Is it possible to remove the treated portion of a Creosote soaked pole? The aim is to be able to mill the pole into structural timber for use in a residential construction context. Would this be a legal solution?
If the pole is hardwood the creosote has most likely only penetrated the outer band of sapwood. Theoretically the sapwood could be sawn off, leaving a square of clean timber that could be re-sawn into smaller sizes if desired. However, in practice there are a few unknowns. The main issue is that although penetration will be largely confined to the sapwood, creosote will have penetrated more deeply via any cracks that were pre-existing in the wood at the time of treatment. Also if the pole is softwood, penetration is likely to be deeper. Of course if the pole was only treated by soaking one end to protect the in-ground zone it would be a simple matter to cut off the end, but we assume you are talking about full-length treatment. It also depends on the proposed use of the recovered material. We don't see any problem if traces of creosote remain in the wood, and it is used outdoors out of reach, for example rafters in a pergola. Creosote is a skin irritant and has a strong odour, so it would not be suitable indoors in a location accessible to hand contact. And the presence of creosote would be likely to interfere with standard coating systems. Broadly speaking, we are not greatly in favour of the idea, but this information will help you to make your own assessment.
I'm after someone who can visually verify timber grade in installed timber trusses in Newcastle area.
Your timber trusses can be visually stress graded in situ as long as access is available and all surfaces are visible. Australian Standard 2858 contains grading rules for softwoods, and Australian Standard 2082 for hardwoods. We don't have a contact in the Newcastle area but we suggest you contact Timber Training at Creswick. They have a website at www.timbertrainingcreswick.com.au. Since they run courses on visual stress grading they may be able to put you in touch with a qualified timber grader. Note that visual grading is a different process from machine grading and may produce a more conservative outcome. Also visual grading produces the F-grade series, whereas MGP pine grades can only be produced by machine. The different methods of grading timber are explained on our website here: https://www.woodsolutions.com.au/structural-grading.
Can you tell me where I can get details of Poisson's ratios for AU timber used for power poles?
Since timber has strongly directional characteristics there are six Poisson's ratios. However, the two related to timber with the grain running along the length of the member, loaded in tension or compression acting longitudinally, are μLR and μLT. The first subscript refers to the direction of applied load and the second subscript to the direction of lateral deformation. Unfortunately we aren't aware of Poisson's ratios having been calculated for Australian species. Ratios are available for a range of US species and can be found on the net via this link: https://www.fpl.fs.fed.us/documnts/fplgtr/fplgtr113/ch04.pdf. This might help you to approximate Poisson's ratios for the species in question.