Pedro Silva Delgado

• PhD
• Professor (Adjunct) at Polytechnic Institute of Viana do Castelo

Reinforced concrete (RC) hollow section piers have been the subject of several studies in the recent past, from which one important drawn conclusion is the significant influence of shear effects on these piers behaviour, particularly under cyclic loading. In that framework, tests were carried out at Laboratory of Earthquake and Structural Engineeri...

Hollow bridge piers, particularly those built before the seventies, often have insufficient shear capacity due to inadequate transverse reinforcement details. Therefore, special attention must be given to this very important aspect when reinforced concrete (RC) piers with hollow sections are analysed and retrofitted. This paper covers the experimen...

The methods presented in chapter 3 are applied here to specific case-studies, involving bridges with different length and configuration. The chapter starts with a critical discussion of the basic parameters that influence the applicability of pushover methods. Then, a number of case-studies are presented in a rather uniform and detailed way; they w...

This article addresses numerical simulations of experimentally tested RC hollow-section piers prone to shear problems under cyclic loading. Detailed nonlinear modeling was applied with 3D FEM discretization using a damage model for concrete and a cyclic behavior model for steel bars represented by uniaxial elements Analyses were supported by parame...

Shear effects are often a very important issue on the seismic behaviour of piers, particularly for hollow section bridge piers. In fact, for this type of piers the cyclic response is similar to that of a structural wall in which both the transverse reinforcement ratio and the detailing can play an important role on its performance, even likely to b...

A regular evaluation of the applied wood condition is important since the initial years of service, when some signs of damage could start to appear, to optimize the treatments during their lifetime and reduce maintenance costs. This study presents a methodology for inspecting and classifying damages in wood relying on visual inspection. The present...

The importance of the sustainability of wood buildings is increasing. The renewed attention highlights the need to assess the wood deterioration accurately, in the initial years of service, to optimize treatment during its lifetime and reduce maintenance costs. This study presents a methodology for inspecting and classifying damage of wood in servi...

In the context of inspection and maintenance actions for beach walkways in the North of Portugal, some samples of wood used in their construction were collected – the Pinus sylvestris wood, widely applied in the country. The sustainability of the beach walkways over natural coastal areas is very dependent on their material durability. One of the ma...

Seismic hazard assessment in several sites worldwide depends on two or more seismic sources. Many countries affected by subduction zones have strong motions earthquakes originated in at least two important seismic sources. In Mexico, interplate earthquakes (subduction process) have epicenters located in the Pacific coast with hypocenter depths less...

Overstrength factors in bridges reported in various studies show great diversity that depends on the type of bridges selected and the set of seismic records used in the analyses. Particularly in Mexico, there are no previous studies that evaluate the bridges’ overstrength. This study determines overstrength factors in medium-length reinforced concr...

Mexico highway network has more than 14,000 bridges. Most of them are reinforced concrete (RC) structures. The bridges design process incorporates the use of an overstrength factor that is not justified and has received little attention in published works. Mexican regulations allow using an overstrength factor for buildings in the range of 2–3, to...

Important investments have been made worldwide in the modernization and construction of railway lines. Plans for new constructions have also been laid out. Recently, precast concrete has been widely employed in the construction of railway bridges and viaducts. Several precast solutions have been applied, namely: I-shaped or U-shaped precast girders...

This study involves the applicability of a simplified modeling technique to simple-span slab-girder skewed bridges for dynamic analysis, based on grillage modeling strategies. To evaluate the applicability of this technique, skew angles ranging from 0° to 60° are studied. The ability to capture vibration modes of grillage models is compared with th...

During past seismic events several cases of concrete bridges with poor structural behaviour and severe damage were reported. In this chapter, common damage patterns in RC bridges are illustrated, with reference to several previous studies about the seismic performance of bridge components. The focus of the chapter is on pier behaviour, wherein dama...

The out-of-plane (OOP) performance of infill masonry walls subjected to earthquakes is a topic of growing importance due to the significant number of collapses observed through the recent earthquakes. Nowadays is recognized by the scientific community the influence of these elements in the structural response of reinforced concrete structures subje...

Over the last years, there has been increasing interest on experimental testing to support better understanding of structural behaviour under earthquake loading, with emphasis on numerical model calibration, development of efficient techniques for seismic protection and/or resilience improvement of structures. A significant number of experimental s...

Durante os últimos anos tem-se observado um crescimento significativo do volume de testes experimentais realizados para suporte de um melhor entendimento do comportamento de estruturas/elementos estruturais quando sujeitos a ações sísmicas, com enfase na calibração de modelos numéricos, desenvolvimento de técnicas de reforço/reparação, entre outros...

The main objective of this paper is to evaluate the cyclic behavior of RC hollow piers, with and without with CFRP retrofit, by comparison of experimental tests results with structural numerical modeling. The retrofit techniques aim to increase the shear strength and the ductility capacity through the establishment of principles and strategies appl...

The seismic damages of reinforced concrete bridges in recent events show that many of them have an inadequate behavior and safety. Therefore, is important to accurately define bridge safety assessment and hence evaluate the accuracy of the analytical methodologies for seismic response of bridges. The main objective of this paper is to present sever...

The main purpose of this chapter is to present numerical methodologies with different complexities in order to simulate the seismic response of bridges and then use the results for the safety assessment with one probabilistic approach. The numerical simulations are carried out using three different methodologies: (i) plastic hinge model, (ii) fiber...

The main objective of this paper is to evaluate the cyclic behaviour of RC hollow piers, with and without with CFRP retrofit, by comparison of experimental tests results with structural numerical modelling. O objetivo deste artigo é avaliar o comportamento cíclico de pilares de betão armado com secções ocas, com ou sem reforço de bandas de CFRP, a...

Objectives – Experimental evaluation of seismic rehabilitation and retrofit of RC columns with CFRP. – Study of design procedures for CFRP shear retrofitting and ductility capacity improvement Conclusions-Columns were retrofitted with CFRP, according to Priestley et al.(1996), with the purpose to replace or improve the initial conditions. For soli...

Os elementos estruturais de betão armado são muitas vezes susceptíveis de ter uma inadequada resistência sísmica, devido a má pormenorização das armaduras transversais, insuficiente ductilidade nas zonas de formação de rótula plástica ou, ainda, insuficiente capacidade ao corte. Assim, justificase, uma atenção especial a esses aspectos quando se re...

Reports of seismic effects on reinforced concrete bridges, especially those built according to the codes of practice of the seventies, show that a lot of them behave poorly and have an inadequate safety assessment. Some efforts, therefore, must be made to accurately define bridge assessment and hence evaluate the need for reliable solutions to impr...

An experimental cyclic campaign of RC hollow piers has being carried out in the Laboratory for Earthquake and Structural Engineering (LESE) of the Faculty of Engineering of University of Porto (FEUP), aiming to establish, among other purposes, a strategy to retrofit RC hollow piers subjected to horizontal cyclic actions with axial load. The retrofi...

The main objective of this paper is to present a strategy of retrofit RC hollow piers subjected to horizontal cyclic actions with axial load. Mainly, the retrofit technics aim to increase the shear strength and the ductility capacity through the establishment of principles and strategies applied in an experimental cyclic campaign of RC hollow piers...

The main purpose of this paper is to present the calibration of numerical tools based on the results of a experimental cyclic behavior campaign of RC columns, carried on the Laboratory LESE - FEUP, that involved a several specimens tested as build and after reinforcement or retrofitting techniques. The numerical simulations also allowed the interpr...

The analytical tools necessary for the implementation of inelastic methods for bridges are presented. The chapter starts with available models for the bridge deck and their role in seismic assessment, addressing not only elastic modelling of the deck but also far less explored issues like the verification of deck deformation demands in cases that i...

The main objectives of this thesis deal with the study of the seismic behaviour of reinforced concrete bridges. The thesis addresses the seismic vulnerability assessment of such structures, involving the nonlinear material behaviour, and includes the experimental study of hollow section bridge piers under cyclic loading along with several retrofitt...

Research on seismic safety assessment has been the centre of great interest among the scientific community in recent years. Although the devastating impact of earthquakes on current society should be incentive enough to increase research, the development of more realistic mechanical behaviour models and the continuous enhancement of computation cap...

The main purpose of this paper is to present an experimental and numerical study concerning the influence of the transverse reinforcement details on the cyclic behavior of RC hollow bridge piers. Another strong motivation for this work relies on the fact that rectangular RC hollow piers exhibit a peculiar structural behavior, close to structural wa...

The main purpose of this paper is to present the numerical simulation of different strategies for the seismic retrofit of reinforced concrete frames, comparing the obtained solutions with the experimental results, and evaluating benefits concerning their structural behaviour under the seismic action.This work is based on the study of a RC frame, re...

The main purpose of this paper is to present an experimental and numerical study concerning retrofit techniques on cyclic behavior of RC columns. The Laboratory for Earthquake and Structural Engineering (LESE) of the Faculty of Engineering of University of Porto (FEUP) is performing an experimental campaign on RC columns representative of typical b...

This work mainly aims at a comparative study between several numerical methods for non-linear cyclic behavior simulation of reinforced concrete members, namely the continuum damage, the fiber and the concentrated plastic hinge models, in order to establish the applicability of each numerical tool. The damage model is based on 2D or 3D finite elemen...

Dissertação apresentada para obtenção do grau de Mestre em Estruturas de Engenharia, na Faculdade de Engenharia da Universidade do Porto, sob a orientação do Professor Aníbal Costa