Hi RattlinBog-
Your situation is somewhat familiar as I also have a 130+ year old house that was cobbled together with reused timbers and have also rehabbed a few of these ancients in my earlier life. My first thought was that sistering your 6x8 beam with full length LVL's isn't your best...
That's what good engineers do bigmig, we worry about things we don't know. Ignorance can't be offset by cost or schedule. Consider yourself enriched, now you know why you don't have to care about holes in flitch plates.
dauwerda-
That explanation belongs in the Eng_Tips top ten most thorough and eloquent replies ever written (on any subject !). It erases all doubt in my mind about the prevailing design practice for steel flitch beams.
I'm certain the information presented in this thread by yourself, phamEng...
XR250-
" . . . lost in the noise of the design . . ." could be a subtitle to what this thread is about. There should be no noise in design work especially where public safety is concerned, just ask the structural steel folks - they've got their act together.
Nails driven into wood beams and...
Very good phamENG, thank you for that.
You structural steel Code folks are awesome. But it amazes me that absolutely all of the prior Eng-Tips flitch beam discussions, all readily available published literature and the National Design Specifications and residential building codes (where steel...
dauwerda-
If you're still viewing - I'm fascinated by your reply; I gather the steel Codes that you mentioned allow a member to exceed yield when analyzing a member based on "net area" i.e., cross section minus area of holes, but what is the allowance criteria? how far past yield does the steel...
Hi StrucPatholgst-
I wonder if ClearCalcs adjusts the MOI & section modulus to account for bolt holes as we're discussing? I'll bet it doesn't (I know that a similar low cost software package, BeamChek does not).
Anyway, I can now run through a more thorough set of hand calcs, selecting...
ProgrammingPE-
This is a beautiful answer, you have validated my concern and at the same time, despite possible/probable yielding near a bolt hole or two at mid-span, nearly convinced me it won't make too much difference.
However, I think I favor the idea of avoiding any theoretical yielding...
I have an upcoming residential project that may require a stack of LVL's or perhaps a steel flitch beam configuration to replace a bearing wall spanning ~16 feet or so. To prepare, I've read as much of the available internet literature that I could find including the ubiquitous Destefano...
Hey CompositePro-
In your extreme example of a one liter hose between the cylinder and valve, I can see that the valve may struggle to crack open especially when the cylinder volume is small. So, yeah I'm beginning to accept that in actual practice, valve location just might make a difference !!
Yes 3DDave, "...other side of the valve integrates to the peak pressure...", that is a very eloquent way to describe the pressure buildup with each piston stroke and it shouldn't matter where the valve is located.
Thanks gruntguru but what you are saying is the same current wisdom that I am questioning, i.e. that a hose between cylinder and check valve adds to the clearance volume. But my claim is that with a check valve on the engine side of the setup, as soon as the valve opens (at a very low pressure)...
Hello Dave & Greg-
The Schrader valves used on compression tester have a much lower lift pressure than a tire valve, something on the order of ~4psi or less.
Thanks for your reply CompositePro -
I realize the gauge pressure reading will (ideally) be less than the actual pressure by an amount...
This question regards engine compression testers and the effect Schrader valve location has on accuracy of compression readings.
Background: typical automotive shop style compression testers consist of a pressure gauge attached to a flexible tube (typical ~16-inches long) with an adapter at its...
