scholarly journals Integrated Seismic and Energy Retrofitting System for Masonry Walls Using Textile-Reinforced Mortars Combined with Thermal Insulation: Experimental, Analytical, and Numerical Study

2020 ◽  
Vol 4 (4) ◽  
pp. 189
Author(s):  
Kyriakos Karlos ◽  
Aristomenis Tsantilis ◽  
Thanasis Triantafillou
Keyword(s):  
Numerical Modeling ◽  
Thermal Insulation ◽  
Seismic Vulnerability ◽  
Numerical Study ◽  
Masonry Walls ◽  
Test Results ◽  
Out Of Plane ◽  
Innovative System ◽  
Textile Reinforced Mortar ◽  
Good Agreement

Taking into consideration the seismic vulnerability of older buildings and the increasing need for reducing their carbon footprint and energy consumption, the application of an innovative system is investigated; the system is based on the use of textile-reinforced mortar (TRM) and thermal insulation as a means of combined seismic and energy retrofitting of existing masonry walls. Medium-scale tests were carried out on masonry walls subjected to out-of-plane cyclic loading. The following parameters were investigated experimentally: placement of the TRM in a sandwich form (over and under the insulation) or outside the insulation, one-sided or two-sided TRM jacketing and/or insulation, and the displacement amplitude of the loading cycles. A simple analytical method is developed and found in good agreement with the test results. Additionally, numerical modeling is carried out and also found in good agreement with the test results. From the results obtained in this study, the authors believe that TRM jacketing may be combined effectively with thermal insulation, increasing the overall strength and energy efficiency of the masonry panels in buildings.

scholarly journals Innovative Integrated Seismic and Energy Retrofitting System for Masonry Walls using Textile Reinforced Mortars Combined with Thermal Insulation: Experimental, Analytical and Numerical Study

2020 ◽  
Author(s):  
Kyriakos Karlos ◽  
Aristomenis Tsantilis ◽  
Thanasis Triantafillou
Keyword(s):  
Energy Efficiency ◽  
Numerical Modeling ◽  
Thermal Insulation ◽  
Seismic Vulnerability ◽  
Numerical Study ◽  
Masonry Walls ◽  
Test Results ◽  
Out Of Plane ◽  
Innovative System ◽  
Good Agreement

Taking into consideration the seismic vulnerability of older buildings and the increasing need for reducing their carbon footprint and energy consumption, the application of an innovative system is investigated; the system is based on the use of textile reinforced mortars (TRM) and thermal insulation as a means of combined seismic and energy retrofitting of existing masonry walls. Medium scale tests were carried out on masonry walls subjected to out-of-plane cyclic loading. The following parameters were investigated experimentally: one-sided versus two-sided insulation and/or TRM jacketing, placement of the TRM outside the insulation or in a sandwich form (over and under the insulation), as well as the displacement amplitude of the loading cycles. A simple analytical method is developed and is found in good agreement with test results. Additionally, numerical modeling is carried out and is also found in good agreement with test results. From the results obtained in this study the authors believe that TRM jacketing may be combined effectively with thermal insulation, increasing the overall strength and energy efficiency of the masonry panels in buildings.

Numerical Modeling and Parametric Analysis of Multiplanar CHS KT-Joints with K-Plane Overlap and Out-of-Plane Gap

2011 ◽  
Vol 94-96 ◽  
pp. 575-582
Author(s):  
Jian Dong Sun ◽  
Jun Li Lv ◽  
Tao Du ◽  
Yang Xian Li
Keyword(s):  
Numerical Modeling ◽  
Parametric Analysis ◽  
Element Model ◽  
Ultimate Capacity ◽  
Dimensional Parameter ◽  
International Convention ◽  
Out Of Plane ◽  
Dimensional Parameters ◽  
Test Result ◽  
Good Agreement

A finite element model simulating the experiment on multiplanar unstiffened CHS KT joints with K-plane overlapped and out-of-plane not (KT-IPOv joints), with the background of Suzhou International Convention & Exhibition Center, was advanced and validated by comparing failure mode and the ultimate capacity with experimental results, which is shown to be in good agreement with the test result. Using this model, the effect of non-dimensional parameters on ultimate capacity of KT-IPOv joints were studied, and resistance comparison between multiplanar KT-IPOv joints and uniplanar overlapped K-joints was carried out. The results of FE parametric Analysis conclude that multiplanar parameter ζ t, τT and βT have not significant influence on the ultimate strength; the effect of non-dimensional parameter βK, τK, γ, Ov on the resistance of multiplanar KT-IPOv joints has the same as that of uniplanar overlapped K-joints; the strength of multiplanar KT-IPOv joints have been not significantly influenced by the configuration with the brace inside T-plane which it is not subjected to force; it is suitable and feasiable that ultimate capacities of KT-IPOv joints predicted by formula of uniplanar K-joints.

Rehabilitation of Masonry Buildings with Fibre Reinforced Mortar: Practical Design Considerations Concerning Seismic Resistance

2021 ◽  
Vol 898 ◽  
pp. 1-7
Author(s):  
Ingrid Boem ◽  
Natalino Gattesco
Keyword(s):  
Seismic Vulnerability ◽  
Seismic Resistance ◽  
Masonry Walls ◽  
Masonry Buildings ◽  
Historic Masonry ◽  
Collapse Mode ◽  
Practical Design ◽  
Out Of Plane ◽  
Historical Masonry

Historic masonry buildings experience a high seismic vulnerability: innovative intervention strategies for strengthening, based on the use of fibre-based composite materials are gradually spreading. In particular, the coupling of fibre-based materials with mortar layers (Fibre Reinforced Mortar technique - FRM) evidenced a good chemical and mechanical compatibility with the historical masonry and proved to be effective for the enhancement of both in-plane and out-of-plane performances of masonry, contrasting the opening of cracks and improving both resistance and ductility. The resistant mechanisms that arise in FRM strengthened masonry walls subjected to in-plane horizontal actions are analyzed in the paper and a practical design approach to evaluate their performances is illustrated, evidencing the dominant collapse mode at the varying of the masonry characteristics. Some masonry walls are analyzed numerically and analytically, as “case study”.

Out-of-Plane Dynamic Stability of Unreinforced Masonry Walls in One-Way Bending: Shake Table Testing

2016 ◽  
Vol 32 (3) ◽  
pp. 1675-1697 ◽  
Author(s):  
Osmar Penner ◽  
Kenneth J. Elwood
Keyword(s):  
Ground Motion ◽  
Companion Paper ◽  
Unreinforced Masonry ◽  
Masonry Walls ◽  
Shake Table ◽  
Brick Wall ◽  
Test Results ◽  
Ground Motion Variability ◽  
Out Of Plane ◽  
Assessment Guidelines

Given sufficient anchorage to the diaphragms, an unreinforced masonry (URM) wall subjected to out-of-plane inertial forces will likely develop a horizontal crack at an intermediate height about which the wall will rock as semirigid bodies. The effect of wall slenderness on out-of-plane stability has been demonstrated in past studies, but treatment of the effects of diaphragm flexibility and ground motion variability has been limited. This paper presents an experimental study examining the out-of-plane stability under seismic loading of URM walls connected to flexible diaphragms. Five full-scale unreinforced solid clay brick wall specimens spanning one story were subjected to earthquake ground motions using a shake table. The top and bottom of the walls were independently connected to the shake table through coil springs, simulating the flexibility of diaphragms. Variables examined experimentally included diaphragm stiffness and wall height. Both the amount of rocking observed as well as the ground motion scale causing collapse varied significantly with changes in the diaphragm properties. The test results provided data used for validation of a rigid-body rocking model, enabling an extensive parametric study on wall stability and the development of new assessment guidelines in a companion paper.

Behavior of Confined Masonry Walls with Openings under In-Plane and Out-of-Plane Loads

2018 ◽  
Vol 34 (2) ◽  
pp. 817-841 ◽  
Author(s):  
Vaibhav Singhal ◽  
Durgesh C. Rai
Keyword(s):  
Structural Integrity ◽  
Solid Wall ◽  
Ground Motions ◽  
Masonry Walls ◽  
Load Carrying Capacity ◽  
Test Results ◽  
Severe Damage ◽  
Confined Masonry ◽  
Load Carrying ◽  
Out Of Plane

Six half-scaled wall panels were tested to investigate the effect of openings on their load-carrying capacity; these walls were subjected to a sequence of slow cyclic in-plane drifts and shake table–generated out-of-plane ground motions. Two specimens were masonry-infilled frames with and without openings. The other four specimens were confined-masonry (CM) walls, with one solid wall and three walls with openings bounded by reinforced-concrete (RC) confining elements on all sides. The infill walls demonstrated higher risk of out-of-plane collapse, whereas the CM walls maintained structural integrity and out-of-plane stability. The test results clearly indicate the necessity of confinement all around the openings for good seismic performance. The confining scheme with no continuous horizontal bands was ineffective in confining wall piers at large drifts, and piers remain vulnerable to out-of-plane collapse due to severe damage. However, the wall with continuous horizontal bands at the lintel and sill levels was not only able to compensate for deficiencies in strength due to the presence of openings, but also achieved a better overall behavior due to more distributed damage and greater ductility.

Out-of-plane seismic retrofitting of masonry walls with Textile Reinforced Mortar composites

2019 ◽  
Vol 17 (11) ◽  
pp. 6265-6300 ◽  
Author(s):  
Stefano De Santis ◽  
Gerardo De Canio ◽  
Gianmarco de Felice ◽  
Pietro Meriggi ◽  
Ivan Roselli
Keyword(s):  
Seismic Retrofitting ◽  
Masonry Walls ◽  
Out Of Plane ◽  
Textile Reinforced Mortar

Experimental and Numerical Study of a Fixturing System for Complex Geometry and Low Stiffness Components

2016 ◽  
Vol 139 (4) ◽  
Author(s):  
Andrés A. Gameros ◽  
Dragos Axinte ◽  
Héctor R. Siller ◽  
Stewart Lowth ◽  
Peter Winton
Keyword(s):  
Complex Geometry ◽  
Numerical Study ◽  
Point Of View ◽  
Average Error ◽  
Fe Model ◽  
Innovative System ◽  
Low Stiffness ◽  
Feasible Solutions ◽  
Good Agreement ◽  
Complex Components

The production of freeform components is challenging, not only from the point of view of process optimization but also when it comes to the selection and design of the fixturing systems. Currently, most commercially available fixturing systems are difficult to conform to geometrically complex components; while the systems that manage to provide industrially feasible solutions (such as encapsulation techniques) present several limitations (e.g., high complexity, limited reliability, and risk of elastic deformation of the part). In this context, the present work proposes a simple, yet efficient, concept of a fixture capable of holding complex components through the use of compliant/deformable diaphragm elements. The fundaments of this innovative system (i.e., freeform diaphragm-based fixturing system) have been simulated through an experimentally validated finite-element (FE) model, with results showing a good agreement between numerical and measured data (displacement average error ϵav = 4.04%). The main interactions of the system with a workpiece (e.g., contact area and clamping force) have been numerically and experimentally studied, confirming the system's capacity to generate distributed clamping forces in excess of 1000 N. Based on the modeling activities, an advanced prototype for holding a “generic” freeform component was developed. Using this prototype, a repeatability study then showed the capacity of the system to deterministically position and hold complex geometries. Finally, the proposed fixturing system was thoroughly evaluated under demanding machining conditions (i.e., grinding), and the results showed the ability of the fixture to maintain small part displacement (dx < 10 μm) when high cutting forces are applied (Max. FR = 1021.24 N). Design limitations were observed during the grinding experiments, and the lineaments are presented in order to develop improved further prototypes. Overall, the proposed fixturing approach proved to be a novel and attractive industrial solution for the challenges of locating/holding complex components during manufacture.

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