60 research outputs found
Proceedings of FORM 2022. Construction The Formation of Living Environment
This study examines the integration of building information modelling (BIM) technologies in operation & maintenance stage in the system of managing real estate that helps to reduce transaction costs. The approach and method are based on Digital Twin technology and Model Based System Engineering (MBSE) approach.
The results of the development of a service for digital facility management and
digital expertise are presented. The connection between physical and digital objects is conceptualized
Computational Modelling of Concrete and Concrete Structures
Computational Modelling of Concrete and Concrete Structures contains the contributions to the EURO-C 2022 conference (Vienna, Austria, 23-26 May 2022). The papers review and discuss research advancements and assess the applicability and robustness of methods and models for the analysis and design of concrete, fibre-reinforced and prestressed concrete structures, as well as masonry structures. Recent developments include methods of machine learning, novel discretisation methods, probabilistic models, and consideration of a growing number of micro-structural aspects in multi-scale and multi-physics settings. In addition, trends towards the material scale with new fibres and 3D printable concretes, and life-cycle oriented models for ageing and durability of existing and new concrete infrastructure are clearly visible. Overall computational robustness of numerical predictions and mathematical rigour have further increased, accompanied by careful model validation based on respective experimental programmes. The book will serve as an important reference for both academics and professionals, stimulating new research directions in the field of computational modelling of concrete and its application to the analysis of concrete structures. EURO-C 2022 is the eighth edition of the EURO-C conference series after Innsbruck 1994, Bad Gastein 1998, St. Johann im Pongau 2003, Mayrhofen 2006, Schladming 2010, St. Anton am Arlberg 2014, and Bad Hofgastein 2018. The overarching focus of the conferences is on computational methods and numerical models for the analysis of concrete and concrete structures
12th EASN International Conference on "Innovation in Aviation & Space for opening New Horizons"
Epoxy resins show a combination of thermal stability, good mechanical performance, and durability, which make these materials suitable for many applications in the Aerospace industry. Different types of curing agents can be utilized for curing epoxy systems. The use of aliphatic amines as curing agent is preferable over the toxic aromatic ones, though their incorporation increases the flammability of the resin. Recently, we have developed different hybrid strategies, where the sol-gel technique has been exploited in combination with two DOPO-based flame retardants and other synergists or the use of humic acid and ammonium polyphosphate to achieve non-dripping V-0 classification in UL 94 vertical flame spread tests, with low phosphorous loadings (e.g., 1-2 wt%). These strategies improved the flame retardancy of the epoxy matrix, without any detrimental impact on the mechanical and thermal properties of the composites. Finally, the formation of a hybrid silica-epoxy network accounted for the establishment of tailored interphases, due to a better dispersion of more polar additives in the hydrophobic resin
Applications of MATLAB in Science and Engineering
The book consists of 24 chapters illustrating a wide range of areas where MATLAB tools are applied. These areas include mathematics, physics, chemistry and chemical engineering, mechanical engineering, biological (molecular biology) and medical sciences, communication and control systems, digital signal, image and video processing, system modeling and simulation. Many interesting problems have been included throughout the book, and its contents will be beneficial for students and professionals in wide areas of interest
Behavior of Hybrid NSM Reinforced and Externally Confined Reinforced Concrete Columns under Eccentric Compression –Experimental and Numerical Studies
The effectiveness of hybrid combination of ne
ar surface mounted (NSM) and externally
confined (EC) FRP strengthenin
g on the performance of RC
column elements under uniaxial
eccentric compression is investigated.
In total, ten short RC column elements were cast.
Carbon FRP is used for strengthening due to
its inherent stiffness
and strength properties on
par with other FRP materials. The
columns were strengthened using NSM CFRP laminates,
EC using CFRP fabrics and their hybrid combi
nations. A non-linear finite element model is
developed using ABAQUS and the numerical
model is calibrated using the experimental
results to improve the accuracy of the predict
ions. Experimental results revealed that hybrid
strengthening of RC columns was able to show a
better performance in terms of stiffness,
strength, ultimate displacement ductility
when compared to
other FRP strengthening
techniques. The numerical predictions obtained were
able to better capture the initial
stiffness, peak load and post-peak behavior. Thus, the proposed hybrid strengthening
technique for RC columns possess the capability of
restoring the loss in stiffness, strength
and ductility due to additional bending
moment induced by the eccentric compression
loading
Role of Steel Fibers in Shear Resistance of Beams in Arch Action
Reinforced concrete beams
with discrete hooked-end steel fibe
rs were tested with a shear
span to depth ratio equal to 1.8. Digital im
age correlation (DIC) technique was used to obtain
the full-field displacements from the beam
during the load response. The formation and
propagation of a shear crack which directly
influences the load response and peak load in the
load response of the beam is moni
tored using the displacement fr
om the DIC measurements.
There is a continuous slip across the crack face
s of the shear crack with increasing load
carrying capacity up to the peak load. The shear crack exhibits a dilatant behavior with
increasing slip. Failure in control beams
is brittle which was by the opening of dominant
shear crack in shear span at a small value of
crack opening. At the peak load, the shear crack
pattern in fiber reinforced conc
rete was identical to the crack pattern in the control beam. The
dilatant behavior from
the measured crack opening a
nd crack slip displacements obtained
from the control and the SFRC beams is identical.
The fiber reinforced concrete beams
exhibit a ductile response with a post peak load car
rying capacity even after the continued
opening of the dominant shear crack
Détection du Contour Actif de Différentes Images
La segmentation d'image est le problème de partitionnement d'une image en différentes sous-régions sur la base d'une caractéristique préférée. La segmentation est un domaine de recherche important dans le traitement d'images et joue un rôle important dans la vision par ordinateur et la détection d'objets. Un grand nombre d'approches différentes ont été développées pour traiter le problème de segmentation, y compris les modèles de contour actif (MCA). L'idée fondamentale est d'élaborer une courbe initiale sous certaines contraintes d'une image donnée pour détecter les limites d'objet en minimisant une énergie. Dans ce cadre, cette thèse vise à développer des modèles traitant de problèmes de détection d'objets (segmentation d'images) caractérisés par inhomogénéité d'intensité et des limites bruyantes et mal définies. Pour faire face à ces défis, nous avons proposé un certain nombre de MCAs s'appuyant sur la méthode d’ensemble de niveaux. Le premier combine les informations de contour et de région sur la base d'une fonction de pondération adaptative. La deuxième approche utilise la force de pression signée locale basée-région dans une formulation d’ensemble de niveaux simple et efficace. Enfin, le troisième implémente une segmentation basée contour avec une nouvelle fonction d'arrêt basée sur le motif binaire local (LBP). Les résultats expérimentaux démontrent la grande précision de la segmentation obtenue sur diverses images en niveaux de gris synthétiques et réelles par rapport à l’état de l’art des MCA
Stress-Crack Separation Relationship for Macrosynthetic, Steel and Hybrid Fiber Reinforced Concrete
An experimental evaluation of the crack propaga
tion and post-cracking response of macro
fiber reinforced concrete in flexure is c
onducted. Two types of structur
al fibers, hooked end
steel fibers and continuousl
y embossed macro-synthetic fibers are used in this study. A fiber
blend of the two fibers is evaluated for spec
ific improvements in the post peak residual load
carrying response. At 0.5% volume fraction, both
steel and macrosynthetic fiber reinforced
concrete exhibits load recovery at large
crack opening. The blend of 0.2% macrosynthetic
fibers and 0.3% steel fibers shows a significa
nt improvement in the immediate post peak load
response with a significantly smaller load drop and a
constant residual load carrying capacity
equal to 80% of the peak load. An analytical
formulation to predict fle
xure load-displacement
behaviour considering a multi-linear stress-
crack separation (σ
-w) relationship is developed.
An inverse analysis is developed for obtaining the multi-
linear σ
-w relation, from the
experimental response. The
�
-w curves of the steel and
macrosynthetic fiber reinforced
concrete exhibit a stress recovery after
a significant drop with increa
sing crack opening.
Significant residual load carrying capacity is attained
only at large crack separation. The fiber
blend exhibits a constant residual
stress with increasing crack sepa
ration following an initial
decrease. The constant residual stress is
attained at a small crack separation
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