scholarly journals Environmental Optimization of Precast Concrete Beams Using Fibre Reinforced Polymers

2019 ◽  
Vol 11 (7) ◽  
pp. 2174 ◽  
Author(s):  
R. R. L. (Rick) van Loon ◽  
Ester Pujadas-Gispert ◽  
S. P. G. (Faas) Moonen ◽  
Rijk Blok
Keyword(s):  
Life Cycle ◽  
Precast Concrete ◽  
Rc Beams ◽  
Life Cycle Assessments ◽  
Reinforced Polymers ◽  
Fibre Reinforced Polymer ◽  
Building Components ◽  
Frp Tube ◽  
The Right ◽  
Almost All

Increasing importance is being attached to materials in the life-cycle of a building. In the Netherlands, material life-cycle assessments (LCA) are now mandatory for almost all new buildings, on which basis the building is then awarded a building environmental performance or MPG [Milieuprestatie Gebouwen] score. The objective of this study is to reduce the environmental–economic (shadow) costs of precast reinforced concrete (RC) beams in a conventional Dutch office building, thereby improving its MPG score. Two main optimizations are introduced: first, the amount of concrete is reduced, designing a cavity in the cross-section of the beam; second, part of the reinforcement is replaced with a fibre reinforced polymer (FRP) tube. The structural calculations draw from a combination of several codes and FRP recommendations. Hollow FRP-RC beams (with an elongated oval cavity), and flax, glass, and kenaf fibre tubes yielded the lowest shadow costs. In particular, the flax tube obtained shadow costs that were 39% lower than those of the hollow RC beam (with an elongated oval cavity); which also contributed to decreasing the shadow costs of other building components (e.g., facade), thereby reducing the MPG score of the building. However, this study also shows that it is important to select the right type of FRP as hemp fibre tubes resulted in a 98% increase in shadow costs.

scholarly journals Bond between Fibre-Reinforced Polymer Tubes and Sea Water Sea Sand Concrete: Mechanisms and Effective Parameters: Critical Overview and Discussion

Fibers ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 8
Author(s):  
Johanna Dorothea Luck ◽  
Milad Bazli ◽  
Ali Rajabipour
Keyword(s):  
Bond Strength ◽  
Sea Water ◽  
Effective Parameters ◽  
Reinforced Polymers ◽  
Bond Performance ◽  
Cyclic Behaviour ◽  
Sea Sand ◽  
Fibre Reinforced Polymer ◽  
Frp Tube ◽  
Polymer Tubes

Using fibre-reinforced polymers (FRP) in construction avoids corrosion issues associated with the use of traditional steel reinforcement, while seawater and sea sand concrete (SWSSC) reduces environmental issues and resource shortages caused by the production of traditional concrete. The paper gives an overview of the current research on the bond performance between FRP tube and concrete with particular focus on SWSSC. The review follows a thematic broad-to-narrow approach. It reflects on the current research around the significance and application of FRP and SWSSC and discusses important issues around the bond strength and cyclic behaviour of tubular composites. A review of recent studies of bond strength between FRP and concrete and steel and concrete under static or cyclic loading using pushout tests is presented. In addition, the influence of different parameters on the pushout test results are summarised. Finally, recommendations for future studies are proposed.

MODELS FOR DESCRIBING AND SUPPORTING AUTOMATED SYSTEM SCENARIOS

2020 ◽  
pp. 18-22
Author(s):  
В.П. Хранилов ◽  
П.В. Мисевич ◽  
А.Э. Ермилов
Keyword(s):  
Fuzzy Logic ◽  
Life Cycle ◽  
Automated System ◽  
Just In Time ◽  
Success Factor ◽  
Situational Analysis ◽  
Frame Model ◽  
Information Logistics ◽  
The Right ◽  
The Mathematical Model

В статье представлены модели описания сценариев функционирования автоматизированных систем (АС). Вводится и анализируется категория "жизненный цикл сценариев АС". Наиболее важными этапами жизненного цикла сценария являются следующие: этап формирования событийного набора для формирования сценария, этап выполнения последовательности сценарных событий и этап ситуационного анализа внешней и внутренней среды события. В статье предложена математическая модель функционирования АС, которая используется для поддержки этапа выполнения последовательности сценарных событий и основана на принципе информационной логистики: каждый параметр (набор данных) находится в нужном месте в АС, "точно в срок" и в нужном формате. Для поддержки ситуационного анализа предлагается модифицированная фреймовая модель. Ситуационный анализ используется для разработки алгоритмов событий и определения следующего события в сценарии. Модифицированная фреймовая модель основана на использовании нечетких логических процедур в фреймовой сети. The paper presents models for describing the operating scenarios of automated systems. The authors introduce and analyze the category “the life cycle of automated system scenarios”. The life cycle consists of a sequence of stages. The leading success factor of any scenario is the support of the scenario during all stages of its life cycle. The most important stages of the scenario life cycle are the following: the stage of forming the event set for generating the scenario, the stage of performing the sequence of scenario events and the stage of situational analysis of the external and internal environment of the event. In the article it is proposed to use a theoretical set model in order to select an element from a set of alternatives. The elements are events for designing a scenario. The model uses fuzzy logic and is based on the process of controlling an array of parameters if variants are available. The model is used to support the stage of forming a set of events for generating the scenario. The mathematical model of automated system operation which is used to support the stage of performing the sequence of scenario events is suggested in the article. The model is based on the principle of information logistics: each parameter (a set of data) is in the right place in the automated system, ‘just-in-time’ and in the required format. A modified frame model is proposed to support situational analysis. The situational analysis is used to operate the event algorithms and to determine the next event in the scenario. The modified frame model is based on the use of fuzzy logic procedures in a frame network.

scholarly journals Development of central auditory processes in Polish children and adolescents at the age from 7 to 16 years

2021 ◽  
Author(s):  
Monika Lewandowska ◽  
Rafał Milner ◽  
Małgorzata Ganc ◽  
Elżbieta Włodarczyk ◽  
Joanna Dołżycka ◽  
...  
Keyword(s):  
Children And Adolescents ◽  
School Students ◽  
Frequency Pattern ◽  
Speech In Noise ◽  
Age Related ◽  
Right Ear Advantage ◽  
The Right ◽  
Almost All ◽  
Test Retest Reliability ◽  
Auditory Processes

AbstractThere are discrepancies in the literature regarding the course of central auditory processes (CAP) maturation in typically developing children and adolescents. The purpose of the study was to provide an overview of age – related improvement in CAP in Polish primary and secondary school students aged 7–16 years. 180 children/adolescents, subdivided into 9 age categories, and 20 adults (aged 18–24 years) performed the Dichotic Digit Test (DDT), Duration Pattern Test (DPT), Frequency Pattern Test (FPT), Gap Detection Test (GDT) and adaptive Speech-in-Noise (aSpN). The 12-year-olds was retested after w week. We found the age effects only for the DDT, DPT and FPT. In the right ear DDT the 7-year-olds performed more poorly than all groups ≥12. In the left ear DDT both 7- and 8-year-olds achieved less correct responses compared with the 13-, 14-, 15-year-olds and with the adults. The right ear advantage was greater in the 7-year-olds than in the 15-year-olds and adult group. At the age of 7 there was lower DPT and FPT scores than in all participants ≥13 whereas the 8-year-olds obtained less correct responses in the FPT than all age categories ≥12. Almost all groups (except for the 7-year-olds) performed better in the DPT than FPT. The test-retest reliability for all tests was satisfactory. The study demonstrated that different CAP have their own patterns of improvement with age and some of them are specific for the Polish population. The psychoacoustic battery may be useful in screening for CAP disorders in Poland.

scholarly journals CAD integrated automatic recognition of weld paths

2021 ◽  
Author(s):  
Tuan Anh Tran ◽  
Andrei Lobov ◽  
Tord Hansen Kaasa ◽  
Morten Bjelland ◽  
Ole Terje Midling
Keyword(s):  
Life Cycle ◽  
Spatial Analysis ◽  
Product Life Cycle ◽  
Real Life ◽  
Automatic Recognition ◽  
Integrated Method ◽  
Weld Joints ◽  
Related Information ◽  
Almost All ◽  
Sequential Assembly

AbstractIn this paper, a CAD integrated method is proposed for automatic recognition of potential weld locations in large assembly structures predominantly comprised of weld joints. The intention is to reduce the total man-hours spent on manually locating, assigning, and maintaining weld-related information throughout the product life cycle. The method utilizes spatial analysis of extracted stereolithographic data in combination with available CAD functions to determine whether the accessibility surrounding a given intersection edge is sufficient for welding. To demonstrate the method, a system is developed in Siemens NX using their NXOpen Python API. The paper presents the application of the method to real-life use cases in varying complexity in cooperation with industrial partners. The system is able to correctly recognize almost all weld lines for the parts considered within a few minutes. Some exceptions are known for particular intersection lines located deep within notched joints and geometries weldable through sequential assembly, which are left as a subject to further works.

Performance in Fire of Fibre Reinforced Polymer Strengthened Concrete Beams and Columns: Recent Research and Implications for Design

2014 ◽  
Vol 5 (4) ◽  
pp. 353-366 ◽  
Author(s):  
Mark Green ◽  
Kevin Hollingshead ◽  
Noureddine Bénichou
Keyword(s):  
Conceptual Model ◽  
Concrete Beams ◽  
Design Tool ◽  
Fire Performance ◽  
Reinforced Polymers ◽  
Reinforced Polymer ◽  
Practical Design ◽  
Fibre Reinforced Polymer ◽  
Full Scale Tests ◽  
In Fire

This paper considers the fire performance of concrete beams and columns that have been strengthened with fibre reinforced polymers (FRPs). Results from four recent full-scale tests are presented. A newly developed type of insulation was employed and the thickness of the insulation (15 to 20 mm) was approximately half that provided in earlier tests. All of the members survived four hours of the fire exposure. A conceptual model for design to determine when insulation is required is also presented. Further research needed to fully develop the conceptual model to a more practical design tool is outlined.

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