A mortar composition, which includes (i) a treated palm oil fuel ash, wherein the treated palm oil fuel ash is the only binder present, (ii) a fine aggregate, (iii) an alkali activator containing an aqueous solution of sodium hydroxide and sodium silicate, and (iv) aluminum hydroxide as a strength enhancer. A cured mortar made from the mortar composition is also disclosed with advantageous compressive strength properties.

A mortar composition, which includes (i) a treated palm oil fuel ash, wherein the treated palm oil fuel ash is the only binder present, (ii) a fine aggregate, (iii) an alkali activator containing an aqueous solution of sodium hydroxide and sodium silicate, and (iv) aluminum hydroxide as a strength enhancer. A cured mortar made from the mortar composition is also disclosed with advantageous compressive strength properties.

A mortar composition, which includes (i) a treated palm oil fuel ash, wherein the treated palm oil fuel ash is the only binder present, (ii) a fine aggregate, (iii) an alkali activator containing an aqueous solution of sodium hydroxide and sodium silicate, and (iv) aluminum hydroxide as a strength enhancer. A cured mortar made from the mortar composition is also disclosed with advantageous compressive strength properties.

Compositions and methods of forming compositions for a controlled low strength material (CLSM) comprising heavy oil fuel ash (HOFA) and recycled concrete powder (RCP) waste with natural and recycled aggregates and water are provided. In some embodiments, small quantities of Portland cement are also utilized. The recycled concrete powder contains primarily calcite and quartz. The CLSM can be used as a flowable compacted fill in structural and non-structural construction applications.

A controlled low strength material has constituents that include a cement, an aggregate, and a water. The aggregate includes concrete demolition waste. The controlled low strength material has a compressive strength that does not exceed 8.3 MPa, measured at 28 days. The controlled low strength material can alternately include a heavy oil fuel ash and the controlled low strength material can have a compressive strength that does not exceed 2.10 MPa, measured at 28 days.

A controlled low strength material has constituents that include a cement, an aggregate, and a water. The aggregate includes concrete demolition waste. The controlled low strength material has a compressive strength that does not exceed 8.3 MPa, measured at 28 days. The controlled low strength material can alternately include a heavy oil fuel ash and the controlled low strength material can have a compressive strength that does not exceed 2.10 MPa, measured at 28 days.

A foam concrete has constituents that include a cement, a sand, a coarse aggregate, an oil ash, a water, and a foam solution. The foam concrete has a compressive strength of at least 20 MPa, a thermal conductivity of less than 0.41 W/mK and a maximum weight of 1650 kg/m.sup.3.

A foam concrete has constituents that include a cement, a sand, a coarse aggregate, an oil ash, a water, and a foam solution. The foam concrete has a compressive strength of at least 20 MPa, a thermal conductivity of less than 0.41 W/mK and a maximum weight of 1650 kg/m.sup.3.

A mortar composition, which includes (i) a treated palm oil fuel ash, wherein the treated palm oil fuel ash is the only binder present, (ii) a fine aggregate, (iii) an alkali activator containing an aqueous solution of sodium hydroxide and sodium silicate, and (iv) aluminum hydroxide as a strength enhancer. A cured mortar made from the mortar composition is also disclosed with advantageous compressive strength properties.

A mortar composition, which includes (i) a treated palm oil fuel ash, wherein the treated palm oil fuel ash is the only binder present, (ii) a fine aggregate, (iii) an alkali activator containing an aqueous solution of sodium hydroxide and sodium silicate, and (iv) aluminum hydroxide as a strength enhancer. A cured mortar made from the mortar composition is also disclosed with advantageous compressive strength properties.