Mechanical and radiation shielding properties of Philippine natural zeolite-mixed concrete

This study investigated the mechanical and radiation shielding properties of Philippine natural zeolite (PNZ)mixed concrete as a potential sustainable alternative to traditional cement in radiation shielding applications. Concrete mixtures with 0 %, 20 %, and 40 % PNZ replacement were tested for compressive strength, split tensile strength, and radiation shielding efficiency against X-ray and gamma radiation. The specific density of the control sample (pure concrete) is 1.75 g/cm(3) while the concrete with 20 % and 40 % cement replacements were 1.62 and 1.61 g/cm(3), respectively. Results showed that the 40 % PNZ mixture exhibited the highest mechanical strength, with a 400 % increase in the average compressive strength from the pure concrete mixture, attributed to the pozzolanic reaction between zeolite and calcium hydroxide. The 20 % PNZ mixture demonstrated the best radiation shielding performance, achieving the highest linear attenuation coefficients of 0.623, 0.433, 0.421, and 0.167 cm(-1) at 65, 100, 118, and 662 keV, respectively. As a result, the concrete with 20 % cement replacement also exhibited the highest mass attenuation coefficients at these energies. The total atomic cross-section followed the trend 0 % > 20 % > 40 %, with the control sample having the lowest mean free path (MFP) and half-value layer (HVL) at lower energies. Experimental and simulation results confirmed that the 20 % PNZ mixture offers an optimal balance between mechanical strength and radiation shielding while promoting sustainability by reducing cement usage.