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Pervious concrete is an effective and unique way to overcome critical environmental issues and support green, sustainable growth. Pervious concrete refers to a non-slip porous pavement concrete, which is permeable to water. Recently, the demand for sustainable waste palm oil products for construction in Malaysia has dramatically increased. For long-term sustainable development, palm products waste can be recycled in pervious concrete production. This study on pervious geopolymer concrete (hereafter PGC) explored an alternative binder and aggregate for Portland cement (OPC) and natural aggregate (NA), while it also developed a pervious concrete's compressive strength. Biomass aggregate (BA) was obtained by burning palm oil biomass. Thus, biomass aggregate (BA) is introduced as a replacement for natural aggregate (NA). In order to generate coated biomass aggregates (CBA), BA was combined with alkaline liquid (AL) and fly ash (FA) and then heated inside an oven at 80 degrees Celsius for 24 hours. PGC containing coated biomass aggregate is the most commonly used cement substitute in concrete as the industrial by-product waste. This study investigated the performance and optimised mixture design of various PGC mixtures that incorporated NA to replace BA CBA compared with OPC pervious concrete containing NA. PGC generated via CBA possessed greater compressive strength without any impact on permeability to water. Outcomes show that both CBA and BA are possible alternative aggregates for generating PGCs. As a result of this study, a nomograph chart was developed, which provided a guideline for designing PGC made by CBA and BA, and cement pervious concrete made with NA.

The influence of silica modulus (Ms) on the compressive strength of alkali activated ultrafine palm oil fuel ash based mortar has been investigated. Two alkali activated mortar mixtures, S1 and S2 were prepared using sodium silicate (Na2SiO3) with initial silica moduli, Ms of 3.3 and 2, respectively. The Na2SiO3 was used in combination with sodium hydroxide (NaOH) with NaOH concentration of 10 M. The results indicate that the S2 mortar mixture has higher strength than the S1 mortar mixture at all testing ages, with 28 day strength of 27.18 MPa and 32.8 MPa recorded by S1 and S2 mortar mixture, respectively. Hence, lower Ms leads to higher compressive strength. The higher compressive strength of S2 is corroborated by the formation of more C-S-H as implied by the Fourier Transform Infra-red (FTIR) spectra analysis.

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This study aimed to assesses the effect of various commercial Na2SiO3 on the compressive strength (CS) of alkaline activated fly ash mortar (AAFM). The three mixture of alkaline activated mortar (AAM) C1, C2 and C3 were prepared from the source material of fly ash and alkaline activator solution (AAS). The initial AAS was comprised of NaOH (10M) and various grade of Na2SiO3. The various grades of Na2SiO3 were characterized by their SiO2/Na2O molar ratio of 2.0, 2.2, and 3.3, respectively. The sample from each mixture was characterized based on the CS and microstructure changes using useful tools of XRD and FTIR analysis. The results obtained indicated that the highest CS achieved among the three mixtures were 48.23MPa of mixture C2 prepared with SiO2/Na2O molar ratio of 2.2. This was mainly due to higher binder formation (N-A-S-H gel type) and a higher rate of reaction of the main source material. This result is in line with XRD and FTIR analysis results finding.