TY - JOUR T1 - Determination of volume change characteristics and effects of polymer and discrete short polypropylene fiber (PP-fiber) on saline clayey soils TT - تأثیر تثبیت با آهک و پلیمر و تسلیح با الیاف پلیمری بر رفتار تغییر حجمی خاکهای رسی شور JF - jeg JO - jeg VL - 4 IS - 1 UR - http://jeg.khu.ac.ir/article-1-346-en.html Y1 - 2010 SP - 827 EP - 854 KW - Saline clayey soil KW - volumes change behavior KW - Swelling KW - Consolidation KW - Stabilization KW - Lime KW - Epoxy –resin polymer KW - polypropylene fiber N2 - Saline soils are of challengeable soils that may cause many problems in civil engineering projects. In this study, volume change behaviour of saline soils and also the effect of improvement and reinforcement on them have been investigated using laboratory tests as well as consolidation test, swelling pressure test and free swelling test. The case study is Amirkabir Highway which connects the cities Qom and Kashan.  Fifty four kilometer of this highway was deformed like waves due to existence of saline soils. The laboratory investigations showed that the studied soil has a considerable swelling potential which appears to be the main cause of damage to the highway pavement, therefore it is decided on improving the subsoil condition. The research program comprises of studying volume change behavior of saline soil, stabilized with lime and epoxy – resin polymer and reinforced with polypropylene fiber. Afterwards, results for two cases of stabilized and non-stabilized samples have been compared. According to the results, the main cause of swelling is soil disturbance and structure destruction of initial soil composition. Considering all of test conditions, it is appeared that, although lime is a traditional stabilization material but is economic for the most geotechnical projects and usage of polymer is suggested only in special applications due to its rapid setting M3 ER -