STABILIZATION OF EXPANSIVE SOIL USING MILL SCALE

Y.I.Murthy 1*

1*Civil Engineering Department, IES, IPS Academy, Indore *Corresponding Author: e-mail: yogesh_murthy@rediffmail.com, Tel +91-9009648616,

Abstract The present paper deals with the evaluation of the mechanical properties of black cotton soil mixed with mill scale in varying proportions and comparing the same with the results of pure black cotton soil. The mechanical properties of mill scale and black cotton soil are individually determined first and then the two are combined in varying proportions. The properties like plastic limit, CBR and Permeability of the same are evaluated. It is found that mixing mill scale in varying proportions increases the permeability of the soil, strength characteristics and decreases the plasticity. Keywords: Black cotton soil, Mill Scale, permeability, CBR. 1. Introduction Innovations for utilization of wastes for developing products, which are useful to the society are gaining importance day-by-day. The present investigation deals with a similar concept of using milled scale in soil to modify its properties. Mill scale is a metal industry waste which is produced in tons and poses grave disposal problems. Milled scale is mainly iron oxide formed in the surface of steel during casting, hot rolling and reheating of steel. On an average, every year, one single steel processing unit produces about 7000 to 8000 tons of mill scale. Though the physical, chemical and mechanical properties of mill scale depends on the processing technique, handling methods, properties of steel and exposure to atmosphere, the main ingredients of milled scale is iron oxides-mainly ferric. As such, mill scale is used in making flux for welding electrode coating, in Thermit welding and as a source of Ferro-alloy. Adams, 1979, and Daiga, et al., 2002[1] reported the recycling process of steel mill scale in sintering furnaces or hearths. Pradip et al [2] used mill scale for the production of alinite cement. Young; Rom D. and Norris; David, [3] used mill scale for forming cement clinkers that may have hydrocarbons associated with them. Abdul-Majeed Azad et al. [4] proposed a method to process and convert the purer form of mill scale into nano scale particles, which could be used for hydrogen fuel cell, medical imaging and water remediation applications. Stefania Tomasiello, Matteo Felitti [5] presented preliminary results of using EAF slag in self compacting concrete. The EAF was used as medium aggregate and excellent results were obtained for the fresh properties and compressive strength of SCC. Journals are flooded with similar kind of research works which involve substituting the conventional ingredients of concrete and cement mortar with industrial wastes. 2. Stabilization Of Soil Chandrasekaran et al [6] studied the swelling properties of black cotton soil in a geotechnical centrifuge under 1-g with different surcharge stresses and obtained close agreements between the field and laboratory results. Poh [7] investigated the stabilization of English China clay and Mercia mudstone using BOS slag fines. Improved strength and durability combined with reduction in expansion was obtained. Punthutaecha et al. [8] evaluated the changes in volume of sulfate rich expansive soils stabilized using class F fly ash, bottom ash, polypropylene fibers, and nylon fibers. The isolated stabilizer treated and combined ash-fiber stabilized soils were tested for volumetric shrinkage strain, volumetric free swell and vertical swell pressure test. It was finally concluded that ash stabilizers showed improvements in reducing swelling, shrinkage, and plasticity characteristics by 20–80% whereas fibers treatments resulted in varied improvements. S.E. Campbell [9] studied and described how the two dominating cyanophyte species,Microcoleus vaginatus andM. Chthonoplastes showed stromatolitic features thereby preventing the mobility of sand and clay in Utah and Colorado. T. Abadjieva [10] presented a paper for the stabilization of low cost roads using con-aid as a chemical stabilization agent. K.J. Osinubi et al.[11] investigated the effect of Bagasse Ash (BA) admixture on the engineering properties of lime treated black cotton soil. Black cotton soil is classified as A-7-6 or CH respectively. It was shown that the OMC increases while the MDD decreases at the standard Proctor compaction energy. The CBR value of such a soil met the standards of sub-grade materials. S.S.Quadri et al. [12] studied stabilization of black cotton soil with respect to the

Y.I.Murthy et al. / International Journal of Engineering Science and Technology (IJEST)

ISSN : 0975-5462 Vol. 4 No.02 February 2012 629

permeability aspects for use in engineered landfills. It was concluded that the use of sodium bentonite and lime improved the permeability of the black cotton soil and this alternative composite material could be used for landfill cover.

3. Mill Scale Mill scale is a magnetic material consisting of iron in a typical range of 93-95%. Hence, the chemical composition of mill scale is similar to hematite; magnetite or wüstite. The X-ray diffraction analysis showed that the mineralogical phases in mill scale could be Hematite Fe2O3, Magnetite Fe3O4 and Wüstite, FeO. The material is porous, hard and brittle and every year almost 18-20 million metric tons of this material is produced. Most of the material is dumped in landfills. While some part of the material is used in Thermit welding, concreting and in ceramic industry. Though, dumping mill scale in landfills creates serious environmental issues, it would prove to be a boon if mixed with black cotton soil as a mixing 15% of mill scale to black cotton soil has resulted in prominent changes in permeability and plasticity properties. Thus, a mill scale stabilized road can use black cotton soil as an embankment or sub grade layer.

3.1 Physical Properties Of Mill Scale Mill Scale is a fine blue-grey material and possesses magnetic properties due to the presence of iron oxides. The specific gravity of the material is 2.03 and water absorption is 0.75%. 3.2 Chemical Properties Of Mill Scale

The typical chemical composition of mill scale is as under: Chemical Typical % Fe2O3 93.61 MnO 1.53 TiO2 0.014 Si02 1.87 MgO 0.28 CaO 0.111 Na2O 0.013 Al2O3 0.099

4. Results and Discussions: The following tests were conducted on black cotton soil:

1. Plastic Limit, 2. CBR and 3. Permeability.

The constant head permeability test was conducted and the permeability was found to be 1.168 X 10-4 cm/sec. the plastic limit for the soil was 35.71 %. The CBR value of the soil was 3.2%. 4.1 Plastic Limit Test

Sr. no. Sample Plastic Limit (%)

1. Plain soil 35.71 2. Soil + 3% mill scale 35.04 3. Soil + 5% mill scale 34.11 4. Soil + 7% mill scale 32.58 5. Soil + 10% mill scale 31.30 6. Soil + 12% mill scale 30.60

Y.I.Murthy et al. / International Journal of Engineering Science and Technology (IJEST)

ISSN : 0975-5462 Vol. 4 No.02 February 2012 630

4.2 CBR Test The CBR test of plain black cotton soil and using mill scale was conducted. The results showed progressive increase in the value of CBR with the increase in percentage of Mill Scale.

4.3 Permeability Test Constant head permeability test was conducted on plain soil and mixing 3, 5, 10 and 15 percent of mill scale in the sample. The permeability value increased rapidly in the region of 5-10% after which the increase was comparatively less.

Sr. no.

Sample CBR (%)

1. Plain soil 3.2 2. Soil + 3% mill scale 5.7 3. Soil + 5% mill scale 6.5 4. Soil + 7% mill scale 7.8 5. Soil + 10% mill scale 9.2 6. Soil + 12% mill scale 9.7 7. Soil + 15% mill scale 9.9

Y.I.Murthy et al. / International Journal of Engineering Science and Technology (IJEST)

ISSN : 0975-5462 Vol. 4 No.02 February 2012 631

5. Conclusions: Significant and desirable results have been found by adding the metal industry waste to the black cotton soil and promising results for use of black cotton soil as embankment material have been found. From the above tests and results, the following conclusions can be drawn:

i. The CBR value of black cotton soil mixed with 15% mill scale increased three times that of plain black cotton soil.

ii. The permeability value of black cotton soil increased manifolds by increasing the percentage of mill scale.

iii. The plasticity of the black cotton soil decreased from 35.71% to 30.60% by adding 12% of mill scale.

References: [1] Adams, C.J. (1979) "Recycling Of Steel Plant Waste Oxides - A Review" CANMET Report [2] Pradip, D. Vaidyanathan, P. C. Kapur and B. N. Singh, (1990), "Production and properties of alinite cements from steel plant wastes",

Cement and Concrete Research, Volume 20, Issue 1, January, Pages 15-24. [3] Young; Rom D. and Norris; David, (2004) "Process for using mill scale in cement clinker production", US Patent No. 6709510. [4] Azad A.M. Sathees Kesavan, Sirhan Al-Batty,(2008),” Redemption of Micro scale Mill waste into commercial Nano scale Asset”,Key

Engineering Materials, volume 380, pages-229-255 [5] Stefania Tomasiello, Matteo Felitti ,(2010),” EAF slag in self-compacting concretes”, [6] Facta Universitatis Series: Architecture and Civil Engineering Vol. 8, No 1, 2010, 13 - 21 [7] Gadre, A D ,Chandrasekaran, V S,(1995)” Swelling of black cotton soil using centrifuge modeling”, Journal of Geotechnical

Engineering, Vol 120,issue no.5,pg914-919 [8] Poh, H Y,Ghataora, Gurmel S,Ghazireh, Nizar,(2206),” Soil Stabilization Using Basic Oxygen Steel Slag Fines”,Journal of materials

in Civil Engineering,vol 18 issue no 2,pg229-240 [9] Punthutaecha, Koonnamas,Puppala, Anand J,Vanapalli, Sai K,Inyang, Hilary I,(2006),” Volume Change Behaviors of Expansive Soils

Stabilized with Recycled Ashes and Fibers”, Journal of materials in Civil Engineering, vol 18 issue no 2,pg295-306 [10] Campbell S.E.,(1979),”Soil stabilization by a prokaryotic desert crust: Implications for Precambrian land biota”, Origin of Life and

Evolution of Bio-sphere, vol 9, pg.335-348 [11] Abadjieva T.” Chemical Stabilisation For Low Cost Roads In Botswana” [12] Osinubi K.J., Ijimdiya T.S., Nmadu I (2009).”Lime Stabilization of Black Cotton Soil Using Bagasse Ash as Admixture.” Advanced

Materials Research(Volumes 62 – 64) [13] 3-10 [14] S.S. Quadri, Laxmikantha H.,M. R. Patil (2008)” Suitability of Industrial Process Wastes as Alternative Materials for Landfill

Covers.” The 12th International Conference of International Association for Computer Methods and Advances in Geomechanics (IACMAG)

Y.I.Murthy et al. / International Journal of Engineering Science and Technology (IJEST)

ISSN : 0975-5462 Vol. 4 No.02 February 2012 632