Seismic retrofitting Research Papers - Academia.edu (original) (raw)

The paper describes an experimental investigation of a new earthquake damper, the yielding shear panel device (YSPD), for civil structures. It utilizes energy dissipation through plastic shear deformation of a thin diaphragm steel plate welded inside a square hollow section (SHS). Its performance is verified by nineteen monotonic and cyclic tests. Experiments showed that certain specimens exhibited stable behavior and were capable of dissipating a significant amount of energy. The performance is influenced by the diaphragm plate slenderness and by the in-plane rigidity of the surrounding SHS. Slender plates undergo elastoplastic shear buckling and exhibit stable though slightly pinched hysteresis response. Stocky plates impose high deformation demand on the surrounding SHS that hinders their cyclic performance. The equivalent viscous damping offered by the test specimens, on their own, and the cumulative energy dissipation are quantified. Fabrication, implementation and replacement of the damper proved to be easy and inexpensive. The YSPD offers a potentially viable alternative for seismic retrofitting of existing frame structures.

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- Civil Engineering, Energy Dissipation, Cumulant, Shear deformation
- by Murat Dicleli
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- Civil Engineering, Modernization, Structures and Fire Engineering, Modal Analysis

In many countries, buildings are usually made of unreinforced clay masonry walls, especially in Colombia. These constructions have
low resistance and ductility, and are very vulnerable to seismic events, due to their low capacity of energy dissipation. This paper
reports the results obtained from a research project that evaluates the behavior of reinforced masonry walls under lateral loads. The
reinforcement was made using Carbon Fiber Reinforced Polymers (CFRP). In the test program, eight (8) clay masonry walls were built
using hollow brick. Four (4) of them were 1,23 m long and 1,90 m high and the remaining four (4) were 2,47 m long and 1,90 m
high. Four (4) walls were tested with a static lateral load and four (4) with a cyclic lateral load in its plane. Results revealed that the
presence of the reinforcement material significantly increased the ultimate load and deformation capacity, provided that the material
has a suitable anchoring system.

- by Ingeniería e Investigación and +2
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- Fiber Reinforced Polymers, Unreinforced masonry., Seismic retrofitting, Lateral Loads
- by Shubash Sah Godh
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- Seismic retrofitting
- by Abhik Adak
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- Seismic retrofitting
- by Camillo Nuti
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- Seismic retrofitting
- by mahmoud reza maheri
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- Civil Engineering, Typology, Modernization, Structures and Fire Engineering
- by Lotfi Guizani
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- Civil Engineering, Earthquake Engineering, System Design, Standardization
- by Jorge Salazar
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- Engineering, Structural Engineering, Base Isolation, Case Study
- by Hasan OZKAYNAK
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- Civil Engineering, Materials Science, Structural Engineering, Seismic Retrofit

The mechanical characteristics of infill walls retrofitted with carbon fiber reinforced polymer (CFRP) sheets are really important for the realistic prediction of seismic performance of the vulnerable reinforced concrete (RC) frames retrofitted through CFRP strengthened infill walls. In this study, 36 hollow brick wall specimens were tested either under uniaxial compression or diagonal tension before and after retrofitting externally with CFRP sheets. The test parameters are the dimensions of the walls, the orientation of holes of bricks, the type of mortar, the amount of CFRP sheets and the details of strengthening application. At the end of the tests, a significant contribution of CFRP sheets on the mechanical characteristics of hollow brick walls was observed in terms of several important structural design parameters such as Young and shears moduli, axial and shears strengths as well as the deformation capacity. Finally, the strength and deformability characteristics of the walls and frames retrofitted with CFRP sheets were predicted analytically. The predictions were in good agreement with the experimental data.► The characteristics of infill walls retrofitted with CFRP sheets determined from uniaxialcompressionand diagonal tension tests. ► The wall dimensions, the orientation of holes of bricks, the type of mortar, the amount of CFRP sheets are the test parameters. ► Significant contribution of CFRP sheets on the mechanical characteristics of hollow brick walls was observed. ► The strength and deformation capacities of the walls and RC frames retrofitted with CFRP sheets were good estimated analytically.

- by Hasan OZKAYNAK and +1
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- Civil Engineering, Seismic Retrofit, Structural Design, Building

This paper reviews the results of some recent works conducted by the author on new methods of retrofitting the RC frames. On the local retrofit of RC members, it includes the work on the application of a new high performance fibre-reinforced cementitious composite material. The composite can be applied either as a wet mix to the desired thickness or attached as precast sheets or strips to the face of the member using a suitable epoxy adhesive. The suitability of this technique of member retrofit to enhance the strength and ductility of the retrofitted member compared with other methods of local retrofit, such as steel plates and FRP laminates, is discussed. Other works reviewed in this paper include those carried out recently on global retrofit of RC frames using direct internal steel bracing. Results of inelastic pushover tests on scaled models of ductile RC frames, directly braced by steel X and knee braces are presented which indicate that such bracings can increase the yield and...

- by Mahmoud Maheri
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- Engineering, Pushover Analysis, Composite Material, Bracing

Santa Maria of Montedecoro is a sacral complex located in Maddaloni, in the south of Italy, and is one of the most important historical monuments of the city. Built in the sixteenth century, the monastic organism consists of an aggregate structure, including the church dedicated to the Virgin Mary, the bell tower which is set back from the church, the sacristy, the parsonage. This paper concerns the analysis of all the degradation phenomena identified in the complex, due to both its deterioration state and structural damage. Particular attention is placed on the bell tower that shows different degradation of the surfaces, with large erosions and fallen plasters. The masonry structure, notably compromised, shows several cracks due to the rotation of the tower towards the street. Because of such damage phenomena, a preliminary investigative research was performed to understand the effective conservation state of the Church and its appurtenances. The obtained diagnostic survey data confirm the hypotheses advanced in the cognitive phase and have provided all the necessary elements for the restoration and retrofitting design. This paper presents the restoration design and the results of the seismic analyses carried out on the bell tower.

- by IEREK press
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- Conservation, Restoration, Church, Consolidation

- by EMRE YILMAZ
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- Civil Engineering, Seismic Retrofit, Structural Design, Building

This study examines the performance-based design of structure that is increasing commonly in earthquake resistance design. to ensure any structure possess earthquake resistant design, certain minimum performance objective is desired at different level of seismic excitation. With the help of some devices, Low to medium rise buildings are performing well for the seismic actions. In the present work, originally deficient RC frame is analyzed with static analysis and after this static non-linear analysis is performed in which suitable energy dissipation devices are installed sequentially. first analyzed with Viscous fluid Damper then Lead-rubber isolator is used has designed as per performance-based design criteria of G+6 RC frame building. These models are analyzed for important residential use and located at seismic zone IV. Linear static and nonlinear static methods are used to analyze the structure with help of CSI ETABSv18 software. Results which are discussed is minimum performance level, story drift, performance point and performance objective. After analysis of results, structure which is installed with Led-rubber bearing isolator is performed well during an earthquake and satisfy with desired minimum performance level. In case of viscous fluid damper, it is not satisfactory to achieve desired minimum performance up to this extent it helps to reduce floor acceleration. I.

- by IJRASET Publication
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- Structural Engineering, Robot Rc, Framed Structure, Seismic retrofitting

The strengthening technique based on the application of multi-directional laminates of CFRP (MDL-CFRP) simultaneously glued and anchored to the surface of the elements to be strengthened has been recently proposed. This technique was designated Mechanically Fastened and Externally Bonded Reinforcement (MF-EBR) and combines the fasteners from the MF-FRP technique with the externally glued properties from the EBR. With the aim of assessing the potentialities of this technique for seismic retrofitting, three interior RC beam ...

- by Julienne trindade melo
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- Engineering, Materials Science, Advanced Materials, AMR
- by Azadeh Parvin
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- Polymers, Durability, Seismic retrofitting
- by S. Casolo
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- Civil Engineering, Structural Engineering, NDT, Seismic retrofitting