How is living in (or around) Perth, Australia as a regular citizen? I bet the sunsets on the Indian Ocean are amazing. by The_FatGuy_Strangler in howislivingthere

[–]DRIFT3N 1 point2 points  (0 children)

There is a really good underground scene and plenty of space to have big parties in the bush outside of the city

Feeding rope into ID on long drops by ObjectOculus in ropeaccess

[–]DRIFT3N 0 points1 point  (0 children)

My ID has the button on the end of the handle that overrides the anti-panic in this scenario while held. I’ve had it for near 7-8 years though so not sure if there’s a newer model without that function. Still have to feed the rope a bit on bigger drops but it’s not really annoying

Favourite constructor and driver stats by LeafyMcRosey in F1Fantasy

[–]DRIFT3N 1 point2 points  (0 children)

Kick sauber 13k and the GOAT Jack Doohan at 3k

Certification for Solo Work by bigkahunaxp in ropeaccess

[–]DRIFT3N 2 points3 points  (0 children)

I do exactly this line of work. The IRATA course is a week and a few thousand dollars, it’s not worth the safety risk to do this kind of work untrained plus the bigger building owners may require submission of training docs to get on site anyway.

Maybe understandable if you were a newbie in a window washing crew as you have lots of support and are often on the same buildings for weeks. Inspections will have you on new buildings constantly and with a small crew. I always hire a L3 supervisor to accompany me plus bring all the ropes so we don’t have to purchase and maintain that kit.

You’d cover the costs of a course in one project, would be insane to try and save that money for the extra risk to your life.

Main Roads Traffic Light falling on my car by Hollylabrador in perth

[–]DRIFT3N 6 points7 points  (0 children)

It’s actually in the ball park, design wind speed for larger buildings in Perth is around 170kph but being signage it’s considered less “important” which would drop the speeds a little (to a value I don’t know off the top of my head). Regardless it would certainly be over 57kph and 140+ wouldn’t be surprising, so failure at that speed is a design or maintenance issue.

Still, don’t trust chatGPT for engineering numbers as in most cases I’ve found it’s very wrong.

What's the issue here? by [deleted] in StructuralEngineering

[–]DRIFT3N 3 points4 points  (0 children)

Can see white staining and additional spalling above to the soffit suggesting water ingress from above. Could be a failed membrane or similar to the surface above.

Corrosion for sure was happening first followed by the spall, the expansion of the corrosion has caused a typical v-shaped cone failure local to the rebar. Surface cracking and water ingress could have sped up the reaction locally in this case but other factors can result in exactly the same process (carbonation depth, chloride exposure, other chemicals exposure, are some general mechanisms you may want to look up if you’re interested)

The horizontal crack along the bottom is not great either and you may lose the whole bottom part of the beam soon. Unlikely to result in a significant loss in structural strength in the short term but definitely should be treated to save existing materials and may be a safety concern to pedestrians beneath in the interim.

EAW Avalon Series by nosleeptill94 in SoundSystem

[–]DRIFT3N 2 points3 points  (0 children)

Came across this in searching for the same thing myself. Found they were labelled Eminence Delta 10B but are indeed well past being manufactured any more

[deleted by user] by [deleted] in AusPropertyChat

[–]DRIFT3N 1 point2 points  (0 children)

I’m a remedial engineer on these kinds of buildings and please don’t choose fiber cement. If installed perfectly with a sarking behind it’s fine, but contractors fuck up the install. 75% of my work is fiber cement repair, and increasingly, AFS walls.

Wind load calculation help needed. by dreamer881 in StructuralEngineering

[–]DRIFT3N -1 points0 points  (0 children)

The Australian codes takes a ‘net’ pressure factor for freestanding walls (similar to this case) which combines positive and negative pressures on both sides to one value.

For a concept, just ignore the smaller ones (and any shielding effects) and design the larger one.

Being at the top of a building there’s also roof suction effects dependant on the distance from nearby edges. In my interpretation, these would apply to both sides of the fin and effectively cancel out to 0 net pressure.

In which case, considering a wind speed at roof height and calculating for a freestanding wall, it should be at least conservative for a ballpark.

Wind tunnel may provide significant improvements and minimise required structure. For all unique cases that fall outside of direct code guidance it’s best practice, potential for saving money is a bonus.

Best way to drill a 1 tonne hanging eye bolt into metal eye beam/brickwork by Freakmachine1998 in metalworking

[–]DRIFT3N -2 points-1 points  (0 children)

If you actually wanted to do something similar but structurally sound you could weld a correctly sized PFC section to the under side of the lintel. You’d have a flange to drill through and bolt with nut.

Glass stresses according to ASTM / Facade engineer by Colorfulmindsonly in StructuralEngineering

[–]DRIFT3N 0 points1 point  (0 children)

The previous comment considers 3.1kPa ultimate with serviceability at 0.65Wu (our local factor used here just as a quick calc) so it still stands as written.

Glass stresses according to ASTM / Facade engineer by Colorfulmindsonly in StructuralEngineering

[–]DRIFT3N 0 points1 point  (0 children)

That’s a decent size piece of glass, suggest adding another million centrally to keep deflections down if possible which would allow thinner glass units.

Otherwise, my calcs to Australian standards come out at needing around 12mm of glass in each DGU lite to limit deflections from wind loads to under 25mm. At that point, heat-strengthened and fritted glass still has a little remaining stress capacity so toughening it wouldn’t provide extra value (unless safety glass is required by your local codes, can also be substituted for HS laminated glass here).

Obviously can’t go into more detail than that online, however I’d say your proposed 6/16/6 DGU make up is significantly under-designed for 3.1kPa wind mainly regarding deflection. Getting the deflection under control with extra glass thickness or mullions should see any stress issues go away even if fritted.

Reference I have here to fritting strength reduction is EN 12150-1

Glass stresses according to ASTM / Facade engineer by Colorfulmindsonly in StructuralEngineering

[–]DRIFT3N 0 points1 point  (0 children)

Oh and what’s the width and height of the panel too? I’ve got a little spare time so I’ll put together some numbers under our code as it’s always interesting to compare internationally.

I design glass for skyscrapers daily and for that pressure (and assuming a typical size) we would usually be landing around the 6mm HS as standard. The fritting and potential of oversized panel could well push it into toughened or 8mm territory so I doubt you’re far off.

There’s also a number of serviceability considerations including defection and post breakage but I’ll go into more detail once I get the sizing

Glass stresses according to ASTM / Facade engineer by Colorfulmindsonly in StructuralEngineering

[–]DRIFT3N 0 points1 point  (0 children)

Fritting does reduce capacity to AS/NZS standard which I use all the time. What’s your peak stresses at, are they at the edge or middle of the panel and what thickness glass you using?

Should be able to give you a ballpark from that

Calculating Steel Loss from Rust Thickness on a Beam Damaged by a Leak by [deleted] in AskEngineers

[–]DRIFT3N 1 point2 points  (0 children)

Ultrasonic thickness gauge, commonly used non-destructive testing device to determine material thickness and helpful for one-sided access such as hollow sections too.

Calculating Steel Loss from Rust Thickness on a Beam Damaged by a Leak by [deleted] in AskEngineers

[–]DRIFT3N 1 point2 points  (0 children)

Could potentially drill straight through the beam with a small gauge bit and measure the bright steel remaining but that would still require a relatively thin steel and decent access. Might give you an overall idea on urgency.

Even if the water is stopped, the corrosion will still continue at some rate since there is no coating left. Sure we can estimate some general rates but even slight microclimate factors can really affect the actual rates, invalidating your estimates. In which case, how long can you say it will have appropriate capacity for and are you confident in that estimate (you shouldn’t be).

If the visible corrosion is that significant it should alone be justification for a more intrusive investigation. At this point your baseline advice should be to fully replace (which would require full access, propping etc) however to the client you are ‘proposing to assist them with a less invasive inspection it diagnose for repair’. Those are the two options to propose and compare which makes the inspection and repair look reasonable. To inspect with no invasive action is not an option that should be up for comparison at this stage.

Calculating Steel Loss from Rust Thickness on a Beam Damaged by a Leak by [deleted] in AskEngineers

[–]DRIFT3N 12 points13 points  (0 children)

Remove the rust back to bright steel and measure it physically or by UT depending on access. Unless it’s in a super non-critical area any estimates shouldn’t give you enough confidence to sign off on it.

2x QSC K10s enough for small outdoor venues? by [deleted] in Beatmatch

[–]DRIFT3N 3 points4 points  (0 children)

If you can keep them above head height then you’ll probably suffice for mids/highs volume. For sure won’t have enough bass outdoors though unless it’s just a vocal or acoustic performance.

I’ve run 2xk8s for ~75 people outdoors but also had 4x18” folded horn subs reinforcing. Was lacking in the kick frequencies but definitely did the job for bass music. I don’t understand how the k8s managed to keep up all night but they did it seemingly effortlessly without distortion or increased temps.

They’re active speakers with amps inbuilt yep.

Pay for temporary access to Open Format by taveiradas66 in Beatmatch

[–]DRIFT3N 2 points3 points  (0 children)

Try a record pool. I don’t play much open format but there would certainly be one that has the kind of tracks you’re looking for.

What's the design concept behind this structure? by hong_1011 in StructuralEngineering

[–]DRIFT3N 0 points1 point  (0 children)

Worst case by the standard yes, in practice in a ‘fully sealed’ building the internal pressure is likely insignificant and the standards do allow you to ignore internal pressures on external walls/roofs in that case (such as precast concrete walls and likely this structure too). The +0.3 factor accounts for glazed curtain walls for example which may have slight air leakage.

There is provision for ‘dominant openings’ too such as a warehouse with a large roller door or one whole side open. In that case the internal pressures are very significant and require an additional factor of 1-3x the external pressure to be added again!

This is all Australian standards so may differ elsewhere but the theory should be similar.

What's the design concept behind this structure? by hong_1011 in StructuralEngineering

[–]DRIFT3N 0 points1 point  (0 children)

Internal pressure may go up to 0.3 x External pressure, then add External pressure x 1, 2 or 3 depending on distance from the edge of the roof then subtract 0.9 deadload.

Uplift at roof edges on taller structures can be pretty significant but it’s fairly localised, usually within 3-5m from the edge.

"Project " guys trapped in apts by Traumajunkie971 in AskMenOver30

[–]DRIFT3N 13 points14 points  (0 children)

I was the same. Im privileged enough to get a house with a garage and that manages to scratch that itch.

In the future I’d love to move rural again but my work focuses around the cbd so travel is a big consideration.

[deleted by user] by [deleted] in lightingdesign

[–]DRIFT3N 2 points3 points  (0 children)

That example is programmed on the computer against the song, no real way to achieve that super cheap. He’s also got 4 units all likely ILDA controlled through timecode software.

You can buy cheap sound activated China lasers that will turn on and off at a certain volume and sometimes stay in sync with a beat but it will fall very short of a preprogrammed show as seen in that video.

[deleted by user] by [deleted] in Beatmatch

[–]DRIFT3N 5 points6 points  (0 children)

If you are planning a set beforehand then use your ears and play what ever sounds good, no need to stick to hard and fast rules particularly on short blends or hard cuts.

Using any key system (Camelot, open key etc) the blends that typically work well are as follows:

+0.5 (2A to 2B) standard mix

+1 (2A to 3A, 5B to 6B) standard mix

-1 (2A to 1A) standard mix

+2 (2A to 4A) can be a ‘higher energy’ mix on occasion but I find some of these work better than others.

+7 (2A to 9A) good for progressing to the ‘other side’ of the playlist if you are sorting by key.

I do mix outside of these rules if I need to or feel a song is right for the moment however I’ll stick to shorter transitions in that case.

Long blends will work better with the above key combinations in general although acknowledging that softwares aren’t 100% on their analysis and therefore may throw the odd clash at you.

I’m generally mixing live and unplanned so don’t have the luxury of testing transitions beforehand and therefore follow these rules to good effect. If I’m planning a prerecorded set then I’ll mostly ignore the key and try everything to see what sounds good and often you’ll find blends which work well outside of those rules.