Publications de Till Vallée | EPFL Graph Search

Shear loaded friction-welded crosswise arranged timber boards

Till Vallée, Yves Weinand, Benjamin Hahn

Friction welding of wood is a bonding technology that can be used for joining timber elements, and in which the adhesive is formed from thermally modified cell wall material within the substrate during the welding process. In this paper, this principle is ...

2017

Moment resisting connections composed of friction-welded spruce boards: experimental investigations and numerical strength prediction

Bernhard Stamm, Till Vallée, Yves Weinand, Benjamin Hahn

Research on friction welded wood-to-wood connections has shown high potential for further development regarding the industrial application of timber construction. This paper addresses the question to which extent welding of wood can be applied to fabricati ...

Springer Verlag2014

Experimental Investigations and Probabilistic Strength Prediction of welded Double Lap Joints composed of Timber

Bernhard Stamm, Till Vallée, Yves Weinand, Benjamin Hahn

Wood-to-wood bonds obtained by means of friction welding are a relatively new type of connections holding high potential to compete with existing structural adhesives, since a load bearing bond is formed almost instantaneously. This paper addresses the que ...

Elsevier2012

Experimental investigations on welded double lap joints composed of timber

Bernhard Stamm, Till Vallée, Yves Weinand, Benjamin Hahn

Fabrication of wood-to-wood connections by means of friction welding is an relatively new process holding high potential for development. To connect wooden pieces by means of friction welding, they are initially pressed against each other. The rapid moveme ...

Elsevier Science, Reg Sales Off, Customer Support Dept, 655 Ave Of The Americas, New York, Ny 10010 Usa2011

Numerical modelling and strength prediction of welded double lap joints made of timber

Bernhard Stamm, Till Vallée, Yves Weinand, Benjamin Hahn

Welding of wood is a relatively new method of joining load bearing elements, which holds the potential to compete with structural adhesion, since it allows for an almost instantaneous bond. First experimental and numerical investigations showed that failur ...

Elsevier Ltd. Selection2011

Shear resistance of lightweight concrete core of FRP-concrete sandwich structure

Thomas Keller, Till Vallée, Erika Schaumann

This paper presents a model to predict the shear resistance of the unreinforced lightweight concrete core of a recently developed hybrid sandwich concept for bridge decks. The sandwich skins consist of a fiber-reinforced polymer (FRP) composite sheet for t ...

2009

Optimum thickness of joints made of pultruded GFRP adherends and polyurethane adhesive

Thomas Keller, Till Vallée

This paper presents results of experimental and numerical investigations on double-lap joints composed of pultruded GFRP profiles and polyurethane adhesive subjected to quasi-static axial tensile loading. The objective was to investigate the effect of the ...

2009

Delamination of pultruded glass fiber-reinforced polymer composites subjected to axial compression

Thomas Keller, Till Vallée, Yu Bai

Axial compression experiments were conducted on pultruded E-glass fiber-reinforced polymer laminates of different slenderness. Second-order deformations greatly increased the bending moments and shear forces of slender specimens. Delamination failure occur ...

2009

Adhesively bonded joints composed of pultruded adherends: considerations at the upper tail of material strength statistical distribution

Thomas Keller, Till Vallée

The Weibull distribution, used to describe the scaling of strength of materials, has been verified on a wide range of materials and geometries; however, the quality of the fitting tended to be less good towards the upper tail. Based on a previously develop ...

2009

Modeling of direct load transmission in sandwich beams with lightweight concrete

Thomas Keller, Till Vallée, Erika Schaumann

The direct load transmission behavior of hybrid sandwich beams consisting of a bottom fiber-reinforced polymer skin and a top concrete skin was investigated experimentally. The sandwich core consisted of lightweight concretes of different brittleness (sand ...

2009

Pultruded GFRP posts for railway noise barriers

Thomas Keller, Till Vallée, Florian Riebel

142 (abstract), paper on CD-ROM ...

2008

Acoustic emission analysis and acousto-ultrasonics for damage detection in GFRP adhesive joint

Thomas Keller, Till Vallée

2008

Direct load transfer in hybrid FRP-concrete sandwich structure for bridge decks

Thomas Keller, Till Vallée, Erika Schaumann

2008

Direct load transmission in hybrid FRP and lightweight concrete sandwich bridge deck

Thomas Keller, Till Vallée, Erika Schaumann

Direct load transmission experiments on hybrid short-span beam specimens for a novel bridge deck were performed. The sandwich construction consists of three layers: a fiber- reinforced polymer composite (FRP) sheet with T-upstands for the bottom skin, ligh ...

2008

GFRP posts for railway noise barriers – experimental validation of load-carrying performance and durability

Thomas Keller, Till Vallée, Florian Riebel

As part of a 15-year railway noise remediation plan, 300km of noise barriers will be installed in Switzerland over the next few years. To enable pultruded glass fiber- reinforced polymer (GFRP) materials to be used for the noise barrier posts, a specificat ...

2008

Direct load transmission in sandwich slabs with lightweight concrete core

Thomas Keller, Till Vallée, Erika Schaumann

CRC Press2008

Modeling of thermo-mechanical properties and responses for FRP composites in fire

Thomas Keller, Till Vallée, Yu Bai

2008

Direct load transfer in hybrid FRP-concrete sandwich structure for bridge decks

Thomas Keller, Till Vallée, Erika Schaumann

2008

Flexural behavior of a hybrid FRP-concrete sandwich bridge deck

Thomas Keller, Till Vallée, Erika Schaumann

2008

Structural concept, design and experimental verification of a GFRP sandwich roof structure

Thomas Keller, Till Vallée

This paper reports on the design and construction of a lightweight glass fiber-reinforced polymer roof structure in Basel, Switzerland. The sandwich construction allowed for an integration of static, building physical and architectural functions that enabl ...

2008