scholarly journals Using the criterion of resistibility to assess of a structural limit state

Vestnik MGSU ◽  
2021 ◽  
pp. 1559-1566
Author(s):  
Anatoly V. Perelmuter
Keyword(s):  
Bearing Capacity ◽  
Limit State ◽  
Limit Load ◽  
External Action ◽  
Equilibrium States ◽  
Structural Elements ◽  
Subjective Assessments ◽  
Calculation Methodology ◽  
Generalized Force ◽  
Variable Interaction

Introduction. Subject of research: behaviour characteristics of an arbitrary structure under the loads that approach the limit load value. Goals: development of an objective and sufficiently universal methodology for the identification of the bearing capacity of a structure, which could allow to stop using any subjective assessments of their limit bearing capacity. Materials and methods. Behaviour characteristics are assessed by analyzing a curve of equilibrium states. The curve is constructed using the characteristic displacement, understood as the generalized displacement q, which energetically matches applied generalized force λ in the sense that the product of λdq is the growth of work performed by generalized force λ in respect of the growth of displacement dq. Results. The article shows that the system’s response, no matter what fixed conditions it is in, is not always sufficient for the assessment of the reliability of the system in case of the variable interaction with the environment. The co-authors use the V.V. Katyushin concept about supplementing the notion of the limit state with the characteristics of the system’s beha­viour determined by the velocity of a change in the system’s response caused by the change in the external action. According to the co-authors’ suggestion, the meter should represent the reduction in the slope of the curve of equilibrium states, which characterizes the loss of resistibility and, consequently, it can be used to assess the closeness of the structure to the state of failure, which arises if the resistibility of the system is equal to zero. The suggestion is to use the value of the slope of the curve of equilibrium states as the limit state, when the resistibility has reduced, and the velocity of deformation intensification has gone up 100 times if compared with the behaviour of an unloaded system. This suggestion is illustrated by the case of the analysis of a reinforced concrete diaphragm of a building. Conclusions. The proposed calculation methodology can be applied in the design of loadbearing structural elements, whose finite-element computational model has components that are different from the rod ones.

scholarly journals LOAD-BEARING CAPACITY ANALYSIS OF BUILDING PARTITIONS OF THE COLD STORAGE CHAMBERS

2019 ◽  
Vol 81 (2) ◽  
pp. 240-248
Author(s):  
R. Chmielewski ◽  
L. Kruszka ◽  
L. Muzolf
Keyword(s):  
Bearing Capacity ◽  
Cold Storage ◽  
Limit State ◽  
Technical Condition ◽  
Capacity Analysis ◽  
Structural Elements ◽  
Current Load ◽  
Structural Element ◽  
Load Bearing Capacity ◽  
Load Bearing

The paper presents problems related to the load-bearing capacity analysis of the building partitions of the cold storage facility. The subject of the case study are two different buildings built in the early fifties of the last century. Despite the similar cubature and the construction period, the structures of these buildings are different. The analysed cold store in Warsaw (Poland) is a steel and brick structure, while the second example concerns a reinforced concrete slab-pillar structure located in Wloclawek (Poland). In both cases, the issue related to the assessment of the current technical condition of the structural elements, including the safety of the load-bearing structure and the safety of its use was considered. Moreover, the permissible load for inter-storey slabs in both cases was determined. In order to properly determine the current load-bearing capacity of inter-story slabs, the archival technical and operational documentation of buildings was firstly analysed. Their technical condition was also taken into account in the assessment process. In-situ inspections of both buildings had been carried out. This allowed the determination of the scope of necessary tests and the selection of test and check points for each structural element. Such actions allowed to identify cross-sections of the structural elements and the parameters of built-in materials. The performed diagnostics also allowed to properly determine the technical condition of each structural element, the degree of degradation of the structure and to correctly determine its current load-bearing capacity while simultaneously satisfying both limit states - the Ultimate Limit State (ULS) and the Serviceability Limit State (SLS).

Highways Design Taking into Account Climatic Features in the Route Area

2021 ◽  
pp. 125-136
Author(s):  
Т. В. Самодурова ◽  
Н. Ю. Алимова ◽  
О. А. Волокитина ◽  
О. В. Гладышева
Keyword(s):  
Bearing Capacity ◽  
Computer Aided Design ◽  
Systematic Approach ◽  
Weather Conditions ◽  
Design Stage ◽  
Design System ◽  
Computer Aided ◽  
Calculation Methodology ◽  
Aided Design ◽  
Climatic Features

Постановка задачи. Для получения оптимальных проектных решений, удовлетворяющих условиям безопасности движения в сложных погодных условиях, необходимо сравнение вариантов автомобильных дорог по условиям снегонезаносимости. Такие расчеты должны стать составной частью системы автоматизированного проектирования САПР-АД. Результаты. Предложен системный поход к решению задачи, определен перечень информации, необходимой для проведения расчетов. Выполнен анализ результатов исследований по снегозаносимости дорог, проводимых в России и за рубежом. Предложены расчетные схемы и модели для оценки вариантов продольного профиля и земляного полотна автомобильной дороги по снегозаносимости. Предложены решения для оценки вариантов плана трассы с использованием карт с расчетными параметрами метелей. Выводы. Реализация предложенной методики проведения расчетов позволит на стадии проектирования оценить варианты автомобильной дороги по условиям снегозаносимости. Statement of the problem. In order to obtain optimal design solutions that meet the conditions of safety traffic in difficult weather conditions, it is necessary to compare the options of highways according to the snow tolerance conditions. Such calculations should become an integral part of the CAD-AD computer-aided design system. Results. A systematic approach to solving the problem is set forth, a list of information necessary for calculations is identified. The results analysis of studies on the snow-bearing capacity of roads conducted in Russia and abroad is carried out. Calculation schemes and models are suggested to evaluate options for the longitudinal profile and the roadbed for the snow-bearing capacity. Solutions for evaluating variants of the route plan using maps with calculated parameters of snowstorms are proposed. Conclusions. The implementation of the proposed calculation methodology will make it possible at the design stage to evaluate the options of the highway according to the conditions of the snow-bearing capacity.

Bearing capacity of a threaded pair made of spatially reinforced carbon-carbon composite materials at high temperatures

2021 ◽  
pp. 30-34
Author(s):  
Keyword(s):  
Composite Materials ◽  
Bearing Capacity ◽  
High Temperatures ◽  
Limit Load ◽  
Carbon Composite ◽  
Reinforcement Scheme ◽  
Carbon Composite Material ◽  
Carbon Composite Materials ◽  
Threaded Joints ◽  
Joint Limit

The bearing capacity of a threaded pair made of spatially reinforced carbon-carbon composite materials (CCCM) with a 4DL reinforcement scheme in the temperature range from 20 to 2500 °C is experimentally determined. Recommendations are given for the design of CCCM threaded joints for operation at high temperatures. Keywords: carbon-carbon composite material, threaded joint, limit load, bearing capacity, threaded pair, high temperature. [email protected]

scholarly journals Influence of loading level on the bearing capacity of RC columns strengthened by jacketing

2018 ◽  
Vol 230 ◽  
pp. 02013 ◽  
Author(s):  
Pavlo Krainskyi ◽  
Yaroslav Blikharskyy ◽  
Roman Khmil ◽  
Pavlo Vegera
Keyword(s):  
Reinforced Concrete ◽  
Bearing Capacity ◽  
Limit State ◽  
Real Life ◽  
Load Level ◽  
Reinforced Concrete Structure ◽  
Multistory Buildings ◽  
Loading Level ◽  
Industrial Buildings ◽  
Service Load

Compressed reinforced concrete elements are quite common in construction. An example of such elements is the columns of industrial buildings, which are loaded with eccentric force, for example, from a bridge crane, columns of multistory buildings, structures subjected to compression and bending. When the reinforced concrete structure becomes unfit to future operation, it is often more economical and easy to retrofit it than to change it for a new one. Most of these structures are influenced by certain loads and unloading the structures before strengthening is not always possible. Therefore, in this work reinforced concrete structures strengthened by jacketing are investigated. To simulate the real life conditions, the loading level of 65-70% of the not strengthened column bearing capacity was maintained during jacketing. This load level simulates the actual service load on the structure. The bearing capacity load and serviceability limit state of not strengthened and jacketed reinforced concrete columns were investigated and the experimental results are presented in this paper.

Evaluation on Safety of In-Service Structures Concerning Earthquake Resistance Based on Fourth-Order Moment of Limit State Function

2014 ◽  
Vol 1065-1069 ◽  
pp. 2319-2322
Author(s):  
Yu Ying Wang ◽  
Ya Zhou Sun ◽  
Le Yang Feng
Keyword(s):  
Bearing Capacity ◽  
Fourth Order ◽  
Structural Damage ◽  
Limit State ◽  
Decisive Role ◽  
Order Moment ◽  
State Function ◽  
Limit State Function ◽  
Engineering Structures ◽  
Internal Factors

During the process of being used, engineering structures will undergo material aging and structural damage with time passing by under the combined influence of internal factors including load, environment and structural material[1], and accumulation of such damages will cause decrease of bearing capacity, durability and reliability. Among various factors influencing the reliability of in-service structures, ultimate bearing capacity plays the decisive role in safety. In this paper, the fourth-order moment of limit state function is inferred through calculation of failure probability of in-service structures, and thus safety and durability of in-service structures can be ensured.

Upper bound to bearing capacity of layered soils

1989 ◽  
Vol 26 (4) ◽  
pp. 730-736 ◽  
Author(s):  
Antoni Florkiewicz
Keyword(s):  
Experimental Data ◽  
Bearing Capacity ◽  
Limit State ◽  
Layered Soils ◽  
Flat Punch ◽  
Layer System ◽  
Capacity Limit ◽  
Strip Footings ◽  
Kinematical Approach ◽  
Layered Half Space

An approach to the problem of flat punch indentation into the Mohr-Coulomb layered half-space has been developed, based on the kinematical approach of limit analysis. A kinematically admissible plane-strain failure mechanism for a typical two-layer system is presented. The ultimate bearing capacity for strip footings obtained from the proposed approach compares well with the experimental data available in the literature. Key words: bearing capacity, limit state analysis, layered soil, strip footings.

Limit Load Analysis of Crack Contained Thick Walled Cylinders

2010 ◽  
Author(s):  
Saeid Hadidi-Moud ◽  
David John Smith
Keyword(s):  
Plastic Deformation ◽  
Limit State ◽  
Limit Load ◽  
Combined Loading ◽  
Finite Element Analyses ◽  
Limit Loads ◽  
Integrity Assessment ◽  
Crack Configuration ◽  
Load Analysis

Reliable limit load estimations for thick walled pressurized cylinders containing defects are required for the assessment of integrity of structures that experience significant plastic deformation prior to failure. Analytical and finite element analyses of limit load in thick walled cylinders containing defects are presented in this paper. FE analyses were conducted to obtain estimates of the limit state of loading for a range of combined loading schemes and loading sequences for open-end and closed-end cylinder. Part through shallow and deep hoop cracks in the cylinder for uniform radial, uniform axial and combined loading were examined. The results suggest that adjustments to the estimates of limit loads obtained from conventional methods reported in literature are needed in order to reflect the role of material response, crack configuration and boundary conditions on the limit loads of defected thick walled pipes and cylinders. These findings are very important and should be noted carefully, especially in the context of treatment of hoop and axial residual stresses in the integrity assessment of pipelines containing part through cracks.

Limit Analysis for Anisotropic Solids Using Variational Principle and Repeated Elastic Finite Element Analyses

2002 ◽  
Author(s):  
L. Pan ◽  
R. Seshadri
Keyword(s):  
Finite Element ◽  
Variational Principle ◽  
Limit State ◽  
Limit Load ◽  
Anisotropic Materials ◽  
Stress Fields ◽  
Finite Element Analyses ◽  
Structural Components ◽  
Directionally Solidified ◽  
Elastic Compensation Method

Many structural components, such as rolled sheets, directionally solidified superalloys and composites, are made of anisotropic materials. The knowledge of limit load is useful in the design and the sizing of these components and structures. This paper presents the extension of the modified mα-method to anisotropic materials. Mura’s variational principle is employed in conjunction with repeated elastic finite element analyses (FEA). The secant modulus of the discretized finite elements in the reference direction in successive elastic iterations is used to estimate the plastic flow parameter for the anisotropic components. The modified initial elastic properties are adopted to ensure the “elastic” stress fields satisfy the anisotropic yield surface. Using the notion of “leap-frogging” to limit state, improved lower-bound limit loads can be obtained. The formulation is applied to two anisotropic components, and the limit load estimates are compared with those using elastic compensation method and inelastic FEA.

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