Stabilisation of soft soil with recycled plaster admixtures

Abstract

Solid waste management is a serious problem worldwide as the amounts of produced wastes are increasing annually. For example, the disposal of waste gypsum plasterboard, used as dry walling across the world, represents a serious environmental issue. Therefore, this study examines the potential for reusing plasterboard wastes as a stabiliser material for earthwork projects, especially for organic soft clay soil. Recycled plaster, mixed with cement or lime at different ratios was used as a stabiliser for tested soil. Atterberg limits, scanning electron microscopy, x-ray diffraction, compressive strength, and secant moduli tests were conducted to evaluate the improvement in stabilised soil properties. The results indicate that the inclusion of plaster–cement (B–C) or plaster–lime (B–L) admixtures improved the geomechanical properties of the stabilised soil, with higher admixture concentrations leading to greater improvement. Moreover, the soil specimens stabilised using the B–L admixture exhibited a higher strength gain rate and reduction in plasticity index and water content than those stabilised by the B–C admixture. The development of cementation compounds in a stabilised soil matrix has a considerable effect on permanent strength enhancement. It is concluded that the proposed stabilising technique can be valuable for both waste management and construction industries.

Compactability of Agro based Geopolymer using Sodium Silicate Activator

“…While OMCvalues decrease as RHA content increases for both soilsamples. These aredue to coating and replacement of soil bythe additives contents in the mixture, which resulted in largeparticles with larger voids and density.The addition of Cement and RHA contents also decreased thequality of free silt, clay fraction and coarse materials withlarge surface areas formed Chang and Cho (2019) and Alhmed et al (2018). The increase in MDD, CBR and consequent decrease in OMCvalues is also due to gradual formation of cementitiouscompound between the additives and Calcium Hydroxide(Ca(OH)2) present in the soil, thus increase in coarse particlesof the soil through cementation.…”

Influence of the Heating Temperature and Fineness on the Hydration and Mechanical Property of Recycled Gypsum Plaster

“…Increasing amount of waste gypsum and the lack of gypsum resources have become a worldwide problem, which has attracted more and more attention [1,2]. Research studies to solve the problem of waste gypsum have begun, and new methods for the treatment of waste gypsum in many fields have been proposed, such as preparation of cement [1,3], soft clay improvement [4,5], and so on. Among these solutions, the use of waste gypsum as recycled gypsum plaster seemed to be a sustainable solution, and it was also considered a positive step towards circular development in the construction industry [6].…”

Editorial

“…Ahmed et al (2018) investigate the use of waste gypsum plasterboard as a stabiliser material for organic soft clay soil. Their results confirm that the introduction of recycled plaster with cement can improve the strength and stiffness of the treated soil.…”