهان در تورم، حدود اتربرگ و مقاومت فشاري كايولينيت و كايولينيت تثبيت‌شده با آهك تحت شرايط خشك و پس از تورم (اشباع‌شدن) مورد بررسي قرار گرفته است. بدين منظور مقادير 1، 3 و 5 درصد آهك و 10، 15و20 درصد سرباره با كايولينيت مخلوط و پس از 1، 7، 28 و90 روز عمل‌آوري تحت دماي 35 درجه‌ي سانتي‌گراد، نمونه‌ها مورد آزمايش قرار گرفته‌اند. نتايج نشان مي‌دهد كه تورم، مقاومت فشاري و خصوصيات خميري نمونه‌هاي تثبيت‌شده با آهك و سرباره به‌صورت هم‌زمان در مقايسه با نمونه‌هاي تثبيت‌نشده و تثبيت‌شده با آهك به مقدار چشم‌گيري بهبود يافته است. بهبود اين خصوصيات در نمونه‌هاي تثبيت‌شده، به مقدار سرباره، آهك و مدت زمان عمل‌آوري بستگي دارد. ميزان تورم و مقاومت نمونه‌هاي كايولينيت تثبيت‌نشده به ترتيب 85/4? و 8/4 كيلوگرم بر سانتي‌متر مربع و نمونه‌هاي تثبيت‌شده با 5? آهك و 20? سرباره به ترتيب 14/0? و 58 /46 كيلوگرم بر سانتي‌متر مربع تعيين شده است، كه بيان‌گر3527? كاهش در تورم و 970? افزايش در مقاومت است.

Rapid development and industrialization has produced large quantities of waste. Much of this waste does not have any effective use, and its disposal has become more difficult and expensive because of the increasingly stringent environmental regulations and the shortage of suitable nearby disposal sites. It has been observed that some of this waste has high potential and can be gainfully utilized in other industries. To use industrial waste will not only help in solving environmental pollution problems associated with its disposal but also help in the conservation of natural resources. Blast furnace slag and steel making slag is produced during the iron and steel making process. These materials are widely utilized in construction industries all over the world. Use of these by-products depends on their chemical composition and physical properties. Despite some industrial uses of blast furnace slag in Iran, it is still considered a by-product requiring storage. In this article, the effect of basic oxygen slag (BOS) on the swelling and shrinkage characteristics of clay soil has been investigated. Kaolinite samples have been treated with 1, 3 and 5% lime and 10, 15 and 20% BOS slag. Samples have been cured at 35?C for periods of 1, 7, 28 and 90 days, after which, they were subjected to swelling, unconfined compressive strength, and liquid limit, plastic limit and shrinkage limit tests. Results showed that the concurrent addition of lime and BOS slag to kaolinite, compared to lime treated kaolinite samples, significantly reduces their swelling potential. The unconfined compressive strength of lime/BOS slag treated kaolinite samples also showed a significant increase when compared to lime only treated samples. The amount of swelling reduction or the increase in unconfined compressive strength was found to be a function of the percentage of lime and BOS slag addition, as well as the curing period.