6 results on '"Masonry Failure"'
Search Results
2. Geometrically modified auxetic polyurethane foams and their potential application in impact mitigation of masonry structures
- Author
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Tatheer Zahra, David Thambiratnam, Yan Zhuge, Tommy H.T. Chan, Mohammad Asad, Asad, Mohammad, Zahra, Tatheer, Thambiratnam, David P, Chan, Tommy HT, and Zhuge, Yan
- Subjects
Absorption (acoustics) ,energy dissipation ,Materials science ,Auxetics ,0211 other engineering and technologies ,020101 civil engineering ,02 engineering and technology ,0201 civil engineering ,chemistry.chemical_compound ,021105 building & construction ,Ultimate tensile strength ,General Materials Science ,polyurethane foam ,Composite material ,Civil and Structural Engineering ,Polyurethane ,auxetic foam ,business.industry ,impactor penetration ,Building and Construction ,Masonry ,Dissipation ,Finite element method ,chemistry ,negative poisson’s ratio ,high-velocity impact ,geometrically modified auxetic foam ,business ,Displacement (fluid) ,masonry failure - Abstract
Refereed/Peer-reviewed Hollow block masonry buildings constructed alongside busy roads are vulnerable to vehicular impacts resulting in damage to property and harm to the building and vehicle occupants. This paper presents a method for the design and insertion of various forms of geometrically modified auxetic foam structures inside the hollow cores of block masonry walls for mitigating the adverse effects of such impacts. Due to the low tensile strength of masonry, the insertion material should possess high energy absorption characteristics and high strength for impact damage mitigation which can be achieved through auxetic foams with negative Poisson's ratio. To this end, finite element models of geometrically modified auxetic foams (GMAFs) are developed by inserting thin polyester sheets and hollow acrylonitrile butadiene styrene (ABS) tubes of various geometries into conventional polyurethane foams. The proposed geometrical configurations of inserted tubes and sheets result in auxetic behaviour of the conventional foam with a maximum negative Poisson's ratio of about-12. These foam models are validated analytically and then employed to model masonry walls with auxetic foam insertions in the hollow cores of blocks. These masonry wall models are then analysed under high-velocity lateral impacts. Results show the beneficial change in the failure mechanism of the masonry walls which altered from severe damage of wall face to the rebound of the impactor without penetration by reducing the displacement by four times, due to the presence of the auxetic foam insertions. This phenomenon occurred due to the significant energy dissipation caused by the combined effects of the re-entrant shaped hollow tubes and thin polyester sheet arrangements in the GMAF. Outcomes of this study will contribute towards safer masonry buildings along busy road fronts.
- Published
- 2021
3. Geometrically modified auxetic polyurethane foams and their potential application in impact mitigation of masonry structures.
- Author
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Asad, Mohammad, Zahra, Tatheer, Thambiratnam, David P., Chan, Tommy H.T., and Zhuge, Yan
- Subjects
- *
FOAM , *URETHANE foam , *POISSON'S ratio , *MASONRY , *ENERGY dissipation , *TENSILE strength - Abstract
• Innovative Geometrically Modified Auxetic foam (GMAF) Structures are developed for impact mitigation. • Incorporation of re-entrant shaped tubes and filaments enhanced the auxetic behaviour of PU foams. • Significant energy dissipation is shown by the developed GMAF Structures. • Application of GMAF to masonry provides impact mitigation. • Ability of GMAF to prevent penetration of impactor into masonry wall is numerically proved. Hollow block masonry buildings constructed alongside busy roads are vulnerable to vehicular impacts resulting in damage to property and harm to the building and vehicle occupants. This paper presents a method for the design and insertion of various forms of geometrically modified auxetic foam structures inside the hollow cores of block masonry walls for mitigating the adverse effects of such impacts. Due to the low tensile strength of masonry, the insertion material should possess high energy absorption characteristics and high strength for impact damage mitigation which can be achieved through auxetic foams with negative Poisson's ratio. To this end, finite element models of geometrically modified auxetic foams (GMAFs) are developed by inserting thin polyester sheets and hollow acrylonitrile butadiene styrene (ABS) tubes of various geometries into conventional polyurethane foams. The proposed geometrical configurations of inserted tubes and sheets result in auxetic behaviour of the conventional foam with a maximum negative Poisson's ratio of about −12. These foam models are validated analytically and then employed to model masonry walls with auxetic foam insertions in the hollow cores of blocks. These masonry wall models are then analysed under high-velocity lateral impacts. Results show the beneficial change in the failure mechanism of the masonry walls which altered from severe damage of wall face to the rebound of the impactor without penetration by reducing the displacement by four times, due to the presence of the auxetic foam insertions. This phenomenon occurred due to the significant energy dissipation caused by the combined effects of the re-entrant shaped hollow tubes and thin polyester sheet arrangements in the GMAF. Outcomes of this study will contribute towards safer masonry buildings along busy road fronts. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
4. Efficient modeling of masonry failure using a multiscale domain activation approach.
- Author
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Driesen, Cedric, Degée, Hervé, and Vandoren, Bram
- Subjects
- *
MASONRY , *MULTISCALE modeling , *LAND subsidence , *FACADES - Abstract
• Multiscale modeling can both accurately and efficiently simulate masonry facades. • The proposed method can be applied to more complex masonry systems. • The efficiency increase is often higher in larger scale structures. A finite element based framework that formulates an adaptive multiresolution multiscale technique is presented, with the goal of both accurately and efficiently simulating large masonry structures. In order to find a compromise between accuracy and computational efficiency a scale embedding multiscale model where both macro- and microscale elements come into play is proposed, combining the advantages both have to offer. This theory is tested and compared with an equivalent microscale model to demonstrate that its accuracy rivals a microscale approach, while at the same time having a higher computational efficiency. The developed multiscale model is compared to its underlying microscale model in a couple of selected example structures, ranging from small to large scale unreinforced masonry walls with openings. An application in the form of soil subsidence is explored, showing a potential for extended applications of this type of modeling. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
5. Seismic Behaviour of Ancient Monuments: From Collapse Observation to Permanent Monitoring
- Author
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Gattulli, Vincenzo and Potenza, Francesco
- Subjects
Monumental Structures ,Seismic Damage, Seismic Vulnerability, Structural Analysis, Masonry Failure, Monumental Structures, Structural Health Monitoring ,Masonry Failure ,Structural Health Monitoring ,Seismic Damage ,Seismic Vulnerability ,Structural Analysis - Published
- 2015
6. Experimental and numerical study of confined masonry walls under in-plane loads : case : guerrero State (Mexico)
- Author
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Sánchez Tizapa, Sulpicio, Laboratoire de Modélisation et Simulation Multi Echelle (MSME), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Université Paris-Est Marne-la-Vallée (UPEM), Université Paris-Est, and Ahmed Mébarki
- Subjects
[SPI.OTHER]Engineering Sciences [physics]/Other ,Charges latérales ,Rupture de la maçonnerie ,Clay solid bricks ,Resistance ,Lateral loads ,Masonry failure ,Mechanical properties ,Résistance à cisaillement ,Modèles simplifiés ,Mortier ,Briques solides ,Mortar joint ,Propriétés mécaniques ,Maçonnerie ,Béton ,Shear strenght ,Masonry ,Simplifies models ,Concrete - Abstract
This research work proposes methods to rises the resistance and to evaluate the behavior of confined masonry walls built from clay solid bricks. These elements are widely used in Guerrero State (México) to build masonry structures, which should resist high lateral loads because of the serious seismic hazard. Therefore, a large experimental program to evaluate the mechanical properties of bricks and masonry currently required in the design process and masonry analysis was developed. To rises the masonry resistance and to counteract the influence of the compressive strength of the pieces on the masonry behavior, a high compressive strength mortar and a metallic reinforcement inside the joints were used. With respect to referenced values of the mechanical properties, some were similar and others were twice bigger. In this country zone, the first three tests under lateral load on full-scale confined masonry walls built from clay solid bricks were carried out in order to evaluate its behavior. A reinforcement composed by metallic hexagonal mesh-mortar coat was placed on the faces of two walls to rise or to restore the resistance. The walls showed good behavior and the reinforcement had adequate structural efficiency. Numerical models of panels and walls built by using the experimental data evaluated the envelope resistance, the failure mode and showed the influence of the mechanical properties of the pieces and joints on the global behavior. Two models had metallic reinforcement inside the joints. In addition, a constitutive law of the masonry defined from experimental results allowed to elaborate a simple model, which results were concordant with respect to the experimental results and similar to those calculated by complex models. Finally, two simplified models to evaluate the resistance of confined masonry walls by considering the failure plane on the wall diagonal were developed. One supposes the masonry failure by shear effect and the other supposes the masonry failure by induced tension. The ratio theoretical resistance vs. experimental resistance was adequate for walls built from different materials and tested under different loads, which had ratio Height/Length ranging from 0.74 to 1.26; Cette recherche propose des méthodes d’amélioration de résistance et d’évaluation du comportement de murs en maçonnerie confinée construits en briques solides d’argile cuite. Ces éléments sont largement utilisés dans la construction des bâtiments à l’État du Guerrero (Mexique) lesquels doivent résister charges séismiques importantes. Ainsi, un programme expérimental a été développé pour évaluer les propriétés mécaniques des briques et de la maçonnerie, qui sont nécessaires dans la conception et analyse des constructions. Pour augmenter la résistance de la maçonnerie et compenser la variabilité de la résistance à la compression des briques, un mortier à haute résistance et un renfort métallique dans les joints ont été utilisés. Certaines propriétés mécaniques sont égales à celles communément citées, cependant, les autres ont des valeurs deux fois plus grandes. Dans cette région du pays, les trois premiers tests de murs à échelle réelle construits en briques solides d’argile cuite ont été réalisés sous charge latérale alternée afin d'évaluer son comportement. Un renfort métallique et une couche du mortier ont été placés dans les surfaces de deux murs. Ceux-ci ont présenté un bon comportement et le renfort a eu un comportement structural adéquat. Avec les données expérimentales, plusieurs modèles numériques de panneaux et de murs ont été mis au point afin de reproduire l'enveloppe de résistance et le mode de défaillance. Ces modèles ont également évalué l'influence des propriétés mécaniques des briques et des joints sur le comportement global des spécimens. Aussi, un renfort métallique a été placé à l’intérieure des joints dans deux modèles. D'un autre côté, à partir de résultats expérimentaux obtenus et cités, une loi de comportement de la maçonnerie a été définie pour construire un modèle simple qui donne des résultats concordants à la fois avec les résultats expérimentaux et ceux obtenus par la méthode des éléments finis. Finalement, deux modèles simplifiés ont été proposés afin d’évaluer la résistance de murs en maçonnerie en supposant que le plan de rupture est suivant la diagonale du mur. L'un suppose la rupture de la maçonnerie par effet de cisaillement tandis que l'autre suppose la rupture par effet de tension induite. Le ratio entre résistance théorique et résistance expérimentale a été acceptable pour 27 murs faits de matériaux différents et testés sous différents types de chargement où le ratio hauteur sur longueur varie entre 0,7 et 1,26
- Published
- 2009
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