VOL. 9, NO. 10, OCTOBER 2014 ISSN 1819-6608 ARPN Journal of Engineering and Applied Sciences © 2006-2014 Asian Research Publishing Network (ARPN). All rights reserved. www.arpnjournals.com 1744 CLAY SOIL STABILIZATION WITH LIME EFFECT THE VALUE CBR AND SWELLING Gati Sri Utami Department of Civil Engineering, Adhi Tama Institute of Technology Surabaya, Indonesia E-Mail: fita.fina3@gmail.com ABSTRACT Subgrade was a very important part to support all construction loads on it. If the clay subgrade that had unfavorable properties, such as low CBR, the high swelling when applied to the construction of the road subgrade soil would produce a soil that is easily damaged. For that, if used in the construction of CBR value should be towering so that it can withstand a load on it. The swelling would reduce the volume of soil that is stable when it rains the soil is not swollen, otherwise when the dry season does not shrink too high. Ground improvement methods used in this study was stabilization of lime-soil, using a mixture of percentage 5%, 10% and 15% of the lime. Tests performed on the Atterberg limits, Compaction (Standard Proctor Test), C.B.R laboratory, and Swelling. The results of the study about a large percentage of the value of lime plasticity (liquid limit, plasticity index) decreased with the increasing compaction. The average CBR value is increased for the natural soil to percentage 5% and 10% of lime, while the percentage of 15% decreased. For the swelling, the percentage of 15% lime with 24 hours immersion showed 45.28% increase in swelling of the normal soil (i.e. 31.67% to 17.33%) So in general the best for clay soil stabilization is Pakuwon area where the addition of 10% lime CBR values obtained optimum and could reduce swelling value. Keywords: lime, stabilization, CBR, swelling. INTRODUCTION Background Subgrade is a very important part to support all construction loads on it. If the clay subgrade that has properties that are not profitable, such as CBR (California Bearing Ratio) low and high swelling so that when applied to the construction of a dirt road, the land base will easily damage. For that if used in the construction of CBR value should be towering so that it can withstand a load on it. The swelling will reduce the volume of soil that is stable when it rains he is not swollen, otherwise when the dry season does not shrink too high so that the cracks in the road can be reduced or eliminated [[1], [2], and [3]]. The purpose of soil stabilization is to improve the physical properties, mechanical and increase the carrying capacity of the land that will be taken into account in the planning pavement. Therefore, soil stabilization requires the planning and implementation of an accurate method of soil change for the better. Lime has been known as one of the good soil stabilization materials, especially for clay stabilization properties that have a large swelling and generally contain high levels of clay, but its swelling properties will be much reduced, even eliminated, if the soil mixed with lime. The presence of Ca2 + cations on the elements of lime can provide bonding between the larger particles that expands on soil properties [[4] and [5]]. From the results conducted by [6], there is an increase in CBR and decrease swelling of the subgrade soil using a method of stability with soil and lime, soil samples from Spring Mulyo and lime from Purwodadi original soil + lime by the percentage of 0%, 5%, 8%, 10%, 12% lime. CBR did not submerged: the percentage of 10% lime, obtained an increase in CBR of 11.8% to 22.1%, but the percentage of 12% lime CBR decreased slightly to 22%. CBR submerged: the percentage of 10% lime, obtained an increase in the CBR from 2.45% to 7.6%, but for 12% the percentage of lime CBR decreased slightly to 7.58%. Swelling decreased with increasing percentage of lime in other words, the more the percentage of lime small swelling that occurs. Liquid limit and plastic limit do not directly provide the value that can be used in the calculation. Limits used in this experiment are the Atterberg limits the description will represent the properties of the land concerned. High liquid limit soil usually has a poor technical nature, which is a low carrying capacity, towering and difficult compressibility in compaction. For various of soil, Atterberg limits can be linked empirically with other properties, such as shear strength or index compression and so on [[7] and [8]]. Compaction is a process by which the air in the pores of the soil removed by mechanical means to achieve the density requirements. Soil density is usually measured in dry unit weight, not by the number of pores. The dry unit weight great its mean that the number of smaller pores and higher compaction. Swelling is the process of entry of water into the pores which causes swelling of the soil volume. The amount of swelling is the ratio between height changes after immersion of the original height of the sample is usually presented in the form of percent [[7] and [8]]. C.B.R. was developed as a way to assess the strength of the foundation soil, so that we can know the materials that will be used for the manufacture of pavement. CBR values calculated at the rate of penetration of 0.1 "and 0.2" by dividing each penetration load standards 3000 and 4500 pound load obtained from experiments on a wide crushed stone considered to have a