Effect of curing time on selected properties of soil stabilized with fly ash, marble dust and waste sand for road sub-base materials

Abstract

The properties of sub-base filling materials in highway construction are essential, as they can determine the performance of the road in service. Normally, the existing materials are removed and replaced with new materials that have adequate load-bearing capacity. Rising environmental concern and new environmental legislations have made construction professionals consider other methods. These methods include stabilizing the existing materials with other additives to improve their performance. Additives can be waste materials generated by different industries. In this work, the existing excavated soil is stabilized with waste materials. The wastes consisted of fly ash, marble dust and waste sand. The percentage addition of waste materials was 5%, 10%, 15% and 20% (by mass) of the existing soil. The soil/waste specimens were cured for 1, 7, 28, 56, 90 and 112 days before testing. Testing included the dry unit weight and unconfined compressive strength ( q) as well as X-ray diffraction analysis and scanning electron microscopy observation. Also, the California Bearing Ratio values were obtained and are reported in this investigation. The results showed that the q values increased with the increase in waste materials content. Also, there is tendency for the dry unit weight to increase with the increase in waste materials.

Strength, Hydraulic, and Microstructural Characteristics of Expansive Soils Incorporating Marble Dust and Rice Husk Ash

“…Similarly, the decrease in MDD is significant for 1% to 9% addition of both lime and cement than 2% to 12% blending with MD and RHA separately, with MD marking the least reduction of all. However, reference [37] concluded that MDD of medium plasticity clay is expected to increase with the addition of fly ash, MD, and "waste sand"; the results obtained in the present study are somewhat deviating because of two main aspects. Firstly, for the RHA-clay blends, the compaction curves move diagonally downward to the right with an increase in RHA content, which leads to a decrease in MDD and an increase in the OMC.…”

“…Figure 3 suggests that cumulative passing percentage at equivalent grain size diameter of 0.002 mm is 45% and 40% for MD and RHA, respectively. e curing duration of 112 days was selected to study the long-term curing effect on strength characteristics of stabilized soils [37]. Upon completion of every curing period, the specimens were tested according to nomenclature presented in Table 3.…”

“…MD sludge is produced in large quantity, which is openly landfilled, thus leading to environmental damage and health risks. Positive results have been achieved in the construction industry when it was incorporated in soil, bricks, production of cement, concrete, and so on [36][37][38]. After performing a multitude of consolidated undrained triaxial compression on recycled tire treated-cement treated samples at 7, 14, and 28 days of curing, it was found that the undrained shear strength parameters improved significantly due to the formation of cementation compounds [39].…”

“…Demolished tile material improved the plasticity index and pH of soft soil, and its addition lowered down the water holding capacity, while the maximum dry density was recorded to be increased by almost 10% [40]. Furthermore, Firat et al [37] used marble dust in soil stabilization for road construction where the medium to low plasticity soil was used as road base filling material. e tests results on the samples treated with up to 15% marble content and cured for 112 days indicated an increased amount of Tobermorite, thereby increasing the compression strength.…”

The usability of industrial wastes on soil stabilization

“…The formation of cementitious material by the reaction of lime with the pozzolans (Al 2 O 3 , SiO2, Fe 2 O 3 ) the presence of water is known as the hydration of FA. The hydrated calcium silicate gel or calcium aluminate gel can bind material together (Fırat et al, 2017). In the soil sample, no texture of the bond is seen (Figure 5e, f).…”