Since the 1964 Niigata and Alaskan earthquakes, which incurred severe liquefaction damage, liquefaction-related design for infrastructures and buildings has been developed exclusively on the principle of force equilibrium. However, the energy concept is increasingly recognized as superior for simplified and robust liquefaction designs because of the uniqueness of energy capacity in soil failures regardless of the differences in earthquake loads. The energy-based liquefaction evaluation method (EBM) has been pursued by many investigators where dissipated energy for liquefaction is focused in place of liquefaction strength defined in the conventional stress-based method (SBM). Furthermore, the EBM enables sound liquefaction-related designs without resorting to sophisticated but highly variable/tricky numerical analyses and contributes as a scale to measure the reliability of those numerical tools. Thus, the EBM, though short of practical use in today's engineering works, should be able to serve as a simplified liquefaction evaluation tool besides the SBM. We reviewed the basic idea as well as the recent developments of the EBM together with the supporting data. We also discussed how to simplify and approximate the energy-based liquefaction behavior to implement robust evaluations in practical problems. The EBM liquefaction evaluation steps were delineated and exemplified by case studies for practicing engineers compared to the SBM.

Safe and efficient conservation of cultural artifacts requires preventing artifacts deterioration and energy-saving environmental control. To achieve this, predicting deterioration caused by environmental conditions is necessary. Predicting the mechanical damage caused by humidity fluctuations necessitates knowledge of the mechanical properties of cultural artifacts materials. Although the mechanical properties of several artifacts have been extensively studied, no investigations have focused on the soils underlying wall paintings. This study aims to clarify some mechanical properties of the upper- and middle-coat soils serving as the substrates for Hiten wall paintings at Horyu-ji Temple. Mock-up materials were prepared, and splitting tensile and uniaxial compressive tests were performed. Simultaneously, specimens with various equilibrium humidities were tested to clarify their humidity dependency. The tensile and compressive strengths, Young's modulus, proportional limit, and Poisson's ratio of the upper-coat soil were 0.103-0.239 MPa, 1.16-2.55 MPa, 0.115-0.209 GPa, and 1.10-2.49 MPa, and 0.152, respectively. Moreover, the humidity-induced strains for the upper- and middle-coat soils were measured, and the moisture expansion coefficients were approximately 1240 and 2337 mu ST/-, respectively. The results of this study provide vital data for the conservation of the wall paintings and contribute to a deeper understanding of wall soil properties.