https://hdl.handle.net/10481/24982 2026-04-21T15:01:04Z 2026-04-21T15:01:04Z Ávila Cruces, Fernando José Puertas García, María Esther Gallego Sevilla, Rafael https://hdl.handle.net/10481/87174 2024-01-24T08:14:56Z

Probabilistic reliability assessment of existing masonry buildings: The church of San Justo y Pastor Ávila Cruces, Fernando José; Puertas García, María Esther; Gallego Sevilla, Rafael There exists a large number of masonry historical buildings with a high heritage value whose preservation has to be ensured. For this purpose, it is important to establish a methodology to assess their structural reliability in the case of extraordinary load events. Particularly, the materials and construction techniques employed in this kind of buildings make them especially vulnerable in the event of an earthquake. This paper presents and discusses a probability-based reliability analysis to determine the damage on existing masonry structures subjected to seismic loads. Geometric and material data are introduced in a three-dimensional FEM model, which takes into consideration the uncertainties that exist in the material properties. The reliability of the structure is determined via the definition of a Damage Index and carrying out a Monte Carlo-type analysis. The case of study presented in this paper is the church of San Justo y Pastor located in Granada, a seismic-prone region in southern Spain.

Arto Torres, Ignacio Gallego Sevilla, Rafael Cifuentes Bulte, Hector Puertas García, María Esther Gutiérrez Carrillo, María Lourdes https://hdl.handle.net/10481/87169 2024-01-23T13:31:10Z

Fracture behavior of rammed earth in historic buildings Arto Torres, Ignacio; Gallego Sevilla, Rafael; Cifuentes Bulte, Hector; Puertas García, María Esther; Gutiérrez Carrillo, María Lourdes Rammed earth is the construction system of many heritage structures and buildings in different regions of the planet, some of which are seismically active areas. For this reason, these historic buildings can sustain structural damage or have already been subjected to stresses that have led to high levels of cracking in the rammed earth walls. Therefore, knowledge of the fracture behavior of this material is essential to assess the actual state of structural safety and the remaining mechanical capacity. The number of studies on the fracture behavior of rammed earth is limited, and even fewer studies have considered lime as a stabilizer and used traditional materials. This study measured the density, ultrasonic pulse velocity, fracture energy and tensile strength of prismatic specimens with two different soil: lime dosages and found relationships between the different parameters analyzed and the dosages used. Finally, it was verified that the fracture behavior of rammed earth can be assumed to be similar to that of mass concrete from a qualitative standpoint. For this reason, rammed earth could be considered as a quasi-brittle material that follows Hillerborg's discrete crack model. This study is part of the project ‘‘Revalorización Estructural del Patrimonio Arquitectónico de Tapial en Andalucía” (Structural Revaluation of the Rammed Earth Architectural Heritage in Andalusia), ref. A-TEP-182-UGR18, within the framework of the European Regional Development Fund Programme of Andalucía 2014-2020), and the Research Group TEP167 Solid and Structural Mechanics. The authors has received additional support from the project PREFORTI (BIA2015 69938-R) entitled ‘‘Metodología sostenible de conservación y mantenimiento de fortificaciones medievales de tierra del sudeste de la Península Ibérica. diagnóstico y prevención ante riesgos naturales y antrópicos” (”Sustainable methodology for the conservation and maintenance of mediaeval rammed-earth fortifications in the south-east of the Iberian Peninsula. Diagnosis and prevention against natural and anthropic risks”), financed by the Agencia Estatal de Investigación (Spanish National Research Agency) and the European Regional Development Fund.

Ávila Cruces, Fernando José Puertas García, María Esther Gallego Sevilla, Rafael https://hdl.handle.net/10481/87168 2024-01-23T13:23:09Z

Mechanical characterization of lime-stabilized rammed earth: Lime content and strength development Ávila Cruces, Fernando José; Puertas García, María Esther; Gallego Sevilla, Rafael Earth construction techniques, such as rammed earth, are present worldwide due to the availability of the material and its mechanical performance. Today they are also attracting attention as an environmentally friendly way of building, although additivation is usually needed. Lime stabilization is an interesting option with long tradition, well-known capacity to improve soil properties and limited environmental impact. This study evaluates the effect of increasing lime contents in the compressive strength and stiffness of rammed earth, and analyzes the strength development process of the material. Carbonation depth and ultrasonic pulse velocity are also evaluated due to their relationship with the mechanical behavior. The results show that 12% lime maximized the compressive strength and stiffness of the rammed earth material; the strength was mostly developed during the first month but needs over a hundred days to be fully developed. A good linear correlation between the ultrasonic pulse velocity and the compressive strength is observed. This research was supported by the Spanish Ministry of Universities via a doctoral grant to Fernando Ávila (FPU18/03607). The study is part of the project ‘‘Revalorización Estructural del Patrimonio Arquitectónico de Tapial en Andalucía’’ (Structural Revaluation of the Rammed Earth Architectural Heritage in Andalusia), ref. A-TEP-182-UGR18, within the framework of the European Regional Development Fund Program of Andalusia 2014–2020, and has been carried out by members of the Research Group ‘‘Solid Mechanics and Structures’’ (TEP167) at the Sustainable Engineering Structures Laboratory (SES-Lab) of the University of Granada.

Martínez Soto, Fernando Ávila Cruces, Fernando José Puertas García, María Esther Gallego Sevilla, Rafael https://hdl.handle.net/10481/87165 2024-01-23T12:48:01Z

FFRC and SASW nondestructive evaluation of concrete strength from early ages Martínez Soto, Fernando; Ávila Cruces, Fernando José; Puertas García, María Esther; Gallego Sevilla, Rafael Free-Free Resonant Column and Spectral Analysis of Surface Waves are two nondestructive testing techniques which are becoming increasingly relevant in construction engineering, as they offer the possibility of assessing the mechanical properties of the building materials without damaging the sample. In the present study, these two testing methods are applied on concrete samples with increasing curing times, from 9 h to 60 days, estimating the dynamic elastic modulus and proposing relationships to obtain the compressive strength from these values. The nondestructive results are compared with the actual strength of the material obtained via uniaxial compression tests, proving the accuracy of the proposed nondestructive testing methodologies, even for early ages. SASW tests are also carried out on a reinforced concrete sample, concluding that the presence of the reinforcement does not alter the results of the test. Keywords: Concrete; Early-age concrete; NDT; SASW; FFRC

Suárez, Elisabet Roldán Aranda, Andrés María Gallego Molina, Antolino Benavent Climent, Amadeo https://hdl.handle.net/10481/47290 2021-06-15T12:08:39Z

Entropy Analysis for Damage Quantification of Hysteretic Dampers Used as Seismic Protection of Buildings Suárez, Elisabet; Roldán Aranda, Andrés María; Gallego Molina, Antolino; Benavent Climent, Amadeo Relative wavelet energy entropy (RWEE) is proposed to detect and quantify damage to hysteretic dampers used for the passive seismic control of building structures. Hysteretic dampers have the role of dissipating most of the energy input of an earthquake. Minor or moderate earthquakes do not exhaust the energy dissipation capacity of the dampers, yet they damage them. For this reason, continuous or periodic damper-health evaluation is required to decide if they need to be replaced. Such evaluation calls for the application of efficient structural health monitoring techniques (SHM). This paper focuses on the well-known vibration technique, which is applied to a particular type of hysteretic damper called Web Plastifying Damper (WPD), patented by the University of Granada. Vibration signals, properly recorded by piezoelectric sensors attached around the damaged area of the dampers, are decomposed by means of wavelet packet analysis. Then, the relative wavelet energy entropy of these decompositions is used to calculate the proposed index. Validation of RWEE for this particular application involved dampers installed in two different specimens of reinforced concrete structures subjected to earthquake sequences of increasing intensity. When compared with a well-established mechanical energy-based damage index, results demonstrate that RWEE is a successful and low-cost technique for reliable in-situ monitoring of dampers.