Search results for: L. Romera

Items from 1 to 12 out of 12 results

article

Static crushing of aluminium tubes filled with PET foam and a GFRP skeleton. Numerical modelling and multiobjective optimization

M. Costas, D. Morin, M. Langseth, J. Díaz, more

International Journal of Mechanical Sciences > 2017 > 131-132 > C > 205-217

This investigation focuses on the multiobjective optimization of a crash box subjected to static loading by using a validated numerical model and an analytical approach. The crash box is made with a unique combination of three materials: an aluminium tube filled with polyethylene terephthalate (PET) foam and a glass-fibre reinforced polymer (GFRP) skeleton. A finite element model was calibrated based...

chapter

Nanoscale Agent Based Modelling for Nanostructure Development of Cement

E. Cerro-Prada, M. J. Vázquez-Gallo, J. Alonso-Trigueros, A. L. Romera-Zarza

Nanotechnology in Construction 3 > Regular Papers > 175-180

Most of macroscopic properties of materials are consequences of processes taking place at the nanoscale. Investigation of phenomena at the sub-micro level to improve the performance of construction materials is one of the main applications of Nanotechnology in Construction. The modelling and simulation of nanostructures is then essential to provide a better understanding of the behaviour of construction...

article

Axial crushing of aluminum extrusions filled with PET foam and GFRP. An experimental investigation

M. Costas, D. Morin, M. Langseth, L. Romera, more

Thin-Walled Structures > 2016 > 99 > C > 45-57

This research work investigated the axial crushing behavior of a circular aluminum extrusion in alloy AA6063-T5 internally reinforced with a glass–fiber structure and filled with polymeric foam. The components were experimentally tested under quasi-static and impact loading conditions supported by a material testing campaign. Energy absorption, crush force efficiency and specific energy absorption...

article

Size and shape optimization of aluminum tubes with GFRP honeycomb reinforcements for crashworthy aircraft structures

J. Paz, J. Díaz, L. Romera, M. Costas

Composite Structures > 2015 > 133 > C > 499-507

Crashworthiness optimization of aircraft and automotive structures has become one the main research targets for their respective leading industries. The following research proposes a new design of an aircraft’s vertical strut. The design consists of a hollow aluminum square tube with a glass-fiber reinforced polymer honeycomb-shaped inner structure. Size and shape surrogate-based optimization techniques...

article

A multi-objective surrogate-based optimization of the crashworthiness of a hybrid impact absorber

M. Costas, J. Díaz, L. Romera, S. Hernández

International Journal of Mechanical Sciences > 2014 > 88 > Complete > 46-54

This paper applies surrogate-based multi-objective optimization techniques to a crashworthiness problem in which the impact performance of a frontal crash absorber made of steel and a glass-fiber reinforced polyamide is optimized. Two well known crashworthiness indicators are considered as contrasting objective functions: the Specific Energy Absorption (SEA) and the Load Ratio (LR), whose responses...

article

Probabilistic assessment of the structural failure of single-lap bonded joints

J. Díaz, F. Pereira, L. Romera, S. Hernández

International Journal of Adhesion and Adhesives > 2012 > 37 > Complete > 70-78

Single-lap bonded joints are a common typology, frequently used when designing structural systems. Several authors have studied their behaviour in different situations, involving both failure of the adhesive and also of the adherends. So far, the design of such joints has been based on deterministic postulates. In this work, a non-deterministic approach is followed. The reliability of the joint is...

article

A computer code for finite element analysis and design of post-tensioned voided slab bridge decks with orthotropic behaviour

J. Díaz, S. Hernández, A. Fontán, L. Romera

Advances in Engineering Software > 2010 > 41 > 7-8 > 987-999

This paper presents a computer software which allows the generation of a complete structural model of a concrete bridge with a voided slab deck, a common design for medium span bridges. The code implements the orthotropic plate paradigm and provides a graphical user interface, which allows both preprocessing and post-processing, linked to a commercial finite element package. A description of the code...

article

Benchmarking of three-dimensional finite element models of CFRP single-lap bonded joints

J. Díaz, L. Romera, S. Hernández, A. Baldomir

International Journal of Adhesion and Adhesives > 2010 > 30 > 3 > 178-189

One of the challenges in the analysis and design of bonded joints is the evaluation of the stress and strain fields at the adhesive layer. Experimental work can be carried out in the laboratory in order to identify the ultimate load value, but numerical methods based on finite element models can be very useful in describing the stress and strain responses for each load step. In this work, the consideration...

article

Can urodynamic studies predict bladder behaviour changes after artificial urinary sphincter implantation?

P. López Pereira, I. Somoza, M.J. Martínez Urrutia, L. Romera, more

Journal of Pediatric Urology > 2005 > 1 > 6 > 397-401

To assess whether preoperative urodynamic studies can predict bladder behaviour changes that will necessitate bladder augmentation in patients with neuropathic incontinence after undergoing artificial urinary sphincter (AUS) implantation.We analysed 17 patients, with a mean age of 14.4 years at AUS implantation, who did not undergo bladder augmentation either before or at implantation. All patients...

article

Potassium iodide catalysed monoalkylation of anilines under microwave irradiation

Juan L. Romera, José M. Cid, Andrés A. Trabanco

Tetrahedron Letters > 2004 > 45 > 48 > 8797-8800

A potassium iodide catalysed method for the selective N-monoalkylation anilines with alkylhalides and alkyltosylates under microwave irradiation is described. The corresponding N-alkylanilines are obtained in good yields with only minor quantities of dialkylation by-products.

article

Selective α-monoallylation of phenyl ketones and benzocycloalkanones under microwave irradiation

José M. Cid, Juan L. Romera, Andrés A. Trabanco

Tetrahedron Letters > 2004 > 45 > 6 > 1133-1136

A method for the selective α-monoallylation of phenyl ketones and benzocycloalkanones with allyl alcohol under microwave irradation is described. The corresponding α-allyl ketones are obtained in moderate to good yields with only minor quantities of diallylation by-products.