Beiträge von goran mitic

Zitat von "Ich

Ohh... -.-
How do you know about all those accidents? Have you been working at these jobs?

Best wishes and RIP

I used to rig for local ground support company. In my ex-company we had two roof collapse, and numbers of 'small' accidents.
The lack of safety and continuous accidents made me quit the job.
But I still keep what is new in rigging over several rigging forums. That is how I know about those accidents.

I grow to learn, that a lot of people have trouble with those kind of posts. I wonder why is that so...

Right, so no posting on accidents?

I am sorry to post just bad news latelly...

RIP

http://www.commercialappeal.com/news/2008/jun/…apses-at-civic/

http://www.myeyewitnessnews.com/news/local/sto…d3-4317d54f88be

http://www.kake.com/news/headlines/19545914.html

I found this http://www.roadie.net/portal/html/up…oofcollapse.wmv,
but I could not find more info.
I guess all was well, since some people are making their speech at the end of the clip...

Hello Martin, Skyper,

skyper:
Thank you for your elaborative answer. You explained it very clearly.

@ Martin:
Thank you for that link. I will translate it and try to make something out of it... ich habe meine hausaufgabe immer zu hause fergessen, also meine Deutch is sehr schleht

(Real joke, happened to me: Once I wanted to say that I have a big wish to do something, so I said Ich habe eine grosse Wurst...)

Danke Alles

Hello Forum

I have searched, but I could not find... I am interested in angled trusses. How do I calculate forces on two points of a truss, when the truss is angled?

Also, there is a problem of getting the right span between points on truss in order for deadhangs to be vertical, but that is not a problem, really, as if I know left and right deadhang length, I could easily calculate needed space between points on truss.

The main question is, how to calculate the forces on point A and on point B, if truss is angled at certain degree (alpha)?
I was thinking, if I am tipping a truss over, the higher end should bear less load. But that seems too plain...
Is there some literature on this, or does anyone know how to approach the problem?

I would appreciate your input.

There is new thing happening:

http://roadienet.ning.com/

like myspace, but industry oriented...

(I would prefer any comments in english)

Zitat von "Marcus-pdm"

for the next time, download "LD Calculator" .....

with best regards..

Marcus

Dear Marcus,
LD Calculator is not having this function discussed in this thread, so I made my own.

Btw, LD Calculator does not have a lot of stuff that a rigging calculator should include.
It's bridle calculator is also not so easy to use, since you have to input a lot of data, that is usually not necessary. Today, with laser measuring devices (meters) is quickly measured height from floor to beam, so this is pretty much all you need,...

My free software for rigging is capable a bit more... and this function discussed in this thread is not yet available since I did not have time to put it in program, but hopefully by the end of the month I will do it.

So fell free to try it, http://www.beezgetz.com

Zitat von "Christian Hofmann"

Hi Goran,

can you please explain, how he get this? I'm interested to understand that, because I'm positive

Thanx

Hell, ok, here it is;
v1 = 8
v2 = 12
h1 = 4
h2 = 3
Bridle angle = 100 degrees
______________________

X = from floor to bridle junction (where d1 and d2 meets)

- tan(Bridle Angle) = V1H2-(H1+H2)X+V2H1 / H1H2-V1V2+(V1+V2)X - X^2

5.67128 = (8*3 - (4 + 3)*X + 12*4) / (4*3 - 8*12 + (8+12)*X - X*X)

5.67128 = (24 - 7*X + 48 ) / (12 - 96 + 20*X - X*X)

5.67128 = (72 - 7*X) / ( -84 + 20*X - X*X)

72 - 7*X = 5.67128 * ( -84 + 20*X - X*X)

72 - 7*X = -476.38752 + 113.4256*X - 5.67128*X*X

72 - 7*X + 476.38752 - 113.4256*X + 5.67128*X*X = 0

548.38753 - 120.4256*X + 5.67128*X*X = 0 ; so:

5.67128*X*X - 120.4256*X + 548.38753 = 0
______

Now, I don't know how this method is called in English, less in German, but it is also high school. we have power function, so we will get two results. one will be wrong, for our case, but mathematically they are both correct.

here is the formula:

x1 = (-b + square root of D) / 2a
x2 = (-b - square root of D) / 2a

where

D = b*b - 4*a*c

and

a is coefficient at second power operator (in our case 5.67128)
b is coefficient at first power operator (in our case - 120.4256)
c is linear operator (in our case 548.38753)

So:

D = 14502.32513536 - 4*5.67128*548.38753
D = 14502.32513536 - 12440.2369245536
D = 2062.0882108064

x1 = (- (- 120.4256) + square root of 2062.0882108064) / 2*5.67128
x1 = (120.4256 + 45.41022) / 11.34256
x1 = 165.8358 / 11.34256
x1 = 14.620669 so, this is wrong, since it is higher than at least one vertical.

x2 = (120.4256 - 45.41022) / 11.34256
x2 = 75.01538 / 11.34256
x2 = 6.613

Alas, from floor to bridle junction is 6.613. Now we can easily get triangles sides and calculate forces.

Hope this is understandable

I got this from Dutch guy, seems to do the trick;

ok, so V3 is the height from floor to bridle junction, with this formula we get V3, and rest is simple.

- tan(Bridle Angle) = V1H2-(H1+H2)V3+V2H1 / H1H2-V1V2+(V1+V2)V3-V3^2

Guten Tag Forum,

Thank you for your posts!

@ Gast
You really did a load of work, thanx. But I can not follow; what are G and K?
I am looking forward for your explanation!

@ Hasenfuß
it is theoretical question. I don't think in practice it ever comes to this, but if it is possible, I would like to include it in my program...

@ Christian
Huh, are you positive? If I need one more variable (argument) than my whole deal is off...
I don't know the answer, So I posted question.

@ Martin
In practice this is never the case, but as I said if there is a theoretical way I'd like to know it.

Hello and thanks for quick reply!

@ Martin,
We don't know alpha 1 on 2.
We know only green lines, v1, v2, h1, h2 and bridle angle.

otherwise I am sorry for Sunday morning... heh

@ Gast
please do post... I don't mind if is long

Thank you

Hello

Sorry, this thread will be in English

I want to add a new feature to my rigging software, but I can not make the formulas. It is about bridle, and I would appreciate your help.

We know left and right vertical height (from floor to beam).
We know left and right horizontal lengths (from beam to load, from load to beam).
We know bridle angle.
What are bridle legs (lengths)

here is the picture for better understanding.

Thank you,

Kind regards, Goran

Hey Christian, hello!

Your English is perfect!

Right. You are right, this could be a virus. As you download file on your Desktop PC you can check it out for viruses, since pocket pc are not well with security. But it is not virus program - I am not that much of a programmer...

And I did not make setup file - no installation is necessary, no extra memory usage! It is plain .exe file that you tap on to run.

And there is only one way to know if it is virus. Make a backup, and download my application and run it... :wink:

Zitat von "Christian Hackmann"

Ich beantrage hiermit das Teil vorher sauber durchzuchecken!

Weiß selber was man alles machen kann wen man eigenen Source aufn PocketPC kriegt... *grins*

Was gibts dümmeres als seine Viren selbst instaliert zu haben...?

Dies soll keinesfalls ein Vorwurf oder ähnliches sein!
Aber wie heißt es so schön: "Safety first!"

Hello Chris,

I am sorry, but there is no need to write in German in this particular topic.
Ich habe immer meine hausaufgabe zu hause fergessen, also sprechen auf English, bitte. Viele Danke!
Don't get me wrong, English is not my native language, But if we are to communicate, please rewrite your post in English. It is silly to expect that I will learn German. I do try to write a word or two in German, but with that I try to 'get closer' to you people. If you can not make a step towards me, well I can respect that.

Zitat von "Hami"

Dear Goran,

thanks a lot, I will tryout your FREEware in a few days. Seems to be really helpful.

With best regards from germany,

Thomas Hamacher

Keine Problem!

I was born in Socialistic republic where theoretically everybody should have access to everything.

But that is not the main reason I have this for free. It has to do with safety reasons.

Please try it, and I could do with little critics!

Regards from Slovenia!

Hello pa-forum, I am sorry for my German, I don't speak well, so.... English?

Since technology moves on, I have made Pocket PC versions of my program.
These are for Windows Mobile 2003, 5 and 6. (Note! Not for Smart Phones!)

The program has:
- Safety Factor calculator. You can calculate safety factor on given load and sling.
You can also calculate needed sling capacity if you choose safety factor and load,
or calculate load that you can hang if you choose safety factor and sling.
- Choker hitch allowable load calculator.
- Basket hitch allowable load calculator.
- Resultant calculator.
- multi Point Truss bearings calculator.
- Measurement conversion.
- Wind force calculator
- and adding...

The main functions of my program are three load distribution calculators:
-Bridle; calculates bridle's lengths and forces, with picture and log.
-Truss; calculates trusses forces, CG, angled dead hangs, with picture & log.
-Grid; calculate grid's forces, CG, with picture & log.

Those are the latest, so they don't have save option, yet.

Applications are free to download from my site in exchange for your free membership (after downloading file(s) you can distribute it, but support is available for members only).

Tutorial is in making, until than you can check out this one. It is not for pocket PC, but for desktop application, but the idea is the same.

Zitat von "treibsand"

The sad thing is: the lifts weren't the point of failure...

It seems to me, like the middle section of the canapy (joint in the middle) gave up

Zitat von "treibsand"

Another sad thing: this does'nt seem to be build by a very chaep company or someone without any knowhow.

I don't think so also. I checked the company web sitem they seem to be big...
http://www.icpatlanta.com/

To me, the roof seems good for making shade (Schatten), not for bearing the load...

and now it is good for nothing.

I used to work for ground suppotr company, and we also had some accidents. What was more scarry, the director of the company insisted that we use damaged trusses ("it is missing just a pannel, what could go wrong?"). I was so scared for safety (first for me climbing that roof, and than for serious 'gravity' of the problem), so I left the job...

and thanks for english!

Zitat von "SimonFB"

Ich hoffe die drei sind nicht schwerer verletzt, das konnte ich dme Artikel nicht entnehmen.
Aber dieser Aufbau ist auch ein absolutes no-go. Soviele Fehler auf einmal sieht man sicherlich selten.

google translate: I hope the three are not serious injured, I could not dme article below.
But this building is an absolute no-go. So many mistakes at once, one sees certainly rare.

I think they are ok, as I understand the article.

I am not sure, but I think this is original roof
http://www.beezgetz.com/original_roof.jpg
(not for that event)

and could I ask you to write in English, so we could correspond more easily? Schon Danke!