The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
B W Schafer - One of the best experts on this subject based on the ideXlab platform.
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experimental and numerical analysis of a halved and tabled traditional timber Scarf Joint
Construction and Building Materials, 2009Co-Authors: R H Sangree, B W SchaferAbstract:Abstract Traditionally constructed heavy timber trusses, found in timber framed buildings and bridges, employ various traditional Joints, among them the lower chord Scarf Joint. This paper examines the behavior of a halved and tabled Scarf Joint, which was studied as an isolated structural component using experimental tests and finite element analyses. Experimental tests identified two different limit states for these particular Scarf Joints: shear failure parallel to grain and tension failure perpendicular to grain. The possibility of failure due to tension perpendicular to grain results from variations in grain angle and means that the limit state of shear failure parallel to grain, typically assumed in analysis and design, is unconservative. For the purposes of design and rehabilitation, the authors propose that the Scarf Joint be treated as a member subject to combined bending and axial tension forces. The results of the finite element analysis, performed using solid continuum elements in ABAQUS, are in good agreement with the experimental test results. In addition to finite element models, the authors use analytical spring models to demonstrate that when developing a two-dimensional model of a truss with lower chord Scarf Joints, serviceability limit states be checked with a model that reduces the lower chord section properties in the vicinity of the Scarf Joints.
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experimental and numerical analysis of a stop splayed traditional timber Scarf Joint with key
Construction and Building Materials, 2009Co-Authors: R H Sangree, B W SchaferAbstract:Abstract Traditionally constructed heavy timber trusses employ Scarf Joints to transfer tensile forces between lower chord members. Scarf Joints significantly impact the global stiffness of heavy timber trusses, yet little is known about their structural behavior. This paper describes a study recently completed on the commonly used stop-splayed Scarf Joint with a key. Experimental tests were performed on Scarf Joints replicated from a covered wooden bridge in Pennsylvania and compared to the numerical results of full, three-dimensional finite element models created using ABAQUS. The authors determined that the key has the most influence on Scarf Joint behavior as its orientation causes it to be loaded in compression perpendicular to grain. Experimental tests also revealed the importance of clamping bolts, without which a limit state of “key rolling” was observed. With two clamping bolts in place, the limit state was shear failure parallel to grain, which provides a more stable failure and a higher ultimate strength. The authors recommend to engineers that the Scarf Joint not be analyzed as a pure tension member; rather, it should be considered a member subject to combined tension and bending forces.
R H Sangree - One of the best experts on this subject based on the ideXlab platform.
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experimental and numerical analysis of a halved and tabled traditional timber Scarf Joint
Construction and Building Materials, 2009Co-Authors: R H Sangree, B W SchaferAbstract:Abstract Traditionally constructed heavy timber trusses, found in timber framed buildings and bridges, employ various traditional Joints, among them the lower chord Scarf Joint. This paper examines the behavior of a halved and tabled Scarf Joint, which was studied as an isolated structural component using experimental tests and finite element analyses. Experimental tests identified two different limit states for these particular Scarf Joints: shear failure parallel to grain and tension failure perpendicular to grain. The possibility of failure due to tension perpendicular to grain results from variations in grain angle and means that the limit state of shear failure parallel to grain, typically assumed in analysis and design, is unconservative. For the purposes of design and rehabilitation, the authors propose that the Scarf Joint be treated as a member subject to combined bending and axial tension forces. The results of the finite element analysis, performed using solid continuum elements in ABAQUS, are in good agreement with the experimental test results. In addition to finite element models, the authors use analytical spring models to demonstrate that when developing a two-dimensional model of a truss with lower chord Scarf Joints, serviceability limit states be checked with a model that reduces the lower chord section properties in the vicinity of the Scarf Joints.
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experimental and numerical analysis of a stop splayed traditional timber Scarf Joint with key
Construction and Building Materials, 2009Co-Authors: R H Sangree, B W SchaferAbstract:Abstract Traditionally constructed heavy timber trusses employ Scarf Joints to transfer tensile forces between lower chord members. Scarf Joints significantly impact the global stiffness of heavy timber trusses, yet little is known about their structural behavior. This paper describes a study recently completed on the commonly used stop-splayed Scarf Joint with a key. Experimental tests were performed on Scarf Joints replicated from a covered wooden bridge in Pennsylvania and compared to the numerical results of full, three-dimensional finite element models created using ABAQUS. The authors determined that the key has the most influence on Scarf Joint behavior as its orientation causes it to be loaded in compression perpendicular to grain. Experimental tests also revealed the importance of clamping bolts, without which a limit state of “key rolling” was observed. With two clamping bolts in place, the limit state was shear failure parallel to grain, which provides a more stable failure and a higher ultimate strength. The authors recommend to engineers that the Scarf Joint not be analyzed as a pure tension member; rather, it should be considered a member subject to combined tension and bending forces.
M Guaita - One of the best experts on this subject based on the ideXlab platform.
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load carrying capacity of halved and tabled tenoned timber Scarf Joint
Materials and Structures, 2016Co-Authors: Jose R Aira, Guillermo Iniguezgonzalez, M Guaita, Francisco ArriagaAbstract:The stress distribution of timber tenoned Scarf Joint subjected to tension force was analysed by means of finite element method. This analysis was compared and validated with results from an experimental work on 42 specimens of Scots pine wood (Pinus sylvestris L.) with 48 × 148 mm in cross-section and 1932 mm, in length, manufactured with a tenoned Scarf Joint in the middle of its length. Specimens were divided in eight groups corresponding to different Joint geometries. A plane finite element analysis using ANSYS software was made considering the elasticity moduli, Poisson ratios and friction coefficients obtained in previous research works for the same material. Three different failure modes were analysed: compression parallel to the grain in the notch area, shear parallel to the grain in the heel surface, and the combination of tension and bending moment in the effective cross-section of the piece, which is limited by the crack initiation due to tension perpendicular to the grain. Equations for the verification of this Joint are proposed as a practical conclusion.
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failure modes in halved and tabled tenoned timber Scarf Joint by tension test
Construction and Building Materials, 2015Co-Authors: Jose R Aira, Guillermo Iniguezgonzalez, Francisco Arriaga, M GuaitaAbstract:The structural behaviour of halved and tabled tenoned Scarf Joint subjected to tensile stresses was experimentally analysed to find the different failure modes. A total of 42 specimens of Scots pine wood (Pinus sylvestris L.) were made. Specimens were divided into 8 groups corresponding to different Joint geometries. Three different failure modes were observed: compression parallel to the grain in the notch area, shear parallel to the grain in the heel surface, and by cracking starting in the reduced cross-section. The load that caused crack initiation was obtained, and the influence of the length of the overlapping surface was analysed.
Jose R Aira - One of the best experts on this subject based on the ideXlab platform.
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load carrying capacity of halved and tabled tenoned timber Scarf Joint
Materials and Structures, 2016Co-Authors: Jose R Aira, Guillermo Iniguezgonzalez, M Guaita, Francisco ArriagaAbstract:The stress distribution of timber tenoned Scarf Joint subjected to tension force was analysed by means of finite element method. This analysis was compared and validated with results from an experimental work on 42 specimens of Scots pine wood (Pinus sylvestris L.) with 48 × 148 mm in cross-section and 1932 mm, in length, manufactured with a tenoned Scarf Joint in the middle of its length. Specimens were divided in eight groups corresponding to different Joint geometries. A plane finite element analysis using ANSYS software was made considering the elasticity moduli, Poisson ratios and friction coefficients obtained in previous research works for the same material. Three different failure modes were analysed: compression parallel to the grain in the notch area, shear parallel to the grain in the heel surface, and the combination of tension and bending moment in the effective cross-section of the piece, which is limited by the crack initiation due to tension perpendicular to the grain. Equations for the verification of this Joint are proposed as a practical conclusion.
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failure modes in halved and tabled tenoned timber Scarf Joint by tension test
Construction and Building Materials, 2015Co-Authors: Jose R Aira, Guillermo Iniguezgonzalez, Francisco Arriaga, M GuaitaAbstract:The structural behaviour of halved and tabled tenoned Scarf Joint subjected to tensile stresses was experimentally analysed to find the different failure modes. A total of 42 specimens of Scots pine wood (Pinus sylvestris L.) were made. Specimens were divided into 8 groups corresponding to different Joint geometries. Three different failure modes were observed: compression parallel to the grain in the notch area, shear parallel to the grain in the heel surface, and by cracking starting in the reduced cross-section. The load that caused crack initiation was obtained, and the influence of the length of the overlapping surface was analysed.
Francisco Arriaga - One of the best experts on this subject based on the ideXlab platform.
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load carrying capacity of halved and tabled tenoned timber Scarf Joint
Materials and Structures, 2016Co-Authors: Jose R Aira, Guillermo Iniguezgonzalez, M Guaita, Francisco ArriagaAbstract:The stress distribution of timber tenoned Scarf Joint subjected to tension force was analysed by means of finite element method. This analysis was compared and validated with results from an experimental work on 42 specimens of Scots pine wood (Pinus sylvestris L.) with 48 × 148 mm in cross-section and 1932 mm, in length, manufactured with a tenoned Scarf Joint in the middle of its length. Specimens were divided in eight groups corresponding to different Joint geometries. A plane finite element analysis using ANSYS software was made considering the elasticity moduli, Poisson ratios and friction coefficients obtained in previous research works for the same material. Three different failure modes were analysed: compression parallel to the grain in the notch area, shear parallel to the grain in the heel surface, and the combination of tension and bending moment in the effective cross-section of the piece, which is limited by the crack initiation due to tension perpendicular to the grain. Equations for the verification of this Joint are proposed as a practical conclusion.
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failure modes in halved and tabled tenoned timber Scarf Joint by tension test
Construction and Building Materials, 2015Co-Authors: Jose R Aira, Guillermo Iniguezgonzalez, Francisco Arriaga, M GuaitaAbstract:The structural behaviour of halved and tabled tenoned Scarf Joint subjected to tensile stresses was experimentally analysed to find the different failure modes. A total of 42 specimens of Scots pine wood (Pinus sylvestris L.) were made. Specimens were divided into 8 groups corresponding to different Joint geometries. Three different failure modes were observed: compression parallel to the grain in the notch area, shear parallel to the grain in the heel surface, and by cracking starting in the reduced cross-section. The load that caused crack initiation was obtained, and the influence of the length of the overlapping surface was analysed.
