The Japanese Society for Non-Destructive Inspection established and has been revising the Standard of the Japanese Society for Non-Destructive Inspection（NDIS） in cooperation with related organizations, and promotes the standardization of inspection technology and its diffusion. This paper gives an overview of NDIS 3418-2022 “Method for visual testing of concrete structures” as revised in September 2022. The aim of this revision is to create a standard for visual testing of concrete structures that can be cited（referenced） by relevant parties. Specifically, for the sake of consistency with NDIS 3414（Method of visual testing）, the structure of the NDIS 3418 standard was revised, limiting the scope of the standard to common items that are characteristic of visual testing of concrete structures.

High-strength concrete is widely used, mainly in high-rise reinforced concrete buildings. However, the low water-binder ratio and high powder content of high-strength concrete results in high viscosity, which has long raised issues related to workability, such as pumpability, placeability, compactability, and finishability. In response, a questionnaire survey was conducted on the construction workability issues related to the properties of fresh concrete and the unit water content of high-strength concrete. The results revealed that there are still finishability and pumpability issues, and that most contractors believe that the properties of fresh concrete should be improved by increasing the unit water content up to 185 kg/m³.

This technical report discusses a method to evaluate the member stiffness of steel beams with reinforced concrete encased ends with boundary steel plates between the steel region and the reinforced concrete regions. The primary objective of this study is to examine and clarify the properties of the evaluation model constructed to capture the experimental values of this type of beam from the elastic region to the inelastic region by verifying the validity of the solution it provides, based on the premise of the application of this evaluation model to the current structural design system in the domestic architectural sector. The secondary objective of this study is to present examples of issues that can be anticipated in design practice for steel beams with reinforced concrete encased ends in general, to discuss the possibility of using this evaluation model and its properties to address these issues, and to attempt to offer knowledge that will contribute to further refinement of the design of this type of structure.

Roughening by chipping is frequently employed for joint planes of concrete, such as joint planes of seismic retrofitting using steel braces and strengthening shear walls. The authors have developed a cylindrical shear key that can be formed in a uniform shape as an alternative to roughening by chipping, with consideration to the construction environment. The use of wet core drills for the production of cylindrical shear keys has the advantage of suppressing noise, vibration, and dust. Furthermore, it makes it possible to evaluate shear strength and facilitates post-construction management. This paper reports on environmental measurements taken at an application site of cylindrical shear keys, the construction method, shear strength evaluation, and the application of the proposed method to seismic retrofitting with strengthening shear walls.