Search results for "Retrofitting"
showing 10 items of 58 documents
Evaluation of infilled frames: an updated in-plane-stiffness macro-model considering the effects of vertical loads
2015
The influence of masonry infills on the in-plane behaviour of RC framed structures is a central topic in the seismic evaluation and retrofitting of existing buildings. Many models in the literature use an equivalent strut member in order to represent the infill but, among the parameters influencing the equivalent strut behaviour, the effect of vertical loads acting on the frames is recognized but not quantified. Nevertheless a vertical load causes a non-negligible variation in the in-plane behaviour of infilled frames by influencing the effective volume of the infill. This results in a change in the stiffness and strength of the system. This paper presents an equivalent diagonal pin-jointed…
Frictional effects in structural behavior of no-end-connected steel-jacketed RC columns: Experimental results and new approaches to model numerical a…
2017
Steel jacketing of reinforced concrete (RC) columns is a common retrofitting technique used to restore bearing and deformation capacity of buildings presenting structural deficiencies. For practical reasons, steel angles are in several cases arranged leaving a gap with the end beams or slabs. Despite this disconnection, the angles are still able to support a non-negligible portion of load because of the frictional forces developed along the column-angle contact interface. In these cases, the definition of computational numerical and analytical models for the assessment of reinforced cross sections becomes more complex and must be handled with care. The actual load-carrying capacity of the a…
Steel based retrofitting interventions for existing masonry walls: a comparative numerical investigation
2021
Masonry buildings constitute a significant portion of the architectural heritage all over the world, also in regions affected by a high seismic hazard. Since this constructional material is character-ized by lack of tensile strength, as well as small deformation capacity, masonry structures could result hugely damaged if shaken by seismic forces. In order to avoid collapses and reduce struc-tural damage, innovative retrofitting interventions are necessary to improve the seismic behavior of masonry structures. In this context, steel-based techniques could be considered among the most suitable solutions. In fact, by using such a high-performant material, additional strength and ductility may …
Effects of corrosion on a steel bowstring bridge in marine environment: A case-study of assessment and retrofit
2021
The case-study of a steel bowstring bridge set in a marine environment and highly damaged by corrosion is presented. The bridge was built in 2004 and was repainted for corrosion protection in 2010. Despite the recent construction and the maintenance interventions, many structural elements like hangers are highly damaged by corrosion with decreasing performance in terms of serviceability and ultimate limit states. A deep investigation was carried out in order to assess the bridge and to establish the necessary retrofit actions to be carried out in the near future. In-situ tests reveal the reduced performance of the original steel in terms of strength and corrosion protection, together with t…
Assessment of seismic resistance of masonry structures including boundary conditions
2002
The paper is devoted to the investigation of seismic response of the masonry structure and describes experiences with modelling of boundary conditions during the test of large heavy model on 6DOF shaking table. The main aim of the research was how to increase dynamic resistance capacity of old masonry buildings including the medium and strong seismic effects. The results of theoretical and numerical analyses are compared including initial forecasting calculations made before any test started. The emphasis is given to the boundary conditions reached during the excitation of the large masonry model via shaking table. Strengthening and retrofitting procedures and their effects are discussed wh…
The Financial Costs in Energy Efficient District. Alternative Scenarios from the Demo Sites of the CITyFiED Program
2021
The European Union’s environmental policies actively promote the transition to a low-carbon society and to sustainable energy systems that improve people’s quality of life and do not negatively impact the natural environment. To achieve these goals, the European Union funded several programs to pilot energy efficiency measures for buildings and districts and, lately, launched the European Green Deal. The results of these experimentations have shown that often the economic feasibility of retrofitting interventions is not achieved without public grants. This contribution aims to analyze the influence of financial parameters on the profitability of projects of energy efficient districts. The s…
Effect of steel collars on the seismic behaviour of axially-cracked historical stone columns
2014
Granite and heavy stone circular columns could often be found in the cultural heritage among ancient churches and historical buildings in all the Mediterranean area. Their good strength properties allow them to carry big load values, while their bright colours and aesthetical characteristics were used by a lot of architects in the past to achieve structural solutions with great visual impact.Though such materials have great compressive strength values, environmental effects, especially long term effects, can damage the structural members, by cracking them. In this way the slenderness of the column increases, and the presence of an imposed ground motion can be very dangerous, since the colum…
Robot Retrofitting by Using LinuxCNC Complemented with Arduino/RaspberryPI
2020
The use of robots for any manufacturing process is present in almost every industry nowadays. Nevertheless, automating the manufacturing process has always been a challenge for every one of them due to costs and complexity of adding this kind of automation. Acquiring robotic equipment in a concentrated market where the vendors have locked-in their clients can be expensive. In addition to this, the development of intern-factory made solutions has a very steep learning curve and it is not easily achievable. Due to these barriers small and medium size players can’t easily jump into this revolution.
Excessive Deflection in Long-Span Timber Beams of a Historical Building in the South of Italy: Analysis and Retrofitting Design
2020
AbstractIn 2018, under service conditions, excessive deflections were observed in the long-span timber beams of the first floor of the former Sant’Elisabetta Monastery in Palermo (Italy). The build...
Structural Analysis, Retrofitting Design, and In Situ Control of Permanently Damaged Long-Span Timber Beams of a Historical Building in the South of …
2020
AbstractIn 2018, under service conditions, excessive deflections were observed in the long-span timber beams of the first floor of the former Saint Elisabeth Monastery in Palermo (Italy). The build...