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This paper focuses on the ultimate state of three‐story wood dwellings with high aspect ratios, which are increasing in Japan's urban areas. Using shaking table test results from the 2019 full‐scale shaking table test, a comprehensive study is conducted on the accuracy of evaluating ultimate state through the story shear failure mode at the first story, the tension fracture mode at the wall base of the first story, and foundation sliding mode on the soil. Methods evaluating the dynamic response behaviors of the building systems are also investigated. In the test, the current Japanese seismic design guidelines were applied, and two Grade‐3 buildings were prepared. One adopted the Post‐and‐Beam structure (A‐building), and the other the Shear‐Wall structure (B‐building). A series of tests planned very different physical boundary conditions surrounding their reinforced concrete (RC) mat foundations. The sills, column bases and wall bases of the upper wood structures were anchored to the RC foundations by steel anchor bolts, according to the current Allowable Stress Design (ASD) requirements. In the first stage, A‐building equipped a Base‐Isolation system, while B‐building represented a generic foundation constructed on a 1.5 m‐height real soil ground by preparing a rigid soil box (Foundation‐Soil system). In the second stage of A‐building and B‐building, the foundation was firmly fixed (Fixed‐Foundation system), and shaking table motions were fully applied to the foundations. The entire test system was setup on the large shaking table facility at E‐Defense, and a series of tests were conducted using JMA‐Kobe motion and JR‐Takatori motion recorded in the 1995 Kobe earthquake as Maximum‐Considered‐Earthquake motions. Confirmed was the change in the structural mechanism due to the upper structural systems and the foundation boundaries. Regarding the upper wood structure performance in the Fixed‐Foundation system, a story shear failure mode was observed at the first story in A‐building, while a tension fracture mode at the base of the first story in B‐building. This difference of failure mode is difficult to determine with ASD. The maximum strength were more than four times higher than the ASD base shear force. Tension fracture capacity at the wall base was mainly enhanced by the presence of the steel anchor bolts. Regarding the foundation performance in Foundation‐Soil system of B‐building, a horizontal displacement up to 240 mm was observed between the foundation and soil when JMA‐Kobe 100% was applied. A response reduction effect was observed in the upper wood structure, similar to the Base‐Isolation system of A‐building. The initial friction and cyclic friction strength capacities between the foundation and soil were quantitatively evaluated considering the horizontal two‐directional sliding. The representative test results were converted to the corresponding SDOF systems based on the first mode response assessment. In the Fixed‐Foundation system, the dynamic response characteristics of the upper wood structures were properly represented using Ibarra‐Medina‐Krawinkler pinching model in the equivalent SDOF system. [ABSTRACT FROM AUTHOR]

The relevance. The waste of Baikal Pulp and Paper Mill causes a real danger of a social and environmental disaster for Lake Baikal and the entire Southern Baikal region, therefore, the problem of developing integrated solutions for dumping the accumulation of lignin-containing waste is especially acute. One of the promising areas for processing this type of waste is the use of natural processes, for example, freezing in winter, temperature detection or self-overgrowth of the occurrence of natural succession. The main aim of the research is to develop an environmentally friendly technology for processing colloidal lignin-containing waste from the pulp and paper industry. Methods: pilot tests at the Solzan industrial site of Baikal Pulp and Paper Mill for freezing lignin-containing wastes and obtaining soils from them by mixing with additives; performing quantitative chemical analysis using the methods of atomic absorption and atomic emission spectrometry, high performance liquid chromatography, toxicological analysis. Results. Pilot tests have shown that after freezing, the colloidal structure of lignin-containing sediments is destroyed with a decrease in volume up to 40 %, humidity up to 60 %, and also with a decrease in toxicity – from the third (moderately hazardous) to the fourth (low hazardous) and fifth class (practically non-hazardous) of hazard of the waste depending on its composition. After freezing, the resulting sludge with the introduction of various additives (CHP ash, sewage treatment plant sludge) can be used as soil ground and fertilizers for reclamation of disturbed lands and crops. Thus, an environmentally friendly technology was developed for processing waste from the pulp and paper industry to obtain soil ground, which is low-energy and does not contain expensive imported equipment.

The paper presents an efficient numerical technique for 3D-modeling of seismic stability of large buried structures. This technique allows considering the subsoil-structure contact interaction, gravity field effects, the inhomogeneous structure of soil and the varieties location of the earthquake hypocenter. As part of this technique is substantiated sizing of the soil-structure computational domain and continuum model for hard and soft soil foundations describing. The numerical technique for determining the kinematic conditions at the lower boundary of the computational domain from the experimental accelerations at the soil surface is given, offered special non-reflecting waves boundary conditions. The methods described above and algorithms for seismic resistance solving have been implemented in certified software package "Dynamica-3", parallelization of the algorithm has been held according to the spatial domain decomposition principle. The developed numerical technique allows correctly posing the problem of seismic vibrations of buried structure, reducing computing costs and increasing the efficiency of numerical studies of Earthquake Engineering. Through this, the multiple recalculation of the task with different action scenarios generated from experimental seismograms by probabilistic methods became technically possible. The results of these calculations allow reflecting the experience of many earthquakes, which increases reliability of the estimates. The paper presents the model calculations results of seismic stability of large-sized buried structure—the mutual vertical and horizontal displacement of soil and building walls—which can then be used to assess strength of adjacent underground pipelines. A number of numerical experiments on seismic vibrations of nearby large-sized structures have been carried out to assess the mutual influence of structures on their behavior in an earthquake. It is established that the influence of nearby large-sized objects on seismic vibrations of structures differs for different buildings. [ABSTRACT FROM AUTHOR]