Analysis of the stress state at the double-step joint in heavy timber structures

J. R. Villar-García; P. Vidal-López; J. Crespo; M. Guaita

doi:10.3989/mc.2019.00319

Autores/as

J. R. Villar-García Departamento de Ingeniería del Medio Agronómico y Forestal, Centro Universitario de Plasencia, Universidad de Extremadura https://orcid.org/0000-0003-1283-606X
P. Vidal-López Grupo de Investigación Ingeniería Mecánica y Fluidos, Departamento de Ingeniería del Medio Agronómico y Forestal, Universidad de Extremadura https://orcid.org/0000-0002-8941-604X
J. Crespo Plataforma de Ingeniería de la Madera Estructural, Escuela Politécnica Superior, Universidad de Santiago de Compostela https://orcid.org/0000-0003-1517-4030
M. Guaita Plataforma de Ingeniería de la Madera Estructural, Departamento de Ingeniería Agroforestal, Universidad de Santiago de Compostela https://orcid.org/0000-0001-9159-7348

DOI:

https://doi.org/10.3989/mc.2019.00319

Palabras clave:

Madera, Análisis de elementos finitos, Modelización, Propiedades mecánicas, Deformación

Resumen

Entre las uniones carpinteras, el embarbillado doble es una de las más utilizadas para transmitir cargas superiores a las que permitiría una única entalladura, especialmente interesante para estructuras pesadas. Hoy en día, la fabricación asistida por ordenador ha estimulado su uso, demandando profundizar en su estudio. El diseño convencional de estas uniones se realiza asumiendo supuestos simplificadores, en particular respecto a la distribución de las tensiones tangenciales en el cogote. Derivando en el empleo de factores de penalización de la resistencia, los cuales continúan actualmente en estudio. Se realizaron ensayos con escuadrías propias de cerchas pesadas en configuración par-tirante, empleándose para ello madera laminada. Los gráficos experimentales de carga-deformación y carga-desplazamiento se compararon con la modelización numérica de la unión. Esto permitió apreciar la importante concentración de tensiones tangenciales que se produce en el fallo por rasante, lo que aconseja la aplicación de factores reductores de resistencia a cortante conservadores.

Descargas

Los datos de descargas todavía no están disponibles.

Citas

Villar, J.R.; Vidal, P.; Fernández, M.S.; Guaita, M. (2016) Genetic algorithm optimisation of heavy timber trusses with dowel joints according to Eurocode 5. Biosyst Eng. 144, 115-132. https://doi.org/10.1016/j.biosystemseng.2016.02.011

Parisi, M.A.; Piazza, M. (2000) Mechanics of plain and retrofitted traditional timber connections. J. Struct. Eng. 126, 1395-1404. https://doi.org/10.1061/(ASCE)0733-9445(2000)126:12(1395)

Villar, J.R.; Guaita, M.; Vidal, P.; Arriaga, F. (2007) Analysis of the Stress State at the Cogging Joint in Timber Structures. Biosyst Eng. 96, 79-90. https://doi.org/10.1016/j.biosystemseng.2006.09.009

Villar, J.R.; Guaita, M.; Vidal, P.; Argüelles, R. (2008) Numerical simulation of framed joints in sawn-timber roof trusses. Spanish J. Agric. Res. 6, 508-520. https://doi.org/10.5424/sjar/2008064-345

Villar-García, J.R.; Crespo, J.; Moya, M.; Guaita, M. (2018) Experimental and numerical studies of the stress state at the reverse step joint in heavy timber trusses. Mater Struct. 51:17. https://doi.org/10.1617/s11527-018-1144-9

Feio, A.O.; Lourenço, P.B.; Machado, J.S. (2014) Testing and modeling of a traditional timber mortise and tenon joint. Mater Struct. 47, 213-225. https://doi.org/10.1617/s11527-013-0056-y

Parisi, M.A.; Cordié, C. (2010) Mechanical behaviour of double-step timber joints. Constr. Build. Mater. 24, 1364-1371. https://doi.org/10.1016/j.conbuildmat.2010.01.001

Branco, J.M.; Piazza, M.; Cruz, P.J.S. (2011) Experimental evaluation of different strengthening techniques of traditional timber connections. Eng. Struct. 33, 2259-2270. https://doi.org/10.1016/j.engstruct.2011.04.002

Palma, P.; Cruz, H. (2007) Mechanical behaviour of traditional timber carpentry joints in service conditions-results of monotonic tests. Proc. 16th Int. Conf. From Mater. to Struct. - Mech. Behav. Fail. Timber Struct. ICOMOS Int. Wood Comm.

Palma, P.; Ferreira, J.; Cruz, H. (2010) Monotonic tests of structural carpentry joints. World Conf. Timber Eng. (2010).

Verbist, M.; Branco, J.M.; Poletti, E.; Descamps, T; Lourenço, PB. (2017) Single Step Joint: overview of European standardized approaches and experimentations. Mater Struct. 50, 161. https://doi.org/10.1617/s11527-017-1028-4

CEN EN 1995-1-1:2016. Eurocode 5 : Design of timber structures - Part. 1.1 General. Common rules and rules for buildings.

CTE-DB-SE-M 2009 Spanish Technical Building Code, Structural Security, Timber Structures.

NEN NEN-EN 1995-1-1+C1+A1:2011/NB:2013nl. National Annex to NEN-EN 1995-1-1+C1+A1 Eurocode 5: Design of timber structures - Part 1-1: General - Common rules and rules for buildings.

SIA 265:2012. Timber Structures. Swiss Society of Engineers And Architects.

Argüelles Álvarez, R.; Arriaga, F.; Esteban, M.; Íñiguez, G.; Argüelles Bustillo, R. (2015) Estructuras de Madera. Uniones (Timber Structures. Joints), AITIM. Asociación de Investigación Técnica de las Industrias de la Madera y Corcho. Madrid.

Aira, J.R.; Íñiguez-González, G.; Guaita, M.; Arriaga, F. (2016) Load carrying capacity of halved and tabled tenoned timber scarf joint. Mater Struct. 49, 5343-5355. https://doi.org/10.1617/s11527-016-0864-y

CEN EN 14080:2013. Timber structures. Glued laminated timber and glued solid timber. Requirements.

Argüelles Álvarez, R. (1992) Fundamentos de elasticidad y su programación por elementos finitos, (Fundamentals of elasticity and finite element programming), Bellisco. Madrid, (1992).

Ortiz Berrocal, L. (2007) Resistencia de Materiales (Strength of Materials), 3rd ed, MCGRAW-HILL, Madrid.

CEN EN 408:2011+A1:2012. Timber structures - Structural timber and glued laminated timber - Determination of some physical and mechanical properties.

Koch, H.; Eisenhut, L.; Seim, W. (2013) Multi-mode failure of form-fitting timber connections - Experimental and numerical studies on the tapered tenon joint. Eng. Struct. 48, 727-738. https://doi.org/10.1016/j.engstruct.2012.12.002

Baño, V.; Argüelles-Bustillo, R.; Regueira, R.; Guaita, M. (2012) Determination of the stress-strain curve in specimens of Scots pine for numerical simulation of defect free beams. Mater. Constr. 62 [306], 269-284. https://doi.org/10.3989/mc.2012.64110

Sangree, R.H.; Schafer, B.W. (2009) Experimental and numerical analysis of a halved and tabled traditional timber scarf joint. Constr. Build. Mater. 23, 615-624. https://doi.org/10.1016/j.conbuildmat.2008.01.015

Soilán, A.; Arriaga, F.; Baño, V.; Crespo, J.; Guaita, M. (2011) Analysis of the behaviour of the dovetail connection by numerical simulation with the finite element method. In: Joao Negrao y Alfredo G. Dias, editor. Proceeding 1er Ibero-Latin Am. Congr. wood Constr. CIMAD 11., Coimbra, Portugal.

Aira, J.R. (2013) Análisis experimental y por el método de los elementos finitos del estado de tensiones en uniones carpinteras de empalme de llave. PhD thesis, Universidad Politécnica de Madrid.

ANSYS Inc. ANSYS® (2012) Academic Research, Release 14.0: Help System: ANSYS Mechanical APDL theory reference.

Tsai, S.W.; Wu, E.M. (1971) A General Theory of Strength for Anisotropic Materials. J. Compos. Mater. 5, 58-80. https://doi.org/10.1177/002199837100500106

Guindos, P. (2011) Three Dimensional Finite Element Models to Simulate the Behaviour of Wood with Presence of Knots, Appling The Flow-Grain Analogy and Validation with Close Range Photogrammetry. PhD thesis, University of Santiago de Compostela.

Goldenblat, I.I.; Kopnov, V.A. (1965) Strength of glass reinforced plastics in the complex stress state. Polym. Mech. 1, 54-59. https://doi.org/10.1007/BF00860685

Cabrero, J.M.; Gebremedhin, K.G.; Elorza, J. (2009) Evaluation of Failure Criteria in Wood Members. ASABE Annu. Int. Meet., American Society of Agricultural and Biological Engineers. ASABE. Reno, Nevada, EE.UU. (2009).

Eberhardsteiner, J. (2002) Mechanisches Verhalten von Fichtenholz. Vienna: Springer Vienna. https://doi.org/10.1007/978-3-7091-6111-1

Schmidt, J.; Kaliske, M. (2008) Models for numerical failure analysis of wooden structures. Eng. Struct. 31, 571-579. https://doi.org/10.1016/j.engstruct.2008.11.001

Dahl, K.B. (2009) Mechanical properties of clear wood from Norway spruce. PhD thesis, Norwegian University of Science and Technology.

Resch, E.; Schmidt, J.; Gereke, T.; Kaliske, M. (2004) GröBe und Einfluss der Streuung der elastischen Eigenschaften von Fichtenholz. (Size and influence of the dispersion of the elastic properties of spruce). LACER. 9, 417-432.

Bucur, V. (2006) Acoustics of wood. 2nd ed., Springer- Verlag Berlin Heidelberg, (2006). https://doi.org/10.1007/3-540-30594-7 PMCid:PMC1995072

Majano-Majano, A.; Fernández-Cabo, J.L.; Hoheisel, S.; Klein, M. (2012) A Test Method for Characterizing Clear Wood Using a Single Specimen. Exp. Mech. 52, 1079-1096. https://doi.org/10.1007/s11340-011-9560-6

Vázquez, C.; Gonçalves, R.; Bertoldo, C.; Baño, V.; Vega, A.; Crespo, J. (2015) Determination of the mechanical properties of Castanea sativa Mill. using ultrasonic wave propagation and comparison with static compression and bending methods. Wood Sci. Technol. 49, 607-622. https://doi.org/10.1007/s00226-015-0719-7

Gonçalves, R.; Trinca, A.J.; Cerri, D.G.P. (2011) Comparison of elastic constants of wood determined by ultrasonic wave propagation and static compression testing. Wood Fiber Sci. 43, 64-75.

Conde-García, M.; Fernández-Golfín Seco, J.I.; Hermoso Prieto, E. (2007) Improving the prediction of strength and rigidity of structural timber by combining ultrasound techniques with visual grading parameters. Mater. Constr. 57 [288], 49-59. https://doi.org/10.3989/mc.2007.v57.i288.64

UNE 56543, Características físico-mecánicas de la madera. Determinación del esfuerzo cortante (Physical-Mechanical Properties of Wood. Determination of the Shear Strength).

ASTM D143:14 Standard test methods for small clear specimens of timber. ASTM International, West Conshohocken, PA

Aira, J.R.; Arriaga, F.; Íñiguez-González, G.; Crespo, J. (2014) Static and kinetic friction coefficients of Scots pine (Pinus sylvestris L.), parallel and perpendicular to grain direction, Mater. Constr. 64 [315], e030. https://doi.org/10.3989/mc.2014.03913

Crespo, J.; Regueira, R.; Soilán, A.; Díez, M.R.; Guaita, M. (2011) Methodology to determine the coefficients of both static and dynamic friction apply to different species of wood. In: Joao Negrao y Alfredo G. Dias, editor. Proceeding 1er Ibero-Latin Am. Congr. wood Constr. CIMAD 11, Coimbra, Portugal.

Smith, I.; Landis, E.; Gong, M. (2003) Fracture and Fatigue in Wood, Wiley, Chichester, (2003).

DIN EN 1995-1-1/NA:2013. Nationaler Anhang. National festgelegte parameter. Eurocode 5: Bemessung und konstruktion von reglen für den hochbau. (National Annex. Nationally determined parameters. Eurocode 5 : Design of timber structures Common rules and rules for buildings).

Bocquet, J.F. (2015) Traditional structural assemblies in the future regulatory context. Eurocode 5: design and calculation of wooden structures. Formation ENSTIB. National School of Wood Science and Timber Engineering - University of Lorraine, Nancy, Lorraine, (2015).

Aira, J.R.; Arriaga, F.; Íñiguez-González, G. (2014) Determination of the elastic constants of Scots pine (Pinus sylvestris L.) wood by means of compression tests. Biosyst Eng. 126, 12-22. https://doi.org/10.1016/j.biosystemseng.2014.07.008

Colling, F. (2008) Holzbau, Vieweg+Teubner, Wiesbaden, (2008). doi:10.1007/978-3-8348-9551-6. https://doi.org/10.1007/978-3-8348-9551-6 PMCid:PMC3556514

Aira, J.R.; Descamps, T.; Van Parys, L.; Léoskool, L. (2015) Study of stress distribution and stress concentration National School of Wood Science and Timber Engineering - University of Lorraine, Nancy, Lorraine, (2015). https://doi.org/10.1007/s00107-015-0891-3