Interlayer Strength of 3D-Printed Mortar Reinforced by Postinstalled Reinforcement.

This work was designed to evaluate the interlayer strength of 3D-printed mortar with postinstalled interlayer reinforcement. Two methods of postinstalled interlayer reinforcement were considered according to the amount of overlapping. The first method did not include overlapping of the interlayer reinforcement, while the second method included overlap lengths of 20 and 40 mm.

3D Internal Visualization of Concrete Structure Using Multifaceted Data for Ultrasonic Array Pulse-Echo Tomography.

This research proposes a 3D internal visualization using ultrasonic pulse-echo tomography technique to evaluate accurately the state of concrete structures for their efficient maintenance within a limited budget. Synthetic aperture focusing technique (SAFT) is used as a post-processing algorithm to manipulate the data measured by the ultrasonic pulse-echo technique. Multifaceted measurements improve the weakness of the existing ultrasonic pulse-echo tomography technique that cannot identify the area beyond a reflector as well as the area located far away from measuring surfaces.

Buildability and Mechanical Properties of 3D Printed Concrete.

Recently, 3D concrete printing has progressed rapidly in the construction industry. However, this technique still contains several factors that influence the buildability and mechanical properties of the printed concrete. Therefore, this study investigated the effects of the nozzle speed, the interlayer interval time, the rotations per minute (RPMs) of the screw in the 3D printing device, and the presence of lateral supports on the buildability of 3D concrete printing.

Corrosion Detection in PSC Bridge Tendons Using Kernel PCA Denoising of Measured MFL Signals.

The construction of prestressed concrete bridges has witnessed a steep increase for the past 50 years worldwide. The constructed bridges exposed to various environmental conditions deteriorate all along their service life. One such degradation is corrosion, which can cause significant damage if it occurs on the main structural components, such as prestressing tendons.

An Experimental Study on the Ductility and Flexural Toughness of Ultrahigh-Performance Concrete Beams Subjected to Bending.

Ultrahigh-performance concrete (UHPC) and high-strength concrete (HSC) are currently widely used because of their distinct superior properties. Thus, a comprehensive comparison of the flexural behavior of UHPC and HSC beams is presented in this study. Nine UHPC beams and three HSC beams were subjected to pure bending tests to investigate the effect of various reinforcement ratios and steel fiber volume contents on the cracking and failure patterns, load-deflection behavior, ductility, and flexural toughness of these beams.