Seismic analysis of Santa Maria del Mar church in Barcelona

Santa Maria del Mar és una joia arquitectònica construïda en només 50 anys en un estil gòtic pur i sobri. Acabada a finals del segle XIV, l’edifici inclou innovacions estructurals molt interessants compartides només, entre totes les construccions gòtiques, amb les catedrals de Barcelona i Mallorca. Aquest edifici es caracteritza per tenir 3 naus i no tenir creuer, creant un espai interior molt ampli gràcies a uns pilars molt esvelts i unes voltes amb grans llums.En aquest treball s’ha dut a terme una anàlisi estructural més acurada, aprofitant noves dades més precises sobre la morfologia de l’estructura. S’ha utilitzat un model de dany de tracció – compressió per a realitzar una Anàlisi per Elements Finits en la crugia tipus de l’edifici. Basat en la teoria del dany, té en compte el comportament diferenciat de l’obra de fàbrica a tracció i compressió

Comprehensive review of the structural behaviour and numerical modelling of recycled aggregate concrete-filled steel tubes

This paper summarises current research findings related to the behaviour and simulation of a relatively new type of structural component: recycled aggregate concrete-filled steel tube columns (RACFST). The first part of the paper presents a review of the latest experimental campaigns on RACFST columns subjected to a variety of loading conditions. For each of loading condition, highlight observations about the behaviour of RACFST columns are presented. The second part of the paper provides a summary of numerical modelling approaches developed for simulating the structural behaviour of RACFST columns. Special attention is paid to the selection and calibration of material models for recycled aggregate concrete. Finally, directions for future investigations in this area are outlined and discussed. The review will benefit researchers and professionals seeking to gain an indepth understanding of the behaviour of RACFST columns, and fills a gap in existing literature regarding a number of practical issues related to the numerical modelling of these components

Probabilistic Evaluation of Post-Earthquake Functional Recovery of a Seismically Isolated RC Building

All earthquakes throughout history have taught us that damage to non-structural elements and content has serious repercussions on the direct economic cost of damage and functionality. In essential buildings such as hospitals, rapid functional recovery is essential to safeguard the lives of the occupants and the injured who arrive after the earthquake. This study presents the detailed evaluation of the functional recovery of a RC seismically isolated 8 story hospital building located in an area of high seismicity. The study is carried out using the probabilistic analytical framework F-Rec, which has been recently proposed in the literature for the evaluation of the functional recovery of buildings after an earthquake. This framework complements the FEMA P-58 performance evaluation methodology allowing a complete and detailed evaluation of post-earthquake functionality, duration of damage and the path of functional recovery, considering structural and non-structural elements and content. In this study, a non-linear model of the building is created in OpenSees and the seismic response is studied for three hazard scenarios, Service Level Earthquake (SLE), Design Based Earthquake (DBE) and Maximum Considered Earthquake (MCE). Based on the results of the non-linear analyses, the damage losses are calculated using the FEMA P-58 tool, while the building recovery process is evaluated using the F-Rec framework. The efficient functional recovery time and route are analyzed for each scenario. The results show that the F-Rec framework is a viable tool for the evaluation of the post-earthquake functionality of isolated hospital buildings, but that there is a need to develop specific fragility and recovery curves for medical equipment.Peer ReviewedPostprint (published version

3D strut-and-tie modeling for design of drilled shaft footings

Project performed in cooperation with the Texas Department of Transportation and the Federal Highway Administration at the Center for Transportation Research of The University of Texas at Austin.A comprehensive study was conducted to characterize the structural response and develop design guidelines for drilled shaft footings. The study included large-scale testing and numerical analyses of footing specimens subjected to various loading conditions. A database of 35 drilled shaft footings constructed in Texas by TxDOT was established and analyzed for designing test specimens. A total of 19 large-scale specimens were designed and tested to study various design parameters and loading scenarios including vertical compression and uniaxial bending. A series of numerical analyses employing experimentally-verified models were also performed to account for the effect of additional design parameters that could not be covered in the experimental program. Based on the data and insights obtained from the experimental and numerical studies, 3D strut-and-tie modeling guidelines for drilled shaft footings are proposed by refining current provisions for 2D strut-and-tie models in AASHTO LRFD (2020). The new guidelines include the definition of the 3D nodal geometry at bearing faces, refinements for strength modification factors, critical section definitions for development of horizontal and vertical ties, and recommendations for bottom mat reinforcement configuration. Project findings have indicated that the proposed recommendations improve the accuracy of the ultimate strength predictions for a database including drilled shaft footing tests from the literature and the current study, without generating unconservative or overly conservative predictions. This represents an improvement of the accuracy achieved using the recommendations of TxDOT Project 5-5253-01. Lastly, a design example of a drilled shaft footing subjected to various loading scenarios is provided.Preprin

Evaluation of Seamless Bridges

0-7011The research study included experimental testing and numerical modeling to obtain and develop much needed experimental data and analytical tools to study the performance of seamless systems, identify design issues, and propose design guidelines for the U.S. practice

Analytical model for pullout and splitting failures in bar anchorages and laps

This paper presents a unified analytical method to predict the slip and tensile strength capacity of both straight anchorages and lap splices. Closed-form solutions of the slip at the loaded end of an anchorage or lap splice are derived based on a set of simplified bond stress distributions applicable for different geometrical and loading conditions. The model assumes a linear bond stress distribution along the elastic portion of the anchorage/splice, and a constant bond resistance within the region where the bar has yielded in tension. Closed-form solutions of the ultimate strength capacity of the anchorage/splice are also obtained by combining the proposed model with a simple bond failure criteria and the local bond strength specified in the 2010 Model Code. The proposed formulation is shown to predict with overall good accuracy the slip response of bar anchorage tests reported in the literature, including pullout failures, and the lap-splice strength of 457 test specimens from the ACI 408 database.Postprint (published version

Modeling bar slip and pullout capacity of straight anchorages

This paper presents an analytical method to predict the bar slip and pullout capacity of straight bars embedded in well-confined concrete, such as column bars extended into a footing or cap beam. Closed-form solutions of the slip at the loaded end of the anchorage length and the pullout strength of the anchorage are derived based on a set of a priori bond stress distributions for elastic and plastic loading situations. The model assumes a linear distribution of bond stresses along the elastic portion of the anchorage length, and a constant bond resistance within the region where the bar has yielded in tension. For relatively short embedment lengths, the slip at the unloaded end is also considered. The accuracy of the model in predicting the loaded-end slip, the strains along the embedment length, and the bar pullout capacity has been verified with experimental data. The model provides an accurate representation of the global response of straight anchorages up to the ultimate tensile strength or the pullout failure of the bar. It also results in a sufficiently accurate representation of the strain distributions obtained experimentally in pullout tests on bars with different embedment lengths.Postprint (published version