Crankshaft Durability Prediction - A New 3-D Approach

1992 ◽  
Author(s):  
Jean-Pierre Henry ◽  
John Toplosky ◽  
Marek Abramczuk
Keyword(s):  
Durability Prediction

Modelling the Moisture Induced Risk of Decay for Treated and Untreated Wood Above Ground

Holzforschung ◽  
2000 ◽  
Vol 54 (2) ◽  
pp. 111-118 ◽  
Author(s):  
A. O. Rapp ◽  
R.-D. Peek ◽  
M. Sailer
Keyword(s):  
Moisture Content ◽  
Untreated Wood ◽  
Natural Weathering ◽  
Test Material ◽  
Ground Contact ◽  
Mathematical Relationship ◽  
Durability Prediction ◽  
Laboratory Investigations ◽  
Second Year ◽  
Moisture Vapour

Summary During two years of natural weathering the course of the moisture content of test samples of pine sapwood (Pinus sylvestris L.), Norway spruce (Picea abies L.), oak heartwood (Quercus robur L.) and Douglas fir heartwood (Pseudotsuga menziesii Franco.) was recorded by means of 12,000 individual gravimetric readings. The samples were untreated, treated with a weather protection varnish, or impregnated with melamine resin. The data were evaluated with regard to the number of days per year on which the moisture content of wood exceeded the limit of 25%. From the results of subsequent laboratory investigations into the adsorption of liquid water and moisture vapour desorption using the same test material, it was possible to work out a mathematical relationship (MRI = moisture induced risk index) which correlates closely with the number of days of more than 25% moisture content during the second year of natural weathering. The MRI is proposed as a parameter for the assessment of the protective effect of wood treatments which are intended to reduce moisture content and also for durability prediction of untreated wood in out of ground contact situations.

scholarly journals PROBABILISTIC DURABILITY PREDICTION OF EXISTING BUILDING ELEMENTS

2004 ◽  
Vol 10 (2) ◽  
pp. 107-112 ◽  
Author(s):  
Romualdas Kliukas ◽  
Antanas Kudzys
Keyword(s):  
Reliability Index ◽  
Probability Distributions ◽  
Reliability Assessment ◽  
Reliability Prediction ◽  
Existing Building ◽  
Reliability Indices ◽  
Latent Defects ◽  
Durability Prediction ◽  
Building Elements

An effect of service and proof actions on probabilistic reliability (serviceability, safety and durability) of building elements (components and members) of existing enclosure and bearing structures is under consideration. Time‐dependent models for reliability assessment of elements under sustained variable and multicycle actions are presented. Revised reliability indices of existing elements exposed to service permanent and variable actions are discussed. It is recommended to assess the long‐term reliability index of elements taking into account the effect of latent defects. Truncated probability distributions of physical‐mechanical resistances of elements and an effect of their latent defects on reliability index assessment are taken into account. Methodological peculiarities of durability prediction of elements and avoiding unfounded premature repairs or replacements are analysed. The applied illustration of the presented method on the probabilistic reliability prediction of deteriorating concrete covers is demonstrated.

Multilayer sound absorbing structure durability prediction under cyclic loading

2020 ◽  
Author(s):  
Aleksander N. Anoshkin ◽  
Pavel V. Pisarev ◽  
Denis A. Ermakov ◽  
Kseniya V. Roman
Keyword(s):  
Cyclic Loading ◽  
Durability Prediction

Optimized Durability Prediction of Cast Iron Based on Local Microstructure

2016 ◽  
Vol 11 (2) ◽  
pp. 207-215 ◽  
Author(s):  
Corinna Thomser ◽  
Mathias Bodenburg ◽  
Joerg C. Sturm
Keyword(s):  
Cast Iron ◽  
Durability Prediction ◽  
Iron Based

scholarly journals Analysis of causes of the end of service life of a spray polyurethane foam and polyurea roof

2020 ◽  
Vol 172 ◽  
pp. 15002
Author(s):  
Targo Kalamees ◽  
Simo Ilomets ◽  
Mattias Põldaru ◽  
Paul Klõseiko ◽  
Urve Kallavus ◽  
...  
Keyword(s):  
Service Life ◽  
Polyurethane Foam ◽  
Field Measurements ◽  
High Water ◽  
Climatic Conditions ◽  
Water Vapour Pressure ◽  
Hygrothermal Performance ◽  
Durability Prediction ◽  
Humidity Measurements ◽  
Term Performance

Spray polyurethane foam (SPF) roofs are widely used in North America. Much fewer usage examples and experience can be found in Northern European cold climatic conditions. This study analyses hygrothermal performance and the reasons for the roof’s degradation and end of service life of an SPF and polyurea roof. The service life of the roof is over and major reconstruction is needed eight year after construction. The current study uses field measurements included onsite temperature and humidity measurements and extensive surveying, the roof was opened from several locations and test samples were taken for laboratory tests. The influence of UV radiation on the loss of adhesion was tested. Solar radiation quickly degraded the top surface of the in-situ sprayed polyurethane foam insulation causing a weak connection between the foam layers. Due to mechanically damaged and UV degraded polyurea roofing, water has leaked into the SPF. The water inside or below the foam evaporated during sunny days and broke the adhesion of different foam layers. Larger foam blisters were observed on the upper part of the insulation caused by high water vapour pressure. This is considered the most realistic cause of separation of the SPF layers. The analyse of hygrothermal performance, service life, and durability prediction should be included into the design process, especially for structures with small or without long term performance experience.

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