Wooden framing structures are commonly used in construction due to their sustainability and versatility. However, their structural performance under various loading and environmental conditions still ...needs to be investigated. This study focuses on numerically modelling the behaviour state of a wooden framing system that has been reinforced with local stiffening elements. In order to improve the overall structural integrity and load carrying capacity of the framing system, local stiffeners are strategically placed at critical points. To do this, finite element analysis (FEA) techniques are used to simulate the behaviour within the frame assembly. The study starts by determining the material properties and geometrical characteristics of the wooden framing and stiffening elements. Boundary conditions, loading scenarios and constraints are defined to simulate real world conditions. The FEA results are then analyzed to evaluate the effect of local stiffening elements on own oscillations, deformation distribution and overall structural performance. The research findings are expected to offer valuable insights into the optimization of wooden framing systems, resulting in improved structural reliability and load-carrying capacity.
Theoretical and experimental methods for obtaining and investigating effective thermomechanical characteristics - residual stresses and deformation in panels made of nanomodified materials with ...asymmetrical reinforcement scheme have been developed in this paper. The study of the residual stress-strain state of structural elements made of carbon plastic using the values of thermoelastic characteristics of composite monolayers identified on the basis of the developed methods meade it possible to reveal the possibility of reducing the residual stress-strain state in structures with asymmetric reinforcement schemes.
Актуальность. В статье рассматривается проблема строительства и эксплуатации трубопроводов на участках распространения пучинистых грунтов. Рассматриваемая проблема является актуальной, поскольку ...одной из основных причин, осложняющих процесс прокладки трубопроводных систем в северных районах, является морозное пучение, заключающееся в многократном увеличении объема влажных грунтов при замерзании. Металл труб подземных магистральных трубопроводов при их эксплуатации на участках распространения пучинистых грунтов подвергается существенным деформациям, происходящим из-за неконтролируемых подвижек грунта вследствие процесса морозного пучения. Данное силовое взаимодействие подземного трубопровода и мерзлого грунта может стать причиной возникновения аварийных ситуаций. Цель: создать 3D-модель взаимодействия трубопровода с мерзлым пучинистым грунтом для того, чтобы имитировать процесс пучения грунта и выявить графическую зависимость напряжений и деформаций, возникающих в трубопроводе, от перемещения грунта. Объекты: участок трубопровода, проложенный на участках распространения пучинистых грунтов. Методы. В процессе исследования была изучена литература и нормативные документы по строительству и эксплуатации сооружений в многолетнемерзлых грунтах и проведен анализ влияния пучинистых грунтов на здания и сооружения, а также проведено моделирование в программном комплексе Ansys. В работе анализируется процесс взаимодействия многолетнемерзлых грунтов с подземным трубопроводом в программном комплексе AnsysWorkbench. Результаты. Авторами выполнено моделирование процесса пучения грунта и проведена оценка напряженно-деформированного состояния трубопровода, проложенного на участках распространения пучинистых грунтов, в программном комплексе AnsysWorkbench. С помощью разработанной модели получены и проанализированы значения напряжений и полных деформаций стенки трубы при контакте с мёрзлым грунтом, построена графическая зависимость наблюдаемых величин при усилении процесса пучения и увеличении участка пучения.
The technogenic impact of mining on the environment is analyzed and the transition to geotechnology with stowing to reduce the impact of mining operations is proposed. The results of the research ...work devoted to the justification of parameters of the development of salt deposits with stowing and the definition of the influence of stowing on the dynamics of deformation of the underworked rock massif are presented. The relevance of research aimed at creating a safe and efficient technology for the transition from systems with natural maintenance of stoping space to systems with stowing has been substantiated. The results of studies on qualitative and quantitative assessment of the state of the rock massif (by the finite element method using FLAC3D software), worked out by combines, are given and the dynamics of the impact of mining operations on the rock mass and the change in the maximum stresses during the hardening of the stowing in the chambers are revealed. The numerical modeling method is used to analyze the conditions of change in the state of the underworked rock mass, to establish the mechanisms of its deformation at various stages of development. It is recommended to use this approach for geotechnical assessment of the rock mass state in conditions of using development systems of different classes.
The stress-strain state of ZrB2-SiC ultra-high-temperature ceramics, produced using commercial powders with different impurity levels, was investigated by X-ray diffraction. Upon analysis of ZrB2 and ...SiC diffraction lines shift, the level of thermal stresses (strains) of the different phases was determined. An increase of internal stresses in ceramics with rising viscous-brittle transition temperatures, Tve, was attributed to increased grain boundary strength. Ceramics, for which high Tve and high level of internal stresses were estimated, exhibited high strength, up to 700 MPa at 1400 °C. A field of compressive thermal stresses in the matrix phase resulted to be necessary for achieving high strength at low-temperatures. On the contrary, the presence of low-melting impurities at the grain boundaries negatively impacted on the stress level in ZrB2 boundaries in the high temperature regime.
Currently, the improvement of methods for calculating building structures is continuing, including, among other things, methods for determining the magnitude of the load. Despite the fact that for ...most impacts, the principles of determining loads and methods from the application have been formed for a long time, a number of special tasks are sometimes encountered in design practice, for example, the impact of tsunami waves on a structure. This article is devoted to modeling the wave roll on a structure in the "Fluid Flow (Fluent)" module of the ANSYS 2021 software package and comparing the results obtained with the methodology presented in SP 292.1325800.2017 "Buildings and structures in tsunami-prone areas. Design rules". The studies presented in this article have shown that the nature of the propagation of hydrodynamic pressure when modeling wave rolling in ANSYS is similar to that presented in SP 292.1325800.2017: according to a triangular plot with maximum pressure at the bottom. But at the same time, the value of the maximum pressure on the joint venture is about 1.5 times greater than according to the calculation in ANSYS, which is explained by many different factors. But, despite this, modeling of the tsunami waves rolling on the construction site can be performed at the pre-project stage in order to assess the nature of the pressure distribution over the surface of the object, which will allow choosing the most suitable structural and space-planning solutions.
Significant changes in the stress-strain state cause a change in the soil profile of the massif, which is affected by various physical and chemical factors. In particular, groundwater filtration, ...mass transfer, heat transfer, dissolution and leaching of soil masses. This can lead to various types of accidents. Therefore, the study of the stress-strain state of the soil massif is an important topic. Nonlinear dependences in the form of polynomials of the modulus of deformation and Lame coefficients on the concentration of salt solutions and their temperature have been received in this research based on experimental research and their statistical processing. This allowed improving the mathematical model of the stress-strain state of the soil taking into account the nonlinear deformation processes occurring in the soil masses under the presence and filtration of saline solutions in non-isothermal conditions.
Hypotheses and prerequisites for modelling the stress-strain state of the normal cross-section of wooden elements for subsequent calculation using the deformation method are proposed. Stages of the ...stress-strain state of solid and glued wood elements are presented. The concept of the “design cross-section” with a fold in the compressed zone of the element is proposed.
Based on previously performed calculations of the load-bearing capacity for the ultimate and serviceability limit states, an experimental design of a rafter arch was developed. New results from ...experimental studies on the stress-strain state of its components were obtained, specifically for the semi-arches, ties, and struts under the influence of symmetrical and asymmetrical loads. According to the proposed methodology, a full-scale sample of a steel arch structure was studied in accordance with the loading schemes that are possible in practice. As a result, the actual stresses in all elements were determined, considering both the inclusion and exclusion of preliminary stress. The main theoretical prerequisites for the calculation of the rafter arch, proposed by the authors under the methodology, have been validated. The research objectives were formulated for the subsequent experimental and theoretical investigations of continuous perforated elements. The focus is on establishing effective structural solutions for intermediate supports based on various factors, including size, nature (static or dynamic), type (concentrated, evenly distributed, combined), load action scheme, material strength (standard or high-strength steels), span size, and geometric parameters of the section. Distinct variations are considered concerning the presence or absence of stiffeners along the axis of the intermediate support and the inclusion of welded or non-welded perforation holes on the left and right of the support. It was determined that the stress distribution in the calculation points of characteristic cross-sections with holes of the bearing part of the non-separated perforated beam near the intermediate support significantly differs from the stress distribution in the span part, since the sign of the bending moment curve changes from positive in the span to negative at the support.
The article deals with the technique of predicting the durability of structural materials under the influence of low-cycle loads at different loading trajectories in a two-dimensional stress space at ...a flat stress-strain state. The use of this technique significantly reduces the number of time-consuming and expensive experiments while maintaining the quality of the results. The technique is based on the method of processing acoustic emission signals when the acoustic signals are allocated with a fractal dimension of the attractor 1≤ D2att ≤6 on a steady-state cyclic creep that reflects the accumulation of hazardous defects in the structural material. To predict the durability at a certain type of stress-strain state, but at any form of a cycle of low-cycle loading by the proposed method, it is enough to have the results of experiments at the maximum intensity of stresses, the minimum intensity of stresses and the saw-tooth form of the cycle of stress intensity change.
