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Within the domain of municipal solid waste (MSW) management, incineration is recognized as an efficient volume reduction method, yet it produces substantial quantities of bottom ash (IBA). Redirecting IBA into cementitious frameworks is challenging due to diminished workability, mechanical properties, and durability. This study investigates alumina micro powder (ALMP)'s effect on improving the mechanical and durability aspects of ecological ultra-high performance concrete (EUHPC) produced with IBA. The research examines ALMP's role at various doping levels on the EUHPC's rheological properties, mechanical strengths, durability indices, ultrasonic pulse velocity (UPV), and elastic modulus. Additionally, nanoindentation tests discern ALMP's reinforcing effect on EUHPC's stiffness. Summarizing key findings: ALMP significantly enhances EUHPC's flexural and compressive strengths, with increases ranging from 6.98 % to 24.87 % and 12.39–20.81 %, respectively. Moreover, ALMP raises the elastic modulus by 6.05–19.07% and UPV by 3.11–7.18 %, reflecting a denser, more compact matrix structure. Durability enhancements are evidenced by reductions in drying shrinkage by 4.41–20.01 % and decreased chloride migration by 7.01–22.14 %. Nanoindentation reveals a densification in the microstructure, with escalated high-density C-S-H phases and reduced low-density C-S-H and unhydrated materials. IBA replacement yields energy savings of 11.43 %, CO 2 emission reduction of 7.01 %, and cost savings of 1.18 %. The optimal ALMP inclusion is identified at 10 %, balancing workability, mechanical and microstructural benefits in EUHPC. These revelations position IBA as a useful component in the concrete sector and advocate for ALMP as a beneficial adjunct to elevate the performance of IBA-based concrete towards sustainable development goals. • Mixture of eco-UHPC was designed via MAA particle packing model. • Properties of eco-UHPC were improved via Al 2 O 3 micro-powder. • Optimal content of Al 2 O 3 micro-powder in eco-UHPC was 10%. • Al 2 O 3 micro-powder contributed to a denser microstructure of eco-UHPC. • Environmental friendliness of eco-UHPC was improved via Al 2 O 3 micro-powder. [ABSTRACT FROM AUTHOR]

• SCM with high elastic modulus was developed by using AMP. • Fluidity, microstructure, mechanical strength, and durability of SCM were studied. • DME of SCM was characterized via ultrasonic testing technology. • DME of SCM was increased by 4.37 ∼ 9.97% due to the addition of AMP. • Durability properties of SCM were markedly improved due to the addition of AMP. Cementitious composites are one of the most widely used building materials in civil engineering. However, their low Young's modulus cannot meet the requirements of long-span structures. This work carried out a feasibility study on producing self-compacting mortar (SCM) with high elastic modulus by using Al 2 O 3 micro powder (AMP). Effects of AMP on the workability, microstructure, mechanical properties, and durability properties of SCM were systematically investigated. The dynamic modulus of elasticity (DME) of SCM was characterized via ultrasonic testing technology. It was found that, 1) due to the addition of AMP, the porosity of SCM was reduced by 2.64 ∼ 13.64%, and the threshold pore diameter of SCM was decreased; 2) the flexural strength and compressive strength of SCM were increased by 4.40 ∼ 15.85% and 2.35 ∼ 14.33%, respectively, because of the incorporation of AMP; 3) the drying shrinkage of SCM was reduced by 6.46 ∼ 11.21%, and the chloride migration coefficient of SCM was decreased by 3.38 ∼ 18.64%, due to the addition of AMP; 4) the optimal content of AMP in SCM was 10%, considering the effects of AMP on the microstructure, mechanical properties, and durability properties of SCM; 5) it was feasible to produce SCM with high elastic modulus by using AMP, and the DME of SCM was increased by 4.37 ∼ 9.97%, because of the incorporation of AMP. [ABSTRACT FROM AUTHOR]