Computer Aided Blog

Cu ocazia celei de a XIX-a Conferinţa Naţionala A.I.C.P.S, o mica parte din echipa Altiscad Software va fi prezenta la standul cu acelasi nume, ocazie cu care vom prezenta oferta speciala pentru membrii AICPS:

Robot Structural Analysis Professional 2010 (-25%) + cadou laptop Dell si Altiscad Optimizer

AutoCAD Revit Structure Suite 2010 + Altiscad Intellishape

Vom fi prezenti deasemenea si prin salile conferintelor cu aparatul de fotografiat la noi, incercand sa prindem din tainele noilor generatii de reglementari in constructii.

Va asteptam cu solutii de proiectare complete.

As we all know “Autodesk Robot Structural Analysis” is a powerful and very useful tool of civil engineers. Thanks to his tools and very intuitive interface even a beginner can use it. But as I will present RSA can be useful not only for civil engineer.

Thanks to possibilities of checking and studying stresses, and others important results, RSA can be use also in other domain of engineering.

An example from live.

Calculation of steel beam which is a part of whole crane system.

General view of steel beam.

(click on picture to enlarge)

Presented beam is a part of hole crane structure,  it is not a typical civil engineering element. On the top plate, we have two moving loads. Loads are representing wheels of main crane part.

Thanks to possibility of study stresses in element we are able to check if adopted solution of beam is correct. If shape of element behave correctly at a given load. By using “Maps of stresses” , in a very easy way we are able to see whether the boundaries of stresses are not exceeded.

Maps of stresses.

(click on picture to enlarge)

Not only stresses in element can be study. RSA is giving to us a possibility of checking displacements. Results which are very important in structures, where all tolerances should be quite small.

By selecting the worse position of forces,  we can see in what way our beam is behaving. How big is displacement.

Displacements.

(click on picture to enlarge)

By checking the displacement, we will know if  tolerances are within acceptable limits.

On that small example we see that “Robot Structural Analysis“, can be use with great success in others engineering domains.

(eng. Damian Fordonski)

As we all know new and existing buildings have to have energetic certificate. But looking on the buildings You can be sure that most of them will have very high level of energy consumption. Correct calculated thermal resistance of construction elements,  it’s in fact half of the success to achieve a good, healthy and ecological house.  By a good thermal design we can reduce total cost of  maintaining  house. Money that normally we would have to spend for heating up and cooling down house can be spend on the other things.  What is then the reason of such a high energy consumption?  Well the answer is not so simple. Probably most of projects are made without any calculation of thermal isolation. Romanian norm C107/2-05 is giving us a minimal requirements for a thermal resistance “R’_min .” of building elements.  According to C107/2-05  for  exterior walls R’min=1,40 m^2K/W,  that is giving coefficient of heat transmission U=1/R=0,71 W/(m^2*K). Interesting it’s what differences we have in typical coefficient of heat transmission for a wall build form concrete or B.C.A. The most popular construction materials.

1. Concrete d=20 cm - R= 0,12 m^2K/W; U=8,33W/(m^2*K)
2. B.C.A. d=24cm      - R=1,5 m^2K/W; U=0,66W/(m^2*K)

That simple example is presenting significant difference in heat transmission between those two materials. But, if B.C.A can be use without any additional thermal protection, the concrete have to be always in addition, isolated to respect norm.

Nevertheless, in my personal opinion, require thermal resistance R’min given by C107/2-05 norm is to low,  putting buildings in Romania in worse position to compare with other buildings in Central Europe, as less energy efficient.  In my expiriance with polish thermal insulation standarts, in which, this same coefficient for a buildings exterior walls, with inside temperature Ti>16 C, is equal Rmin=3,33 m^2K/W and U=0,3 W/(m^2*K). Such a difference is giving significant advantage in a fight for a future costumer.

As an attraction, to compare how different materials can have influence on thermal isolation and energy saves please look on the picture below:

1-polyester 2-wood 3-brick 4-concrete 5-stone

All those walls have the same thermal resistance R=0,25 m^2K/W.

As we see size doesn’t matter.

(ing. Damian Fordonski)