Comosite Beam using Plastic Wood and Aluminum or GRP.

[MPHenry]

I am interested in hearing from anyone who has any experience of using Re-cycled Plastic wood in Composite Beam Construction. I intend to use a commercially available Plastic Wood section, e.g. 2x6, and form a composite beam using 2 sections of plastic wood along with a 5mm thk. flitch plate of either aluminum or Glass Reinforced Plastic. The composite will be constructed by bonding the sections together using an adhesive. What adhesive should I use which will perform in an externally exposed hot and humid climate? I think finding the right adhesive which can be applied on site will be the big problem. I do not wish to use bolts to form the composite beam as the beams will be directly exposed and aesthetics are important. Can anyone help?<br>
Regards<br>
Mike

 

[jimbo]

There is a 'Adhesives & Sealants' forum under Plastics (Things). You may get some info there by posting the same.

 

[merbas]

henry,<br>
1. Did you cast FIBERMESH road? how is results.<br>
2. Do you mean exposed beam and plastic wood PPCP window frames joints? pls open a bit the subject.<br>
3. How did you make exposed beam? I donot under stand.<br>
bye<br>

 

[JC]

I have noticed the plastic wood beams and planks, used in outdoor tables and swing sets in my neighborhood, have problems with deflection. I don't know if there is any strength reduction in the members but it doesn't look good. Be careful!

 

[MPHenry]

JC<br>
Plastic Wood has a very low Modulus of Elasticity approx. 20 times lower than timber for an equivalent section size. Therefore, deflection is off critical importance when using this material in any sort of a structural manner. By using GRP as part of a composite construction I hope to control the deflection by increasing the overall E value of the section. The bending strength of Plastic Wood is equivalent to Timber (Douglas-Fir)if not higher in some cases. The 3M Company is currently investigating the appropriate adhesive to use. Will keep you all posted on any developments.<br>
Regards<br>
Mike