CRITERIA FOR EVALUATION OF VENTILATED FACES QUALITY

The article describes an approach to probabilistic and physical modeling of walling reliability taking into account temperature, moisture and operation conditions, structural elements load specifi cation, reliability indicators and failure probability. The durability (service life) is taken as the main reliability indicator. The man-made and climatic impact on building construction durability is studied. It is proved that ventilated faces are a modern design solution for construction of new buildings as well as reconstruction.

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CRITERIA FOR EVALUATION OF VENTILATED FACES QUALITY

URBAN CONSTRUCTION AND ARCHITECTURE ◽

10.17673/vestnik.2017.02.1 ◽

2017 ◽

Vol 7 (2) ◽

pp. 4-8

Author(s):

Kristina A. NETISHINA ◽

Galina N. RYAZANOVA

Keyword(s):

Building Construction ◽

Design Solution ◽

Structural Elements ◽

Climatic Impact ◽

Reliability Indicators ◽

Operation Conditions ◽

Reliability Indicator ◽

Criteria For Evaluation ◽

New Buildings ◽

Account Temperature

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Evaluation of crack resistance of welded joints with soft interlayers

Advanced Engineering Research ◽

10.23947/2687-1653-2021-21-4-308-318 ◽

2022 ◽

Vol 21 (4) ◽

pp. 308-311

Author(s):

K. A. Molokov ◽

V. V. Novikov

Keyword(s):

Experimental Data ◽

Fracture Toughness ◽

Crack Resistance ◽

Welded Joints ◽

Low Cycle Fatigue ◽

Transverse Load ◽

Structural Elements ◽

Metal Structures ◽

Characteristic Appearance ◽

Reliability Indicator

Introduction. Welded joints in large-sized metal structures (e.g., in the structures of ship hulls) subject to low-cycle fatigue are considered. The characteristic appearance of soft interlayers, which are significantly plastically deformed under working loads, was noted. Deformation of the metal structure with damage, especially in the form of cracks, reduces the strength and reliability of structural elements and joints. Pre-deformation negatively affects plasticity; therefore, much depends on the residual plasticity of the cracking material. At the same time, with a decrease in residual plasticity, such an important reliability indicator as the resistance of the material to crack propagation — the fracture toughness – decreases. The paper is devoted to the development of a model that includes analytical dependences for assessing the crack resistance of metal structures and their welded joints with soft interlayers according to the crack resistance limit for all crack sizes.Materials and Methods. The theory and methods of linear mechanics of materials destruction, structural-mechanical approach are used. The calculation results were analyzed and compared to the experimental data and other analytical solutions. The numerical experiment was performed for the ferrite-perlite steel grades of 10, 50, 22K, St3sp, etc., widely used in industry, as well as for alloy steels hardened to medium and high strength of 30KhGSA, 37KhN3A, etc. Results. Analytical dependences are obtained for calculating the relative crack resistance limit according to three main known mechanical characteristics of the state of the material of the soft interlayer of the welded joint.Discussion and Conclusions. The results obtained can be used to assess the crack resistance of pre-deformed structural elements and welded joints (including those with soft interlayers) operating under a transverse load. The results of experimental data and analytical calculations are shown in dimensionless form, which enables to obtain invariant results with respect to the fracture toughness limit.

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Paradigm Shift of New Building in Old Urban Districts: Case Study of Bangkok Chinatown Workshop

E3S Web of Conferences ◽

10.1051/e3sconf/202123605059 ◽

2021 ◽

Vol 236 ◽

pp. 05059

Author(s):

Xian Li ◽

Eakachat Joneurairatana ◽

Veerawat Sirivesmas

Keyword(s):

Paradigm Shift ◽

Building Construction ◽

Symbiotic Relationship ◽

New Paradigm ◽

New Era ◽

Process Of Urbanization ◽

Combination Mode ◽

The City ◽

New Buildings

Architects and designers realize that new buildings cannot completely replace old buildings in the process of urbanization in the world. To establish a method of the new building and the old building coexist and to create the new paradigm of the new building construction in the old district is the responsibility faced by the contemporary architects. This paper first analyzes the old building renovation projects in Berlin and Paris in the 1980s and puts forward the symbiotic relationship between the old and the new buildings in the new era, thus obtaining the research objectives, trying to redefine new buildings and old districts, and creating the new paradigm of contemporary building construction in old districts. Using workshop as an exploration method, this paper conducts data research and sampling analyses on the Chinatown area in Bangkok, and explores the combination mode and paradigm transformation of new buildings and old districts in the city, aiming to seek solutions utilizing art exploration.

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Research and analysis of reliability indicators of individual structural elements of digital substations

Vesti vysshikh uchebnykh zavedenii Chernozem'ya ◽

10.53015/18159958_2021_1_68 ◽

2021 ◽

pp. 68-79

Author(s):

Roman Vladimirovich Klyuev ◽

Madina Tolikovna Plieva ◽

Tamerlan Tamazievich Gudiev ◽

Vladimir Stanislavovich Morkun

Keyword(s):

Structural Elements ◽

Reliability Indicators

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Pneumatic System in a Device for Erosive Wear Tests

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.237.203 ◽

2015 ◽

Vol 237 ◽

pp. 203-208

Author(s):

Wojciech Mizak

Keyword(s):

Erosive Wear ◽

Pneumatic System ◽

Structural Elements ◽

Empirical Modelling ◽

Sustainable Technologies ◽

Erosion Processes ◽

Operation Conditions ◽

Operational Life ◽

Research Problems ◽

Wear Tests

The Institute for Sustainable Technologies – National Research Institute developed a device for erosive wear tests that enables the experimental reconstruction of the erosion process and the empirical modelling with the use of which the assumed operational life of a given material can be determined with reference to the influence of the erosion processes. The author presents the architecture and the functionality of a pneumatic system employed in the device simulating the erosive wear processes. He discusses the functions of individual actuators and the hardware solutions used in this system. Additionally, the research problems encountered during the design and the verification of the prototype of the device are analysed. The instrumentation enables the reconstruction of real operation conditions of structural elements and the simulation of different experimental reactions with the possibility to model their intensity. The developed pneumatic system is an integral part of the device that can be useful for both researchers and designers, because it helps to explain physical aspects of the erosion of materials.

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Method to Increase the Accuracy of Large Crankshaft Geometry Measurements Using Counterweights to Minimize Elastic Deformations

Applied Sciences ◽

10.3390/app10144722 ◽

2020 ◽

Vol 10 (14) ◽

pp. 4722 ◽

Cited By ~ 2

Author(s):

Leszek Chybowski ◽

Krzysztof Nozdrzykowski ◽

Zenon Grządziel ◽

Andrzej Jakubowski ◽

Wojciech Przetakiewicz

Keyword(s):

Elastic Deformation ◽

Measurement System ◽

Design Solution ◽

Structural Elements ◽

Elastic Deformations ◽

Elastic Deflection ◽

Reaction Forces ◽

Geometry Measurement

Large crankshafts are highly susceptible to flexural deformation that causes them to undergo elastic deformation as they revolve, resulting in incorrect geometric measurements. Additional structural elements (counterweights) are used to stabilize the forces at the supports that fix the shaft during measurements. This article describes the use of temporary counterweights during measurements and presents the specifications of the measurement system and method. The effect of the proposed solution on the elastic deflection of a shaft was simulated with FEA, which showed that the solution provides constant reaction forces and ensures nearly zero deflection at the supported main journals of a shaft during its rotation (during its geometry measurement). The article also presents an example of a design solution for a single counterweight.

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Reliability Assessment under Combinations of Snow Load Effect: The Lightweight Steel Structures with Gabled Frames and Components Designs

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.166-169.1954 ◽

2012 ◽

Vol 166-169 ◽

pp. 1954-1957

Author(s):

Ying Chun Cao ◽

Ming Liu ◽

Yuan Qing Wang ◽

Yan Nian Zhang

Keyword(s):

Steel Structures ◽

Dead Load ◽

Reliability Factor ◽

Geometrical Meaning ◽

Load Effect ◽

Snow Load ◽

Non Linear Programming ◽

Lightweight Steel ◽

Reliability Indicators ◽

Reliability Indicator

Purpose: to assess reliability factor of Gable Framed Lightweight Steel Structural and Components, under combination of load effect of permanent loads and snow loads. Method: JC method is adopted in the calculations. From reliability of geometrical meaning, transform the solving of reliability problem into the finding of minimum constraints, and calculate reliability indicators by using a non-linear programming called ‘Lingo’ software. Results: based on dead load plus snow load, and combination of dead load plus snow load and wind load, to calculate reliability indicator of structural components under axial tension, axial compression, and eccentric compression. Conclusion: when combined with snow load, reliability indicator (of Gable Framed Lightweight Steel Structures and Components) is less than the standard permitted reliability indicator, which is beta=3.2.

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Visualization and diagnostics of reliability of the object with changing the functioning conditions

E3S Web of Conferences ◽

10.1051/e3sconf/202126302009 ◽

2021 ◽

Vol 263 ◽

pp. 02009

Author(s):

Evgeny Gvozdev

Keyword(s):

Technological Process ◽

Safety Margin ◽

Operating Conditions ◽

Hazardous Substances ◽

Structural Elements ◽

Base Materials ◽

Reliability Indicator ◽

Margin Of Safety ◽

Fire And Explosion

The object of the scientific research is buildings (structures), which requiring the determination of a reliability indicator for their further operation in new operating conditions, the determination of additional loads in the form of (explosions, fires, vibration processes). The solution to such problems is relevant for buildings (structures), which are acquired (leased) by the owner, for their further operation in the new conditions of the technological process associated with the handling, storage, processing and production of fire and explosion hazardous substances (materials). It is important to determine the readiness of buildings (structures) for operation in the new conditions of functioning of the technological process of production, it is proposed to use deterministic, statistical and probabilistic approaches. It is proposed to use a simplified assessment of the safety margin of a building (structure) by yield strengths (for steel elements) and strength (for base materials, load-bearing walls, partitions and ceilings) corresponding to the maximum allowable values for their destruction. The innovative approach is described that allows us to solve the problems of assessing the strength reliability of structural elements of buildings (structures) to obtain guaranteed characteristics of a given margin of safety, its resistance to possible realized effects (explosions, fires, vibration processes)

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Glulam beams reinforced with FRP strips and their application in architecture

Spatium ◽

10.2298/spat1432001s ◽

2014 ◽

pp. 1-6 ◽

Cited By ~ 3

Author(s):

Radivoj Solarov ◽

Milan Glisic

Keyword(s):

Cost Efficiency ◽

Software Package ◽

Static Load ◽

Original Research ◽

Structural Elements ◽

Pure Bending ◽

Load Bearing Capacity ◽

Fem Model ◽

Frp Strips ◽

New Buildings

This paper emphasizes the advantage of using carbon polymers while producing and strengthening glulam beams. Due to advanced research carried out in this field, the first application of carbon polymers based products was implemented in Western countries. Structural elements containing carbon polymers, or being reinforced by them, show higher resistance and durability properties, as well as the ability to be produced in various shapes. These features can find best application in architecture so the architects? imagination in design could be realized. Many attractive buildings were constructed over the last decade, each of them showing exceptional safety, resistance to atmospheric influences, durability and cost-efficiency. Beside application of carbon polymers in the construction of new buildings, they are even more important in the field of historic heritage restoration. The original research carried out on ten samples in the laboratory is presented in the second part of the paper. Position of the reinforcement on the samples was chosen as it would be done in practical retrofit cases. Deformations of the samples exposed to pure bending were measured, so their behaviour in the elastic range could be analysed based on the results. Measured results were compared to those calculated by using FEM model, developed with software package AxisVM. Based on performed analysis, the conclusion was made that by strengthening timber glulam beams with FRP strips, the simple and efficient static load bearing capacity upgrade is gained.

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Below-Grade Expansion Joints: Challenges and Best Practices

IABSE Congress, New York, New York 2019: The Evolving Metropolis ◽

10.2749/newyork.2019.2610 ◽

2019 ◽

Author(s):

Marisa L. Turner ◽

Rose F. McClure

Keyword(s):

Best Practices ◽

Best Practice ◽

Shear Walls ◽

Groundwater Table ◽

Structural Elements ◽

Structural Walls ◽

Expansion Joints ◽

Design Considerations ◽

New Buildings ◽

Structural Separation

Many of our cities are running out of usable construction space for large buildings. New buildings are reaching new heights and new depths, often extending several stories below-grade. This presents challenges for waterproofing, particularly when building foundations extend below the groundwater table. With climate change and sea-level rise, many geographic areas will increasingly need to consider groundwater.Building code requirements, especially in seismic regions, often require engineers to design movement joints or separation joints in below-grade structures. But foundation waterproofing materials are designed to seal around a building, not a void or an excavation. Structural joints are more susceptible to leakage, and higher volumes of leakage, than areas with solid backup.We review design considerations for movement joints and present two case studies: a parking structure with structural separation joints between exterior shotcrete shear walls; and a hospital campus relying on below- grade expansion joints between buildings with differing foundation systems. In both, the presence of below- grade joints necessitates more complicated detailing and installation.Experience shows us the best practice is to waterproof the building, not the void. Performance is best when the below-grade structural walls provide a solid, continuous substrate. Where movement joints cannot be avoided, we recommend designing structural elements to also meet the needs of the waterproofing system.

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