Experimental Analyses and Numerical Models of CLT Shear Walls under Cyclic Loading

This paper reports the results of an experimental campaign performed at the University of Tokyo on cross-laminated timber (CLT) panels subjected to lateral loads. Analytical and numerical interpretations are provided as well, comparing the experimental analysis results with two methods: firstly, an analytical method to preliminarily evaluate the ultimate strength of the four panels, based on the geometrical dimensions of the openings and of the panel; secondly, a finite element model has been developed in order to provide some guidelines for calculating the stiffness and elastic behaviour of CLT panels subjected to lateral loads. The experimental tests showed that the CLT panels are as more brittle and stiffer as more the difference between the total panel area and the fenestrated area is high. The presence of large openings determined stress concentration at the corners where failure occurred for the attainment of the maximum tension strength in the inner layer. The proposed analytical formulation was shown to fairly closely predict the ultimate strength of panels with same geometry, characteristics and boundary condition, allowing preliminary information of this relevant parameter

A Study on the Construction History of Kintai Bridge in Japan

The aim of this research is to present a structured and comprehensive history of the rebuilding process of the Kintai Bridge and also to analyze the building knowhow of this particular structure that has been passed down to generations of carpenters. A great part of the information was obtained from interviews with the carpenters that worked on the most recent rebuilding process and also on available historical materials, such as drawings and tools that were used in past rebuildings. This research analyzes the history of the bridge by dividing it into three distinguished periods. In the first period, the bridge is considered to have maintained its original design and as such; in the Heisei Era rebuild, carpenters decided to restore the Kintai Bridge to this original form using the earliest available drawings from the Genroku Era. During the second period, carpenters developed their own design templates and measuring units in the form of rulers to guide the rebuilding process. The last and third period covers the modernization of the bridge since the Showa Era rebuild (1950)

A digital twin prototype to visualize heterogeneous seismic damage simulation results on web-GIS

Access to a wide range of information tailored to specific purposes, including extensive damage projections and statistics for target areas and the potential for individual building and dwelling damage predicted through simulations, enhances cities’ resilience against large-scale earthquakes. Recognizing the significance of this, we have developed a prototype of a digital twin capable of comprehensively visualizing various simulations on a web-based geographic information system (GIS) platform. This prototype employs three seismic damage simulators: the Integrated Earthquake Simulation for area damage, the wallstat for wooden houses, and the E-Simulator for a reinforced concrete building. A trial of earthquake damage simulations was conducted to assess this prototype’s efficacy, focusing on the damage incurred in Mashiki Town during the 2016 Kumamoto earthquake. The trial successfully verified the capability of the system to visualize and integrate various types of simulation data alongside records obtained from actual earthquake disasters. This paper provides an overview of the digital twin prototype. It reports on the trial’s results, focusing on the visualization and integration achieved through this trial

Local response to light excitation in the charge-ordered phase of (EDO-TTF)2Sb F6

The family of materials (EDO-TTF)2XF6 represents quasi-one-dimensional quarter filled systems exhibiting insulator-to-metal (I-M) phase transition at thermal equilibrium. (EDO-TTF)2PF6 is known to undergo a photoinduced I-M conversion with cooperative response to light excitation. Here we use femtosecond pump-probe experiments to study the photoresponse of (EDO-TTF)2SbF6 made of a larger counteranion SbF6 compared to the well studied (EDO-TTF)2PF6. In the early stage of the photoinduced process, we reveal a multicomponent coherent oscillating feature. The evolution of this feature with excitation density and temperature points to the local nature of the photoswitching in (EDO-TTF)2SbF6. At longer time scale, we did not detect the features associated with the transformation to the M phase, albeit observed in the PF6 derivative. We propose a scenario whereby the bigger size of the counteranion in (EDO-TTF)2SbF6 hinders the establishment of this transformation at macroscopic scale