Abstract
The theory of layered beams (TLB) was developed over 80 years ago for the structural elastic analysis of
wooden beams assembled with nails and screws. Recently, it has been demonstrated that TLB is also suitable for the
analysis of cross-laminated timber (CLT) beams under out-of-plane and in-plane loading. In this paper, the history of
TLB is briefly outlined, and the theory is applied to the analysis of CLT beams under moisture and temperature loadings. When adopting TLB, it is possible to derive analytical solutions for simple structures, and exact finite
element formulations are available for more complex cases. In this paper, TLB is used for CLT beam analysis under moisture and temperature actions, and new analytical solutions are derived. It can be concluded from the findings
presented in the paper that TLB provides a sound and systematic basis for the structural analysis of CLT beams.
Key Words
cross-laminated timber; layered beam theory; moisture loading; temperature loading
Address
Markku Heinisuo, Sami Pajunen: Unit of Civil Engineering, Tampere University, P.O. Box 600, 33100 Tampere, Finland
Abstract
The growing urgency to reduce emissions and raw material consumption has made circular economy (CE) models increasingly relevant in the construction industry. In this context, concrete incorporating recycled aggregates (RAC) from construction and demolition waste (C&DW) represents a promising approach. However, uncertainties persist regarding the durability of such materials. This study evaluates the water-related durability of self-compacting concrete (SCC) with varying levels of recycled aggregate substitution (0%, 50%, and 100%), enhanced with superplasticisers (SP). Four key durability tests were conducted: freeze-thaw cycles, capillary absorption, total water absorption, and water penetration under pressure. Results indicate that while freeze-thaw performance is limited by surface porosity, the presence of SP improves resistance to internal water-related degradation mechanisms. The RAC-SCC mixes exhibited comparable or even superior performance to conventional natural aggregate concretes (NAC) in terms of impermeability and water absorption. These findings confirm the viability of RAC-SCC for structural applications, contributing to sustainable construction and the implementation of CE principles.
Key Words
atmospheric agents; circular economy; concrete; construction waste; durability; recycled aggregates; self-compacting concrete; superplasticizer; testing; water
Address
Víctor Baladrón-Blanco, Rebeca Martínez-García: Department of Mining Technology, Topography, and Structures, University of León, Campus of Vegazana s/n, 24071 León, Spain
Daniel Merino-Maldonado, Andrea Antolín-Rodríguez, Andrés Juan-Valdés: Department of Agricultural Engineering and Sciences, University of León, Avenida de Portugal 41, 24009 León, Spain
Abstract
This research presents a numerical study to investigate the influence of node flexibility on the seismic performance and fragility of medium- to high-rise base-isolated buildings. A computational program was also developed to design the isolator bearings used in the models, enabling a comprehensive evaluation of both structural response and isolation performance. The results confirm that seismic isolation effectively reduces inter-story drifts and minimizes both structural and non-structural damage. Moreover, semi-rigid connections were found to increase target displacements up to twice those of rigid connections while reducing shear forces by approximately 30%. The study further indicates that isolation systems are particularly effective for low- and medium-rise structures, whereas taller buildings may experience a risk of shear failure at the bearing supports, where semi-rigid connections can provide a more favorable solution. Overall, the findings offer valuable insights into the interplay between node flexibility and seismic isolation, highlighting both the advantages and limitations of these strategies for enhancing the seismic resilience of medium- to high-rise buildings.
Address
Said H. Boukhalkhal: Faculty of Civil Engineering, University of Sciences & Technology Houari Boumediene of Algiers (USTHB), BP.32 El-Alia, Bab Ezzouar, 16111, Algiers, Algeria; Department of Civil Engineering, University of Djelfa, Djelfa, 17000, P.O.B. 3117, Algeria; Laboratory of Mechanics and Materials Development, University of Djelfa, PO Box 3117, 17000, Djelfa, Algeria
Soumia Taleb: Department of Civil Engineering, University of Djelfa, Djelfa, 17000, P.O.B. 3117, Algeria; Laboratory of Mechanics and Materials Development, University of Djelfa, PO Box 3117, 17000, Djelfa, Algeria
Abd Nacer T. Ihaddoudène: Faculty of Civil Engineering, University of Sciences & Technology Houari Boumediene of Algiers (USTHB), BP.32 El-Alia, Bab Ezzouar, 16111, Algiers, Algeria
Abdallah Y. Rahmani: Department of Civil Engineering, University of Djelfa, Djelfa, 17000, P.O.B. 3117, Algeria
Abstract
Currently, seismic design of structures has evolved due to new advanced approaches that consider variables associated with damage, which is particularly beneficial for structures susceptible to cumulative inelastic damage, such as those made of reinforced concrete and braced elements. For example, several energy-based design methodologies (EBDM) have been proposed that aim to achieve safer structures through plastic deformation analysis and seismic energy balance. Therefore, in this paper a new EBDM for dual systems composed of reinforced concrete and buckling restrained braces (RCBRB) is presented, specifically tailored for the Mexico City lake-bed zone. This approach is based on transformation factors between single (SDOF) and multi-degree-of-freedom (MDOF) systems to calculate global demands. These demands are distributed to each inter-story and structural element using proposed distribution equations. Finally, the local design is accomplished by comparing the local energy demands with the hysteretic energy dissipation capacity (CEH) using a set of proposed equations. The new approach is applied to the seismic design of two three-dimensional dual systems of 9- and 12-story buildings. To validate this new EBDM, the results are evaluated through inelastic dynamic time-history analyses, demonstrating the proposed approach's potential to design safe structures in terms of maximum inter-story drift, ductility, energy and damage.
Key Words
buckling restrained braces; dual systems; energy dissipation capacity; energy-based design; reinforced concrete
Address
Herian Leyva: Facultad de Ingeniería, Arquitectura y Diseño, Universidad Autónoma de Baja California, Ensenada 22860, México
Edén Bojórquez: Facultad de Ingeniería, Universidad Autónoma de Sinaloa, Culiacán 80040, México
Juan Bojórquez: Facultad de Ingeniería, Universidad Autónoma de Sinaloa, Culiacán 80040, México
Luigi Di Sarno: 3epartment of Civil and Environmental Engineering, University of Liverpool, Liverpool, UK
Alí Rodríguez: Facultad de Ingeniería, Universidad Autónoma de Sinaloa, Culiacán 80040, México
Alfredo-Reyes-Salazar: Facultad de Ingeniería, Universidad Autónoma de Sinaloa, Culiacán 80040, México
Manuel Barraza: Facultad de Ingeniería, Arquitectura y Diseño, Universidad Autónoma de Baja California, Ensenada 22860, México
Mario Llanes: Facultad de Ingeniería, Universidad Autónoma de Sinaloa, Culiacán 80040, México
Benouis Ali, Zagane Mohammed El Sallah, Moulgada Abdelmadjid, Murat Yaylaci, Ait Kaci Djafar, Şevval Öztürk, Ecren Uzun Yaylaci, Yilmaz Güvercin, Mehmet Emin Özdemir
Abstract
This study aims to assess the impact of defects on the reliability and service life of hip prostheses. To understand crack behavior in hip prostheses, specifically in the acetabular part, the stress intensity factor (SIF) was
evaluated, accounting for crack interactions within orthopedic cement and at the bone-cup interface. The analyses were carried out using programs based on the Finite Element Method (FEM). The study reveals that significant stress concentrations occur at the bone interface, particularly under different orientations of the femoral implant. In addition, the study analyzed the relationship between the physical changes in the crack on the prosthesis and the stress intensity factor across various modes. Results indicate that cracks initiated at the cement contour can propagate by opening and shearing the cracked lips.
Key Words
cement; crack; fracture; prosthesis; stress intensity factor (SIF)
Address
Benouis Ali: LISMH, Dr. Moulay Tahar, University of Saida, Bp 138 Saida, 20000, Algeria; LMPM, Djillali Liabes University of Sidi Bel-Abbes, Algeria
Zagane Mohammed El Sallah: LMPM, Djillali Liabes University of Sidi Bel-Abbes, Algeria; University of Ibn Khladoun, Tiaret, 14000, Algeria
Moulgada Abdelmadjid: LMPM, Djillali Liabes University of Sidi Bel-Abbes, Algeria; University of Ibn Khladoun, Tiaret, 14000, Algeria
Murat Yaylaci: Department of Civil Engineering, Recep Tayyip Erdogan University, 53100, Rize, Türkiye; Biomedical Engineering MSc Program, Recep Tayyip Erdogan University, 53100, Rize, Türkiye; Dijitalpark Teknokent, Murat Yaylaci-Luzeri R&D Engineering Company, 53100, Rize, Türkiye
Ait Kaci Djafar: LMPM, Djillali Liabes University of Sidi Bel-Abbes, Algeria
Şevval Öztürk: Department of Civil Engineering, Recep Tayyip Erdogan University, 53100, Rize, Türkiye
Ecren Uzun Yaylaci: Faculty of Fisheries, Recep Tayyip Erdogan University, 53100, Rize, Türkiye
Yilmaz Güvercin: Department of Orthopaedic and Traumatology, Trabzon University, 61030, Trabzon, Türkiye
Mehmet Emin Özdemir: Department of Civil Engineering, Cankiri Karatekin University, 18100, Çankiri, Türkiye
Abstract
Functionally graded materials (FGMs) possess spatial variation of material properties that can be customized to meet specific application based requirements. These materials offer scope to design mechanical structures with a different combination of material properties need to be balanced. This study presents a multi objective optimization of FGM using a genetic algorithm (GA) to achieve an optimal balance between strength and weight. The FGM considered here is graded with 0-2 weight % of graphene nano platelets (GPLs) experimentally in the transverse direction and the gradation is formularized as per one parameter power low function. The GA was employed to explore range of configuration, which helps in identifying the best gradation profile with higher weight to strength ratio. Experimental validation was conducted to access the efficacy of the optimization tool. A close approximation was found between the experimental and GA result in the FGM sample, showing its robustness in handling such optimization scenario.
Address
Akankshya Priyadarshini, Mihir Kumar Sutar, Sarojrani Pattnaik: Department of Mechanical Engineering, Veer Surendra Sai University of Technology, Burla, India
open access
