scholarly journals Increasing the Seismic Resistance of Wood-frame Buildings by Applying PU Foam as Thermal Insulation

2019 ◽  
Author(s):  
Wojciech Migda ◽  
Marcin Szczepański ◽  
Robert Jankowski
Keyword(s):  
Structural Damage ◽  
Residential Buildings ◽  
Substantial Reduction ◽  
Mineral Wool ◽  
Seismic Resistance ◽  
Insulation Material ◽  
Seismic Behaviour ◽  
Pu Foam ◽  
Frame Buildings ◽  
Wood Frame

Wood-frame buildings are very common in regions that are exposed to earthquakes. Most of residential buildings are constructed using this technology; therefore, the seismic resistance of them is really essential in order to prevent human losses and structural damage. The aim of the present article is to show the results of the detailed numerical FEM analysis focused on the seismic behaviour of the wood-frame house with different in-wall insulation materials. The results of the study clearly indicate that using polyurethane (PU) foam instead of mineral wool leads to the increase in the rigidity of the structure and, therefore, to the substantial reduction in the structural response under different seismic excitations. The results also show that, generally speaking, the level of reduction in the displacement response increases with the increase in the magnitude of the earthquake, which even furthermore benefits the application of PU foam as an insulation material. It has also been concluded that the method of using PU foam can be successfully applied not only in the newly constructed wood-frame houses but also in existing ones since replacing the mineral wool with PU foam is relatively easy and not so much expensive.

scholarly journals Insulation systems for buildings and structures based on expanded polyethylene

2018 ◽  
Vol 251 ◽  
pp. 01014 ◽  
Author(s):  
Vyacheslav Semenov ◽  
Sergey Kozlov ◽  
Alexey Zhukov ◽  
Karen Ter-Zakaryan ◽  
Ekaterina Zinovieva ◽  
...  
Keyword(s):  
Mineral Wool ◽  
Expanded Polystyrene ◽  
Insulation Material ◽  
Air Infiltration ◽  
Frame Buildings ◽  
Long Time ◽  
Insulation Systems ◽  
Lock Joint ◽  
Seamless Connection ◽  
Modern Technologies

Insulation systems for buildings and structures imply the use of efficient thermal insulation products based on mineral wool, expanded polystyrene, expanded polyurethane, etc. For a long time, products from non-cross-linked expanded polyethylene were used as insulation for pipelines, reflective insulation, protection against air infiltration, etc. Modern technologies and engineering solutions allowed widening the field of application of non-cross-linked expanded polyethylene (NXLPE) as a construction insulation material. In particular, we can consider a complex of insulation systems for walls, floors and a pitched roof, which allows to form a fully insulating shell of a low-rise building, e.g. a cottage. The novelty of the patented technology Tepofol® and that of the material concerned in comparison with the known solutions is the development of a rolled material based on NXLPE (20 to 150 mm thick) with a lock joint, as well as the technology of seamless connection of individual heat-insulating cloths. The rolls of NXLPE are mechanically fixed to the frame and connected with the lock. One of the advantages of expanded polyethylene, which only few insulating materials possess, is the possibility of forming seamless insulating shells. The article considers a number of insulation systems based on the use of products from expanded polyethylene. In particular, these are the systems of insulation of the walls of frame buildings, the insulation of floors, as well as the insulation of logistics facilities and hangars.

Nonlinear Time-History Analysis of a Six-Story Wood Platform Frame Buildings in Vancouver, British Columbia

2012 ◽  
Vol 28 (2) ◽  
pp. 621-637 ◽  
Author(s):  
Chun Ni ◽  
Shiling Pei ◽  
John W. van de Lindt ◽  
Steven Kuan ◽  
Marjan Popovski
Keyword(s):  
British Columbia ◽  
Seismic Performance ◽  
Numerical Study ◽  
Residential Buildings ◽  
Time History ◽  
Building Code ◽  
Nonlinear Time History Analysis ◽  
Frame Buildings ◽  
Wood Frame ◽  
Nonlinear Time History

In 2009, the British Columbia Building Code was amended to increase the allowable height of wood-frame residential buildings to six stories from four stories. This paper presents the details of a numerical study undertaken to understand the seismic performance of six-story wood-frame buildings designed in accordance with the 2006 British Columbia Building Code. To investigate the seismic behavior, a four-story building was used to represent the benchmark seismic performance prior to the amendment. Two independent analyses using computer programs DRAIN-3DX and SAPWood were carried out on representative buildings located in the city of Vancouver, BC, using a suite of 20 earthquake records scaled to the design seismic hazard level for the site. The analyses showed that six-story wood-frame buildings had similar performance to four-story wood-frame buildings.

scholarly journals Construction and insulation of agricultural buildings and structures

2020 ◽  
Vol 164 ◽  
pp. 02030
Author(s):  
Boris Efimov ◽  
Oleg Rubtsov ◽  
Igor Bessonov ◽  
Andrey Medvedev
Keyword(s):  
Residential Buildings ◽  
Sandwich Panels ◽  
Mineral Wool ◽  
Internal Environment ◽  
Excessive Heat ◽  
Protection Systems ◽  
Insulation Systems ◽  
Weather Impacts ◽  
Storage Facilities

The article covers different application aspects of the products made of polyethylene foam within the scope of insulation systems of framed and frameless constructions used in the quality of storage premises, logistic objects, agricultural storage facilities and livestock facilities as well as framed residential buildings. Agricultural storage facilities, livestock facilities, covered parking areas for agricultural machinery and some types of storage premises represent the agricultural construction facilities which require the established protection systems against excessive heat losses as well as monitoring of the state of the internal environment - its temperature and humidity. These structures are built based on one of three schemes: frameless type, framed type with a rigid coating and framed type with a tent coating. The insulation of buildings constructed before 2010 is predominantly characterized by usage of mineral wool plates (with a protective facade covering) or sandwich panels. The main problem of suchlike coverings is the impossibility of creating an insulating coating without joints, seams or gapless junctions to the base. Mineral wool plates, in case of destruction of the waterproof coating, contact with water and firstly lose their thermal and physical properties, and then – come to the destruction themselves. Sandwich panels are more resistant to weather impacts, but create a coating with huge quantity of cold bridges and paths of convective air transfer through gaps or openings.

Wind Performance Enhancement Strategies for Residential Wood-Frame Buildings

2018 ◽  
Vol 32 (3) ◽  
pp. 04018024 ◽  
Author(s):  
Hassan Masoomi ◽  
Mohammad R. Ameri ◽  
John W. van de Lindt
Keyword(s):  
Performance Enhancement ◽  
Frame Buildings ◽  
Wood Frame

scholarly journals Ventilator-induced diaphragm dysfunction in critical illness

2018 ◽  
Vol 243 (17-18) ◽  
pp. 1331-1339 ◽  
Author(s):  
Yung-Yang Liu ◽  
Li-Fu Li
Keyword(s):  
Oxidative Stress ◽  
Mechanical Ventilation ◽  
Muscle Atrophy ◽  
Structural Damage ◽  
Molecular Mechanisms ◽  
Substantial Reduction ◽  
Mechanical Stretch ◽  
Janus Kinase ◽  
Diaphragm Muscle ◽  
Diaphragm Dysfunction

Mechanical ventilation is an essential intervention for intensive care unit patients with acute lung injury. However, the use of controlled mechanical ventilation in both animal and human models causes ventilator-induced diaphragm dysfunction, wherein a substantial reduction in diaphragmatic force-generating capacity occurs, along with structural injury and atrophy of diaphragm muscle fibers. Although diaphragm dysfunction, noted in most mechanically ventilated patients, is correlated with poor clinical outcome, the specific pathophysiology underlying ventilator-induced diaphragm dysfunction requires further elucidation. Numerous factors may underlie this condition in humans as well as animals, such as increased oxidative stress, calcium-activated calpain and caspase-3, the ubiquitin–proteasome system, autophagy–lysosomal pathway, and proapoptotic proteins. All these alter protein synthesis and degradation, thus resulting in muscle atrophy and impaired contractility and compromising oxidative phosphorylation and upregulating glycolysis associated with impaired mitochondrial function. Furthermore, infection combined with mechanical stretch may induce multisystem organ failure and render the diaphragm more sensitive to ventilator-induced diaphragm dysfunction. Herein, several major cellular mechanisms associated with autophagy, apoptosis, and mitochondrial biogenesis—including toll-like receptor 4, nuclear factor-κB, Src, class O of forkhead box, signal transducer and activator of transcription 3, and Janus kinase—are reviewed. In addition, we discuss the potential therapeutic strategies used to ameliorate ventilator-induced diaphragm dysfunction and thus prevent delay in the management of patients under prolonged duration of mechanical ventilation. Impact statement Mechanical ventilation (MV) is life-saving for patients with acute respiratory failure but also causes difficult liberation of patients from ventilator due to rapid decrease of diaphragm muscle endurance and strength, which is termed ventilator-induced diaphragmatic damage (VIDD). Numerous studies have revealed that VIDD could increase extubation failure, ICU stay, ICU mortality, and healthcare expenditures. However, the mechanisms of VIDD, potentially involving a multistep process including muscle atrophy, oxidative loads, structural damage, and muscle fiber remodeling, are not fully elucidated. Further research is necessary to unravel mechanistic framework for understanding the molecular mechanisms underlying VIDD, especially mitochondrial dysfunction and increased mitochondrial oxidative stress, and develop better MV strategies, rehabilitative programs, and pharmacologic agents to translate this knowledge into clinical benefits.

scholarly journals Timber frame houses resistant to dynamic loads - seismic analysis

2018 ◽  
Vol 219 ◽  
pp. 01001
Author(s):  
Marcin Szczepański ◽  
Wojciech Migda
Keyword(s):  
Polyurethane Foam ◽  
Considerable Increase ◽  
Seismic Analysis ◽  
Numerical Models ◽  
Mineral Wool ◽  
Seismic Excitations ◽  
Timber Frame ◽  
Frame Building ◽  
Frame Buildings ◽  
Node Displacement

The aim of the article is to present results of seismic analysis results of two real-sized timber frame buildings subjected to seismic excitations. The first model was insulated with mineral wool, the second one with polyurethane foam. Technology and specifications involved in both models construction is based on the previously conducted experimental research on timber frame houses, including wall panels tests, wall numerical models and study on material properties and precisely reflect results of the those research. During the seismic analysis reference node located in buildings were selected. In selected node displacement values were measured and compared between two analyzed models. The results of the numerical analysis presented in the article indicate that the application of polyurethane foam for a skeleton filling of the timber-frame building leads to the increase in stiffness as well as damping of the whole structure, which results in a considerable increase in the seismic resistance of the structure.

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