Journals
Magazine:
BULLETIN OF EARTHQUAKE ENGINEERING
ISSN:
1570-761X
Year:
2023
Vol:
21
Ppgs:
739 - 766
This study presents the analysis of the methodology of a seismic exposure model in Guatemala City. In the last years, progress in the investigation of regional seismic hazards has revealed the need to study the vulnerability of buildings in Central America. In addition, in recent years there have been earthquakes of moderate magnitude in Guatemala causing damage in some areas of the country. An accurate exposure model and updated threat scenarios are essential for a detailed vulnerability study. This exposure study for Guatemala City reveals the presence of structural typologies that are very vulnerable to earthquakes: adobe and simple masonry. Similarly, the study reveals the majority presence of reinforced masonry and the growing construction of reinforced concrete buildings. The characteristic of this model is the use of historical aerial photographs of Guatemala City to determine the relationship between constructive typologies. The lack of exposure studies in the country has prevented the creation of policies to reduce vulnerability to a catastrophe like the earthquake in 1976. The analysis and methodology presented in this study are the preliminary step in formulating seismic risk prevention and mitigation plans in Guatemala City; knowledge of the city's exposure contributes to making subsequent actions more effective. Based on the results obtained, matrices are proposed according to the age and material of the buildings for the typological classification of the structures.
Magazine:
ENGINEERING STRUCTURES
ISSN:
0141-0296
Year:
2022
Vol:
266
Ppgs:
114556
The performance of structural timber connections is of utmost importance since they control the global response of the building. A ductile failure mechanism on the global scale is desirable, especially in the design of structures in seismic areas, where dissipative components in which ductile failure modes need to be ensured are considered. Therefore, the knowledge of possible brittle failure modes of connections is crucial. The paper investigates the brittle failures of laterally loaded dowel-type connections in cross-laminated timber subjected to tensile load in a lap joint configuration through experimental investigations and analytical estimations. A set of 13 different test series has been performed with fully threaded self-tapping screws of 8 mm diameter and different lengths (40 to 100 mm) in cross-laminated timber composed of 3 or 5 layers (layer thickness range from 20 to 40 mm), giving rise to the activation of different brittle failure modes at different depths. Plug shear was among the most typically observed failure modes. A previously proposed model for the brittle capacity was applied to the tested connections at the characteristic level. As shown by the performed statistical analysis, the existing model is not reliable and mainly unconservative. A very low performance is observed (CCC = 0.299), but with a good correlation (c = 0.750) for the tests in the parallel direction. Further research work is required to improve the current model predictions and to gain a better understanding of the underlying resisting mechanisms.
Magazine:
CIC CONSTRUCTION INFORMATION CENTER
ISSN:
1576-1118
Year:
2022
Vol:
575
Ppgs:
62 - 64
Magazine:
CIVILENG
ISSN:
2673-4109
Year:
2022
Vol:
3
N°:
3
Pp:
610 - 629
Authors:
Araya, R. (Corresponding author); Guillaumet, A.; do Valle, A.; et al.
Magazine:
SUSTAINABILITY
ISSN:
2071-1050
This article presents the latest developments of the Spanish- and Portuguese-speaking countries of Europe and Latin America towards the development of sustainable timber construction. As most regions related to these countries have not traditionally employed timber as primary construction material, bringing the development of sustainable timber construction into fruition requires a wide range of actions, such as the elaboration of new educational programs, construction of demonstrative buildings, dissemination activities, settlement of public policies, elaboration of new construction codes, and the creation of new certification bodies. This article presents an overview of the state of the development of the different countries of Ibero-America, showing a very uneven development in the region. In addition to national analyses, a perception survey of 233 professionals from different countries was conducted, allowing for the identification of good practices, present gaps, and opportunities, as well as barriers for developing sustainable timber construction. It is concluded that in order to promote the development of the timber construction industry in the region, it is necessary to progress on regulatory, cultural, and material availability issues, where international experience, demonstrative buildings, and the implementation of public policies are crucial.
Magazine:
MORE WOOD
ISSN:
2695-4583
Year:
2022
Vol:
16
Ppgs:
44 - 50
Magazine:
ENGINEERING STRUCTURES
ISSN:
0141-0296
Year:
2021
Vol:
235
Pgs:
112062
Finite element models tend to overestimate the actual elastic response of structural timber connections. The paper shows how such overprediction relates to the modelling of the contact between fasteners and timber. The use of a control parameter called stiffness contact is proposed. After an experimental campaign, a method to determine it, based only on the geometry of a rectangular contact area, is proposed. The modeling adequacy is demonstrated by applying it to dowel embedment and moment resistant wood joint tests. The obtained results show good agreement with the experimental test series.
Magazine:
ENGINEERING STRUCTURES
ISSN:
0141-0296
Year:
2021
Vol:
241
Ppgs:
112450
Timber connections with steel dowel-type fasteners may fail in ductile or brittle ways. The design of these joints was traditionally focused on ductile failure, assuming that brittle failure could be avoided by means of geometrical limitations. However, recent studies demonstrated that these assumptions do not always guarantee ductile failure. A new design model for timber connections with small diameter dowel-type fasteners is provided in this paper. Its improved accuracy is demonstrated by analysing an extensive database of experimental tests and comparing its prediction accuracy to that of existing models.
Magazine:
MORE WOOD
ISSN:
2695-4583
Year:
2021
N°:
15
Pp:
40 - 46
Magazine:
ENGINEERING STRUCTURES
ISSN:
0141-0296
Year:
2021
Vol:
238
Pgs:
111766
Timber connections with small diameter fasteners that do not go through the whole timber member (such as screws or nails). may fail in brittle or ductile ways. In order to better understand their behaviour, an experimental campaign of tests of connections with small diameter fasteners loaded parallel-to-grain has been performed. The results and analysis of this work provide further information on the role of different parameters in the brittle failure. Existing models are benchmarked against these tests.
Magazine:
MORE WOOD
ISSN:
2695-4583
Year:
2021
N°:
15
Pp:
20 - 23
Magazine:
ENGINEERING STRUCTURES
ISSN:
0141-0296
Year:
2021
Vol:
247
Ppgs:
113122
The development of accurate structural modelling techniques is required to promote the use of timber as a renewable alternative to other structural materials. Due to their remarkable influence on the global behaviour of a timber structure, an accurate description of the performance of structural connections is needed. Particularly in the case of moment transmitting beam-to-column connections with dowel-type fasteners, such properties are difficult to obtain experimentally. This paper develops a finite element (FE) model that simulates the behaviour of these connections under quasi-static loading, with a focus on the estimation of rotational stiffness and load distribution among the dowels. The model is validated against short-term laboratory tests. Resulting friction between timber members due to the installation procedure must be considered, as it greatly influences the rotational response. Besides, non-linear behaviour of timber and a softened contact parameter have been implemented, and their influence on the FE model validation process is demonstrated.
Magazine:
ENGINEERING STRUCTURES
ISSN:
0141-0296
Year:
2021
Vol:
242
Ppgs:
112496
Timber connections can fail in a ductile or in a brittle way. A structural design that guarantees a ductile behaviour in case of failure is desirable, especially when facing extreme situations such as earthquakes. This work discusses how the European Yield Model (based on a ductile failure mechanism), included in many standards, combined with a reduction of the effective number of fasteners may provide too conservative results, which may inadvertently lead to risky situations in which a connection assumed to fail under a ductile mechanism would actually fail in a brittle manner. Within this paper, a proposal to improve the discrimination ability to correctly predict the failure mode is proposed.
Magazine:
ENGINEERING STRUCTURES
ISSN:
0141-0296
Year:
2020
Vol:
209
Pgs:
109959
The consideration of brittle failure of timber connections requires an adequate evaluation of the capacity of the involved failure plans. Their correct geometrical definition is therefore of utmost importance to obtain an accurate assessment of their capacity. This article presents a new approach to account for the effective thickness of the lateral planes of timber members in connections with large diameter fasteners loaded parallel-to-grain when the fasteners remain in its elastic range, which allows to consider the uneven load distribution along the fastener in a simple way. The proposal is based on a fitting of a beam on elastic foundation model and only requires the slenderness of the fastener as a parameter. It provides a both simple and accurate way to calculate the effective thickness of timber elements.
Magazine:
ENGINEERING STRUCTURES
ISSN:
0141-0296
Timber connections may collapse in a brittle or in a ductile mode. The calculation models of timber joints are mainly focused on ductile failure mode, since it has been traditionally assumed that brittle failure was avoided by respecting a minimum spacing between fasteners. However, this assumption alone does not guarantee a ductile failure. This paper proposes a new design model dealing with brittle failure modes of timber connections with large diameter fasteners (those protruding the whole thickness of the timber member such as dowels or bolts). A comparison between the proposal and the existing models, using an extensive database of tests, is used to demonstrate the improved accuracy of the proposed design method.
Magazine:
ENGINEERING STRUCTURES
ISSN:
0141-0296
Magazine:
MORE WOOD
ISSN:
2695-4583
Year:
2020
N°:
14
Pp:
34 - 40
Magazine:
WOOD MATERIAL SCIENCE AND ENGINEERING
ISSN:
1748-0272
Year:
2019
Vol:
14
N°:
5
Pp:
298 - 311
Magazine:
MORE WOOD
ISSN:
2695-4583
Year:
2019
Vol:
13
Pgs:
34 - 40
Magazine:
CONSTRUCTION AND BUILDING MATERIALS
ISSN:
0950-0618
Year:
2019
Vol:
216
Pgs.:
296 - 313
Magazine:
AITIM TECHNICAL INFORMATION BULLETIN
ISSN:
0044-9261
Year:
2019
N°:
318
Pp:
4 - 9
Magazine:
NEW ZEALAND JOURNAL OF TIMBER DESIGN
ISSN:
1171-8323
Year:
2019
Vol:
27
N°:
3
Pp:
17 - 26
Magazine:
NEW ZEALAND JOURNAL OF TIMBER DESIGN
ISSN:
1171-8323
Year:
2019
Vol:
27
N°:
3
Pp:
17 - 26
Magazine:
MORE WOOD
ISSN:
2695-4583
Year:
2018
Vol:
12
Pgs:
32 - 37
Magazine:
CONSTRUCTION AND BUILDING MATERIALS
ISSN:
0950-0618
Year:
2018
Vol:
173
Pgs:
238 - 250
Magazine:
ENGINEERING STRUCTURES
ISSN:
0141-0296
Year:
2018
Vol:
171
Pgs:
895 - 910
For safety reasons, ductile failure in timber connections with dowel-type fasteners is always recommended. It has usually been assumed that it can be achieved by fulfilling minimum spacing requirements between fasteners. However, recent works address the need to account for brittle failure modes (namely splitting, row-shear, and block and plug-shear) in connections loaded parallel-to-the-grain in an explicit manner, in order to evaluate them and achieve the desired ductility. This article describes the brittle failure modes and reviews the existing calculation models proposed by several authors ¿ some of them included in standards. Finally, the performance of these models is assessed against an extensive database of tests gathered from the literature following a comprehensive methodology.
Magazine:
ENGINEERING STRUCTURES
ISSN:
0141-0296
Year:
2018
Vol:
170
Pgs:
135 - 145
Magazine:
NAVARRA FORESTAL
ISSN:
1579-8771
Year:
2017
N°:
41
Pp:
22 - 24
Magazine:
COMPOSITE MATERIALS
ISSN:
2531-0739
Year:
2017
Vol:
1
N°:
1
Pp:
105 - 109
Magazine:
MORE WOOD
ISSN:
0213-3741
Year:
2017
N°:
11
Pp:
36 - 41
Magazine:
MORE WOOD
ISSN:
0213-3741
Year:
2016
N°:
10
Pp:
28 - 33
Magazine:
ENGINEERING STRUCTURES
ISSN:
0141-0296
Year:
2016
Vol:
117
Pgs.:
332 - 343
Wood, as a natural heterogeneous material, is a challenging material to simulate. This work presents an algorithm to model both its elastic and post-elastic responses. It allows to model different compression and tension elastic and failure behaviors in both material directions, parallel and perpendicular to the grain. It employs two different strategies: a sequential application of different failure criteria, and the modelling of post-elastic response by means of damage and stress reduction parameters. The proposed algorithm is applied to spruce in two experimental cases with different loadings and failure modes. When reasonable mesh density and increment size are used, the obtained results are in good agreement with the experimental results. The proposed algorithm has been programmed in the commercial software ABAQUS. However, it may be easily applied to different platforms or wood species.
Magazine:
NAVARRA FORESTAL
ISSN:
1579-8771
Year:
2016
N°:
38
Pp:
36 - 38
Magazine:
NAVARRA FORESTAL
ISSN:
1579-8771
Year:
2016
N°:
39
Pp:
30 - 32
Magazine:
APPLIED MATHEMATICAL MODELLING
ISSN:
0307-904X
Year:
2015
Vol:
39
N°:
17
Pp:
5265 - 5277
Several methods for determining in-plane shear properties of anisotropic materials (i.e. fibre reinforced composite materials and natural wood) based on flexural loading have been proposed. One of those methods is the off-axis flexural test that considers unidirectional composite materials subject to three-point bending loading. As a result of the anisotropic behaviour, unidirectional off-axis laminates subjected to flexure present a bending¿twisting coupling that may cause, in the case of 3-point bending loading, a lift-off of the specimen on the fixture supports. Such specimen lift-off has been considered one of the critical features to be considered on the mentioned experimental method. Besides geometrical parameters, material elastic constants, as longitudinal, transversal and shear elastic moduli, influence the validity to use this method for characterising in-plane shear properties. On that sense, an analytical approach for studying the material conditions for which the application of the off-axis 3P-B test is adequate is presented.
Magazine:
MECHANICS OF MATERIALS
ISSN:
0167-6636
Year:
2015
Vol:
83
Pgs:
103 - 109
Recent biaxial experiments on clear-spruce wood allow to have a more complete understanding of fracture behavior of wood. An elliptic failure surface, like that of Tsai¿Wu, has been previously proposed as a failure surface. Previous works in this area have shown the need for further developments. In this study a new failure model that accounts for existing different couplings and interactions in the longitudinal compressive and tensional domains is presented. The model is based on the fracture behavior of clear spruce wood and related experimental works. The model is more accurate compared to existing phenomenological models.
Magazine:
MORE WOOD
ISSN:
0213-3741
Year:
2015
Vol:
9
Pgs:
30 - 33
Magazine:
NAVARRA FORESTAL
ISSN:
1579-8771
Year:
2014
N°:
35
Pp:
30 - 32
What if buying your house were like buying a car? Choose a basic model . the additional equipment, and receive it in the agreed time for the agreed price. The dream of constructing buildings as if they were industrial elements, taking advantage of all the benefits of mass production, may be possible. A Navarrese business , Modula, is trying to make it a reality.
Magazine:
MORE WOOD
ISSN:
0213-3741
Year:
2014
N°:
8
Pp:
30 - 34
Magazine:
EUROPEAN JOURNAL OF WOOD AND WOOD PRODUCTS
ISSN:
0018-3768
Year:
2014
Vol:
72
N°:
5
Pp:
699 - 702
In this paper, mechanical properties of the four Central American wood species Amapola (Pseudobombax ellipticum), Manchiche (Lonchocarpus castilloi), Pucte (Bucida buceras) and Santamaria (Calophyllum brasiliense) determined in a preliminary experimental study are presented.
Magazine:
NAVARRA FORESTAL
ISSN:
1579-8771
Year:
2014
N°:
34
Pp:
32 - 34
Magazine:
NAVARRA FORESTAL
ISSN:
1579-8771
Year:
2013
N°:
33
Págs:
34 - 36
Magazine:
MORE WOOD
ISSN:
0213-3741
Year:
2013
N°:
7
Págs:
30 - 33
Magazine:
NAVARRA FORESTAL
ISSN:
1579-8771
Year:
2013
N°:
32
Págs:
32 - 34
Magazine:
MORE WOOD
ISSN:
0213-3741
Year:
2013
Vol:
7
Pgs:
22 - 29
Magazine:
SPEND IN
ISSN:
1696-8158
Year:
2013
Vol:
59
Ppgs:
106 - 109
Magazine:
EUROPEAN JOURNAL OF WOOD AND WOOD PRODUCTS
ISSN:
0018-3768
Year:
2012
Vol:
70
N°:
6
Pp:
871 - 882
Many different phenomenological failure criteria have been proposed. These type of criteria do not explain the mechanism of failure itself. They merely identify failure (yes or no) and are usually regarded in practice as a simple and reliable tool for design. Most of them were developed for composite materials, but are extensively applied for wood. In this study, existing phenomenological strength criteria for orthotropic materials were applied to clear wood data. Instead of fitting the criteria to available experimental data, the criteria were used to predict failure of biaxial tests based on uniaxial strength. This procedure is closer to practice, and hence an answer to the question ¿is there any reliable failure criterion for wood?¿ Predictability of the criteria was assessed using normalisation procedure, and statistical significance of the difference of the means analysed. Based on the results, it can be concluded that a general criterion cannot be applied to predict failure, but should be chosen according to the biaxial stress state.
Magazine:
NAVARRA FORESTAL
ISSN:
1579-8771
Year:
2012
N°:
31
Págs:
34 - 37
Magazine:
NAVARRA FORESTAL
ISSN:
1579-8771
Year:
2012
N°:
30
Págs:
36 - 38
Magazine:
MORE WOOD
ISSN:
0213-3741
Year:
2012
N°:
6
Págs:
32 - 37
Magazine:
ANNALS OF FRACTURE MECHANICS.
ISSN:
0213-3725
Year:
2011
Vol:
28
Ppgs:
39 - 44
In the first part of this work a review of the different models of wood failure in multi-axial loading states proposed so far is made. This is followed by a statistical analysis of the adjustment of these criteria to experimental results, found in the literature, of tests carried out on white spruce wood under different loading conditions. Finally, a new non-continuous failure criterion is proposed with which, without increasing the issue of parameters required by other criteria, a better fit to the experimental data is obtained.
Magazine:
CONSTRULINK INTERNATIONAL MAGAZINE
ISSN:
1645-5576
Year:
2011
Vol:
9
N°:
28
Pp:
39 - 44
Magazine:
MORE WOOD
ISSN:
0213-3741
Year:
2011
N°:
5
Págs:
32 - 35
Magazine:
Composite Structures
ISSN:
0263-8223
Year:
2010
Vol:
92
N°:
12
Pp:
2955 - 2965
As a natural resource, an efficient use of wood should be also a requirement for structural timber design, but the usual structural solid sections do not achieve the required optimal behaviour. The performance of the structural elements (serviceability and strength) depends not only on the material properties, but mainly on the moment of inertia of the cross section. The Timber Construction Institute of Technische Universität Dresden has developed a process for the manufacture of structural wood profiles. The resulting profiles combine economy, an efficient use of the material and optimal structural performance. They are externally reinforced with composite fibres, which improve the mechanical characteristics of the wood and protect it from weathering. The available experimental tests to axial loading show the outstanding properties of this new technology. Herein, the preliminary model developed to obtain the axial strength of longitudinally compressed tubes is presented. Two different analytical algorithms are discussed and applied. The model adequately predicts the axial strength of fibre reinforced wood profiles. The analytical results are within an error less than 10% to the available experimental results, with a mean error ratio less than 3%.
National and Regional
degree scroll:
New methodology for the direct and automatic characterization of 2D beam-column joints, in steel and timber, by means of specialized metamodeling
based on deformation modes.
Code from transcript:
BIA2016-80358-C2-1-P
Funder:
MINISTRY OF SCIENCE AND INNOVATION
Call for proposals:
2016 MINECO EXCELLENCE. PROJECTS research and development
Start date:
30/12/2016
End date:
29/09/2020
Amount granted:
77.440,00€
Other funds:
ERDF funds
degree scroll:
development of a resistant element based on Lignumstrand for wood construction.
Code from transcript:
0011-1365-2017-000214
researcher principal:
José Manuel Cabrero Ballarín
Funder:
GOVERNMENT OF NAVARRA
Solicitation:
2017 GN research and development
Start date:
04/05/2017
End date:
22/07/2018
Amount granted:
43.425,73€
Other funds:
-
degree scroll:
Towards reliable and efficient analysis of wood joints: material and interaccon tests, and numerical modeling.
Code from transcript:
PID2020-118569GB-C21
researcher principal:
José Manuel Cabrero Ballarín
Funder:
STATE RESEARCH AGENCY
Call for proposals:
2020 AEI PROJECTS research and development+i (includes Generation of knowledge and Challenges research)
Start date:
01/09/2021
End date:
31/08/2025
Amount granted:
132.495,00€
Other funds:
-
degree scroll:
Innovative Solutions for Cross Laminated Structures Structures
Innovative Solutions for Cross Laminated Structures (Innovative Solutions for Cross Laminated Structures)
Code from transcript:
PCI2019-103591
Funder:
MINISTRY OF SCIENCE AND INNOVATION
Call for applications:
2019 MINECO APCIN
Start date:
01/03/2019
End date:
31/10/2022
Amount granted:
109.000,00€
Other funds:
ERDF funds
