Improvement of Problematic Soil Using Crumb Rubber Tyre

Abstract

Construction on problematic soil that has low bearing capacity, low shear strength, high compressibility, and high water-content will interfere with the smooth construction process and will affect time and cost due to repetitive maintenance. Pavement built on problematic soil as its subgrade is exposed to pavement failures, such as fatigue cracking, longitudinal cracking, and pumping, owing to swelling or shrinkage due to moisture variation and differential settlement. Therefore, improvement of the ground needs to commence so as to improve its load bearing capacity, in order to sustain the load on top of it. Consequently, the main aim of this study is to determine the effectiveness of crumb tyre rubber mixed with soil samples as one of the soil stabilisation techniques and to establish the optimum usage percentage of crumb tyre rubber as a stabiliser. Clayey sand soil was mixed with 5%, 10% and 15% of crumb tyre rubber by weight of the soil sample and was tested for physical properties, such as particle size distribution and plasticity index. In obtaining the changes in strength, mixed clayey sand-crumb tyre rubber samples were subjected to compaction and California Bearing Ratio (CBR) tests. The results showed that the increment of crumb tyre rubber percentage as an additive, increased the CBR value and therefore enhanced the strength of the modified soil. However, the crumb tyre rubber stabiliser affected the optimum moisture content and maximum dry density of the modified samples by decreasing their values. The optimum percentage of crumb tyre rubber mixture was found to be 10% by weight at the end of this study. These findings indicate that the measured crumb tyre rubber is suitable for supporting the clayey sand soil for the subgrade of pavement construction. ABSTRAK: Pembinaan di atas tanah bermasalah yang mengandungi kapasiti galas rendah, kekuatan ricih rendah, kebolehmampatan tinggi dan kandungan air tinggi akan mengganggu kelancaran proses pembinaan dan akan menjejaskan kekangan masa dan wang akibat penyelenggaraan berulang. Jalan raya yang dibina di atas tanah yang bermasalah akan mengalami kegagalan turapan seperti keretakan, rekahan membujur dan pengepaman, disebabkan oleh subgrednya terdedah kepada pembengkakan atau pengecutan akibat perubahan kelembapan dan pemendapan berbeza. Oleh itu, penambah baikan tanah perlu dilakukan bagi mencapai kapasiti galas beban lebih baik untuk menampung beban di atasnya. Oleh itu, tujuan utama kajian ini adalah bagi menentukan keberkesanan serpihan tayar getah yang dicampur dengan sampel tanah sebagai salah satu teknik penstabilan tanah dan menentukan peratusan optimum penggunaan tayar getah sebagai penstabil. Tanah pasir liat sebagai bahan utama dalam kajian ini dicampur dengan 5%, 10% dan 15% serbuk tayar getah mengikut berat sampel tanah dan telah diuji sifat fizikalnya, seperti taburan saiz zarah dan indeks keplastikan. Perubahan dalam kekuatan ditentukan dengan cara menggaul sebatian sampel tayar getah bersama pasir tanah liat dan diuji dengan eksperimen pemadatan dan ujian Nisbah Bearing California (CBR). Dapatan kajian menunjukkan bahawa penambahan peratusan serbuk tayar getah sebagai bahan penstabil telah meningkatkan nilai CBR dan sekaligus meningkatkan kekuatan tanah yang diubah suai. Walau bagaimanapun, penstabil tayar getah mempengaruhi kandungan lembapan optimum dan ketumpatan kering maksimum sampel yang diubah suai dengan nilai berkurang. Pada akhir kajian ini, peratusan optimum bancuhan serbuk tayar getah yang diperolehi adalah sebanyak 10% berat sampel. Dapatan ini menunjukkan bahawa tayar getah remah adalah sesuai dalam menyokong tanah pasir liat bagi subgred pembinaan turapan.

Study on the Influence of a Rubber-Modified Soil Isolation Layer on the Isolation Performance of Frame Structures with Different Foundation Forms

“…At varying ultimate stress levels, the mixture incorporating rubber dust exhibited a strength that was 10-25% higher compared to the mixture containing rubber powder. Saparudin et al [5] incorporated 5%, 10%, and 15% of tire rubber fragments into the soil samples, and conducted tests to assess the physical properties of clay sand, including particle size distribution and plasticity index. The test results demonstrated that the tire rubber powder met the requirements for effectively stabilizing the clay sand soil in highway construction roadbeds.…”