The Effect of POFA-Gypsum Binary Mixture Replacement on the Performance of Mechanical and Microstructural Properties Enhancements of Clays

Abstract

Soft clay is categorized as problematic due to its weak and dispersive properties which requires stabilization. In Malaysia, there is another challenge, the increment of palm oil waste productions to meet the global demand for food oil. These two concerns motivate engineers to develop novel strategies for exploiting palm oil waste in soil stabilization. Utilizing POFA as a soil stabilizing agent is an economical and sustainable option due to that POFA contains high pozzolanic characteristics which make it more suitable and reliable to treat soft soil. This study uses the replacement portion of the soil with stabilizing agents -POFA and Gypsum; aiming to achieve Malaysia green technology goals by the balance of the economic expansion and environmental privilege. However, the aim of this study is to determine the effect of POFA-gypsum binary mixture replacement on the performance of mechanical and microstructural properties en-hancements of clays. Kaolin S300 is the control sample whereas POFA and gypsum are the used binders. The mechanical properties and shear strength with the curing period were tested. Results showed that treated clay marked increment of optimum water contents and reduction of maximum dry densities, a clear 200% of enhancement of treated clay’s compressive and shear strength with curing period as well as the amount of stabilizing agent to less than 15% of POFA and 6% of POFA. It is also found that as gypsum contains a high amount of lime (CaO), the results illustrate that strength raises significantly even with less curing time due to its high reactivity compared to silica and alu-mina. Overall, the results show an enhancement of mechanical and shear strength properties of treated kaolin supported by microstructural SEM imaging.

Development of Clay-Composite Plasters Integrating Industrial Waste

“…In clay composites, NaCl was introduced as an 8% saline solution prepared by dissolving the salt in potable water. -Hydraulic lime was chosen based on initial experimental tests and numerous literature findings that highlight its positive impact in reducing drying shrinkage and the likelihood of fissuring, due to the added calcium oxide content [62][63][64][65][66][67][68][69][70][71]. In this instance, preliminary experimental research examined the effects of partially substituting clay with hydraulic lime in compositions consisting of clay, fly ash, and limestone sludge.…”

Structural Formation of Soil Concretes Based on Loam and Fly Ash, Modified with a Stabilizing Polymer Additive

“…In this case, structure formation, in comparison with soils treated with cement, proceeds slowly, and the strength characteristics of the samples are studied after 90–360 days of hardening. A qualitative difference is revealed in the processes of interaction with various binders and additives due to the large specific surface area of the dispersed parts of the waste [ 56 , 57 ]. When a stabilizer and a binder are introduced into the clay soil, physicochemical and colloidal processes take place, which make it possible to impart specified properties to road building composites [ 58 , 59 , 60 ].…”

Recyclable Materials for Ecofriendly Technology

“…These results are an excellent summary of many years of research by these authors [ 38 , 39 , 40 , 41 ]. Alhokabi et al [ 42 ] used the replacement portion of the soil with stabilizing agents such as palm oil fuel ash and gypsum. A team led by Niemiec [ 43 , 44 ] evaluated the efficiency of the conversion of biomass contained in the whitewater fraction of municipal waste and sewage sludge using methanogenesis.…”