WASTE NOT, WANT NOT


RECYCLED TYRES AND TILES FOR SOIL STABILISATION AND ENGINEERED MATERIAL PRODUCTION


By Aminaton Marto, Mohammed Ali Al-Bared and Zahiraniza Mustaffa With the circular economy agenda


promulgated worldwide to reduce waste and carbon footprint, our built environment sector needs to reduce, reuse and recycle materials. For example, for soil stabilisation, instead of using virgin materials, we can use recycled tiles and tyres; in the production of new material such as the engineered concrete, we can substitute cement or aggregate with shredded tyres or powdered tiles.


If the question is about quality, contrary to commonly-held beliefs, recycled materials are actually not secondary and, in some cases, they even improve the engineering properties. Research shows, for example, that soft soils modified using


these materials can withstand


heavy loads and become more suitable for construction.


Image by sandsun


SOFT SOILS Soft soils have low shear strength and engineering properties that do not meet design requirements, as well as exhibit excessive settlement when loaded. Thus, their poor physical characteristics are not suitable for foundation or any construction applications. Marine clay


and peat are two types of soft soils, and some clays and peat exhibit expansive properties—swelling when gaining water and shrinking when drying out.


Soft soils are prevalent in many parts of Malaysia and they should be either removed or treated before any loading or structure is placed on them. Soil stabilisation methods to increase soft soils’


load-bearing capacity include


addition of fillers, compaction or preloading to improve density; electro- osmosis or dewatering to control the pore water pressure; and chemical treatment and grouting to increase the bonding of the soil particles.


Traditional Additives Choosing the best stabilisation method for treating soft soils depends largely on the soil’s characteristics, purpose of treatment and the required soil strength. Various treatment methods have been introduced in the field of geotechnical engineering over the years, such as using chemical additives. Cement is perhaps one of the oldest and the most common additives to improve soil’s strength and properties. Lime is also


19


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92  |  Page 93  |  Page 94  |  Page 95  |  Page 96  |  Page 97  |  Page 98  |  Page 99  |  Page 100  |  Page 101  |  Page 102  |  Page 103  |  Page 104  |  Page 105  |  Page 106  |  Page 107  |  Page 108  |  Page 109  |  Page 110  |  Page 111  |  Page 112