Investigation on Particle Contact Angle of Fresh Concrete Using X-ray CT Imaging
Zhuguo LI, Kentaro KAJIWARA and Minoru IIDAKA
Abstract: It is important to clarify the variation of particle contact angle of fresh concrete with shear deformation for understanding its deformation resistance and mechanical behaviors. In this study, using X-ray imaging and Computed Tomography, the authors investigated mean particle contact angles (Į) of fresh mortar before and after sheared in a ring shear device, which was composed of alumina powder, sand, and water, etc. As a result, the mean particle contact angle increases with increasing the shear deformation, but when reaching a peak, it decreases with the shear deformation. The increase and the decrease of Į are respectively the characteristics before and in shear failure state. Also, the greater the vertical stress on the shear plane, the smaller the increase or decrease of Į with the shear deformation. Key Words:Fresh concrete, Particle contact angle, Shear deformation, Vertical stress, X-ray CT imaging, Synchrotron radiation