Practice for Developing Accelerated Tests to Aid Prediction of the Service Life of Building Components and Materials

10.1520/e0632 ◽  
2005 ◽  
Author(s):  
Keyword(s):  
Service Life ◽  
Accelerated Tests ◽  
Building Components

scholarly journals Prediction analysis of the degradation and the service life building components in artificial method neural network and ISO factor 15686-2

2019 ◽  
Vol 258 ◽  
pp. 03017
Author(s):  
Siti Aisyah ◽  
Akhmad Aminullah ◽  
H. Muslikh
Keyword(s):  
Neural Network ◽  
Service Life ◽  
Predictive Analysis ◽  
Calculation Formula ◽  
Factors Affecting ◽  
Life Planning ◽  
Close Relationship ◽  
Building Components ◽  
Input Variables ◽  
Building Condition

The research study reported in this paper aims to combine the Artificial Neural Networks with ISO 15686 Buildings and constructed assets - Service life planning, a framework-based approach to offering a more reliable deterioration forecasting more reliable for building. This paper discusses the existing data and develop a close relationship definition between factors affecting the condition of the service life of the building, the value of building condition and determine the level of degradation of the building component, also predicted the age of the building components in accordance with a specific time variables. Data examination conducted in this research is building condition data of student dormitory at the Universitas Gadjah Mada, the data will be used to calibrate the model of damage to consider a number of factors that influence. To help demonstrate the concept, factors affecting the decline is considered in the analysis of the design level, the level of implementation of the work, the indoor environment, the external environment, the level of care and conditions of use. Predictive analysis with artificial methods of neural network (ANN) with ISO factor input variables and factors age of the building components and the severity level of degradation of the building components (Sw) as output, this will generate a calculation formula that shows the effect of each variable input to output. Predictive analysis carried out with the reverse approach in which after calculation formula obtained by ANN method, then the next step is to find the value of the variable age of the building components according to the value of degradation that has been determined.

Dynamic Life Prediction of RC Structures on Multi-Environmental Time Similarity Method

2011 ◽  
Vol 255-260 ◽  
pp. 220-224 ◽  
Author(s):  
Wei Liang Jin ◽  
Zhi Yuan Li ◽  
Ju Chen ◽  
Jin Quan Wang ◽  
Xiao Zhou Wang
Keyword(s):  
Service Life ◽  
Natural Environment ◽  
Life Prediction ◽  
Indoor Environment ◽  
Prior Information ◽  
Service Life Prediction ◽  
Accelerated Tests ◽  
Rc Structures ◽  
Similarity Method

Multi-environmental time similarity (METS) stepped forward for solving the key technique of service-life correlation of reinforced concrete (RC) structures exposed in artificially accelerated and real natural environment. Artificially accelerated tests and the similarity relationship between natural and indoor environment are used to estimate the prior information. Inspections of the real structure and concrete specimens are used to update the information and reduce the uncertainty in the service-life prediction. The progress of service-life prediction becomes dynamic and long-term.

scholarly journals Methods for estimating the durability of the needle bearing of the piston head of the connecting rod of a transportation diesel

2021 ◽  
pp. 55-60
Author(s):  
Vadym Mychaylovich Petuhov ◽  
Alexandr Vasilyevich Orobinsky ◽  
Natalya Anatolyevna Aksenova
Keyword(s):  
Diesel Engine ◽  
Service Life ◽  
Test Procedure ◽  
Operating Conditions ◽  
Accelerated Tests ◽  
Connecting Rod ◽  
Design Work ◽  
Engine Operation ◽  
Piston Head ◽  
Rolling Elements

The article presents the results of an experimental study and analytical evaluation calculations to check service life and increase durability of the needle bearing of piston head of connecting rod of a transport diesel engine. The primary reasons for the violation of the nominal operation of the main units of this mechanism have been established. Corresponding recommendations are proposed for carrying out accelerated tests for durability, reducing the thermal loads of the bearing operation and, as a consequence, improving the quality and service life of its entire piston group. Theoretical and experimental methods for determining the nominal life of the needle bearing of the piston head of the connecting rod (PHCR) of a transport diesel engine are proposed. The theoretical methodology allows obtaining reliable values of durability, taking into account the distribution of the working load over the rolling elements, as well as the mobility of the piston pin and sleeve. The performed calculations make it possible to correct and clarify the standard mathematical model for determining the nominal life of the PHCR needle bearing, depending on the distribution of loads on the rolling elements (rollers) under different operating conditions. This experimental technique with an acceleration factor of 10 is based on a twofold increase in the force effect on the elements of the PHCR needle bearing. This was achieved by assembling the bearing using a special technology, which is described in detail in the work. A significant decrease in the thermal effect and a decrease in radial loads on working rollers have been established. For ensure the regular oil supply into bearing during engine operation, a technique was developed to increase the load on the roller in contact zone, which significantly influenced durability and made it possible to conduct accelerated tests with a reliable yield. Its results of operational research and experience in design work correlate and are sufficiently explained by the developed methods, which allows them to be used for the improvement and modernization of connecting rods with needle bearings in PHCR. That is a permission to use these methodic for doing perfect and modern the needle bearing of the connecting-rod piston. Keywords: diesel, test procedure, needle bearing, rollers, piston head of the connecting rod, durability.

scholarly journals Degradation Assessment of Natural Stone Claddings over Their Service Life: Comparison between Tehran (Iran) and Lisbon (Portugal)

Buildings ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 438
Author(s):  
S. H. Mousavi ◽  
Ana Silva ◽  
Jorge de Brito ◽  
A. Ekhlassi ◽  
S. B. Hosseini
Keyword(s):  
Service Life ◽  
Environmental Exposure ◽  
General Concept ◽  
Natural Stone ◽  
Sustainable Solutions ◽  
Environmental Agents ◽  
Standard Value ◽  
Building Components ◽  
Durable Solutions ◽  
The Impact

Now more than ever, the construction sector is aiming to adopt more sustainable solutions. To achieve this purpose, more durable solutions must be adopted, making rational decisions at the design and maintenance stages regarding the conditions of environmental exposure and use. In this sense, knowledge regarding the service life of building components is crucial. This knowledge should not be a general concept, or a standard value, and adapting practices from one country to another is extremely challenging. In this sense, this study analyses the service life of natural stone claddings. We adopt a methodology initially proposed for Lisbon (Portugal), intending to evaluate its applicability to other geographical contexts, in order to perform a more reliable service life prediction of stone claddings located in Tehran (Iran). An estimated service life of 65 years was obtained for a sample of 162 stone claddings directly adhered to the substrate, located in Tehran, which were analysed by in situ inspections. The impact of different conditions (e.g., type of stone and environmental exposure conditions) on the service life of stone claddings in Tehran was quantified, which revealed that the exposure to environmental agents, such as wind, rain and pollutants, is the main cause of degradation of the natural stone claddings.

Service-life assessment of building components: application of evidence theory

2008 ◽  
Vol 35 (3) ◽  
pp. 287-300 ◽  
Author(s):  
A. Talon ◽  
D. Boissier ◽  
J. Lair
Keyword(s):  
Service Life ◽  
Evidence Theory ◽  
Life Assessment ◽  
Design Stage ◽  
Life Data ◽  
Performance Requirements ◽  
Short Term Exposure ◽  
Building Components ◽  
Building Component ◽  
Service Building

This paper deals with the assessment of the service life of in-service building components subjected to known environmental and usage conditions. This assessment is complex because of two primary features. First, the assessment has to be carried within a multiscale context: a geometric scale that ranges from the material or elemental to building scale; a range in the complexity of the degradation (phenomena that varies from a single phenomenon to the consideration of several degradation scenarios); a range of possible performance requirements, from one function to several; and consideration, as well, to the time over which the process is carried out that may span from the design stage to that of management and repair. Second, this assessment must also take into consideration the availability and features of service-life data that by nature is heterogeneous, imprecise, uncertain, and incomplete. In this context, a comprehensive methodology is developed using all available data on service life derived from existing methods of service-life assessment of materials, elements or building components. Such data may, for example, be extracted from fundamental studies on durability, accelerated short-term exposure tests, statistical methods, factorial methods, feedback from practice, or expert opinion or other sources. The main stages of this methodology are: (i) identification of all possible degradation scenarios provided by failure mode and effects analysis (FMEA); (ii) collection of all available service-life data (SL-data) associated with these degradation scenarios, transformation of this data into a fuzzy-set format, and assessment of its quality; (iii) processing of unification of data and aggregation of data; and (iv) assessment of the service life of building components. The case study of a window unit allows for: (i) service-life assessment of a building component to be processed by unification of data and aggregation of data and (ii) a conclusion to be deduced.

Building Component Maintenance/Repair Management: an Economic Analysis Simulation

2011 ◽  
Vol 94-96 ◽  
pp. 2134-2137
Author(s):  
Nima Amani ◽  
Nasly Bt Mohamed Ali ◽  
Seyedmohsen Hosseini
Keyword(s):  
Service Life ◽  
Economic Analysis ◽  
Condition Index ◽  
Repair System ◽  
Repair Cost ◽  
Maintenance And Repair ◽  
Limited Budget ◽  
Development Tool ◽  
Building Components ◽  
Building Component

Starting, implementation, and operation of building facilities system are very vital, especially under limited budget. To component repair cost decisions, suitable assessment, and accurate prediction of the condition of assets are essential. The purpose of this study is at supporting the condition assessment and predicting the future of component condition by NCES condition metrics. This paper reflects on the NCES condition index process in maintenance and repair system of building components by research in similar subjects and looks specifically at the use of NCES condition index (CI) as a development tool. The result of research can be used as a guide to assist component managers and building owners to make suitable decisions about component appropriate maintenance based on limited budget during its service life.

scholarly journals Impact of Environmental Exposure on the Service Life of Façade Claddings—A Statistical Analysis

Buildings ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 615
Author(s):  
Joana Barrelas ◽  
Ilídio S. Dias ◽  
Ana Silva ◽  
Jorge de Brito ◽  
Inês Flores-Colen ◽  
...  
Keyword(s):  
Statistical Analysis ◽  
Service Life ◽  
Environmental Exposure ◽  
Degradation Process ◽  
Related Factors ◽  
High Exposure ◽  
Tiling System ◽  
Building Components ◽  
The Impact ◽  
Exposure Conditions

Façade claddings, as the outer protection layer of the building’s envelope, are directly exposed to environmental degradation agents. The façades’ orientation and their distance from the sea, among other location and protection-related factors, influence their vulnerability to climate loads, in particular wind and air humidity. These loads, as well as exposure to air pollution, affect the degradation process of claddings and the durability of façades. Therefore, studying the impact of the environmental exposure conditions on the service life of different external claddings provides useful information on their performance over time, which can support (i) decision-makers in the selection of the best façade cladding solutions and (ii) further research on the impact of climate change on building components. This study covers six types of cladding: rendered façades (R), natural stone cladding (NSC), ceramic tiling system (CTS), painted surfaces (PS), external thermal insulation composite systems (ETICS), and architectural concrete façades (ACF). Three hundred façades located in Portugal are analysed according to three main groups of variables, which characterize (i) the façades, (ii) their degradation condition, and (iii) the environmental deterioration loads and context. The statistical analysis results reveal that the environmental variables affect the cladding degradation process. South-oriented façades present lower degradation conditions than façades facing north. The distance from the sea and high exposure to pollutants add to the degradation conditions, reducing the expected service life of façades. The results reveal that claddings can be organized according to two main groups: the most durable (CTS, NSC, and ACF) and the least durable (R, PS, and ETICS) systems. This study enables a comprehensive analysis of the data, useful to draw conclusions about the influence of environmental exposure conditions on the degradation and service life of façade claddings.

The influence of the technical condition of the modernized spray on the service life of a nozzle sprayer of diesel engine

2020 ◽  
pp. 85-91
Author(s):  
Anzor L. Bolotokov ◽  
Valentin P. Lyalyakin
Keyword(s):  
Diesel Engine ◽  
Service Life ◽  
Diesel Engines ◽  
Resistance Coefficient ◽  
Technical Condition ◽  
Research Purpose ◽  
Spray Nozzle ◽  
Accelerated Tests ◽  
Spiral Groove ◽  
Discussion Article

Injectors of diesel engines lose their functionality due to loss of tightness and jamming of the needle of the nozzle sprayer. (Research purpose) The research purpose is increasing the durability of injectors by upgrading the sprayer needle by performing a spiral screw groove on its guiding part. (Materials and methods) The article notes that the screw groove is performed by an elbor cutter on a lathe with the following parameters: an angle of 30 degrees, a radius of 0.133 millimeters, and a length of 21.71 millimeters. Authors conducted research to determine the resistance coefficient of the gap between the sprayer body and the sprayer with a spiral groove, depending on the fuel contamination. Authors performed non-motor bench accelerated tests of sprayers to determine the hydraulic density, the volume of fuel in the screw groove, and the resistance coefficient of the gap. (Results and discussion) Article notes that the decrease rate in the value of hydro density in upgraded sprayers is 1.24 times less than in serial ones. The article shows that due to the screw groove, the needle of the sprayer is rotated, and the working surfaces of the needle are not caught with the sprayer body, which ensures uniform wear with less intensity. (Conclusions) Upgrading the spray nozzle by applying a screw groove to its surface ensures that the surfaces are lubricated and creates a softened twisting impact instead of a hard hit on the spray nozzle seat.

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