Characterization of 3D Microstructure of Concrete Using Reconstructed Combined X- Ray and Neutron Tomography Image

X-ray tomography or neutron tomography are widely used as non-destructive methods that provide information on the internal microstructure of cement-based materials. Due to advancement of technologies, they are used to visualize concrete in 3D by stacking set of 2D images. Both methods are similar but provide different information: porosity of concrete or concrete durability. Using the combined X-ray and neutron tomography images, 2D images of the microstructure of concrete materials are obtained and can be reconstructed into 3D. The objectives of this study are to visualize the 3D reconstruction from the 2D images and characterize concrete microstructure using combined X-Ray and neutron tomography images already reconstructed into 3D. One also compares the reconstructed microstructure obtained with each imaging technics separately. The threshold value of each phases are already provided and directly used to segment voids and aggregates. The study on the reconstructed microstructure using a single tomogram (X-ray or neutron CT) has shown limitations for concrete that contains polymineral aggregates. However, the microstructure characterization based on the complementary image shows an accurate results similar to the mixing design of concrete. Finally, the 3D reconstruction successfully shows a realistic representation of the internal structure of concrete, which is often difficult to obtain.