kleinewolf7

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About kleinewolf7

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  • Birthday 12/08/79

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    Ghent, Belgium
  1. Does anyone know if there is a code for calculating a masonry wall with the first (under) row of stones with another (lower) compressive strength ? (p ex to avoid a lineair thermal bridge)
  2. Hi, I wonder if there is any freeware for the design of pilecap of more than 4 piles (in my case 8) based on the strut and tie model (eurocode) , or a theoretical description. Thnx
  3. I'm looking for a suitable stress-strain curve for non-lineair analysis of a concrete section. I know EC2 doesn't allow concrete in tension, but it's for a theoretical algoritm.
  4. Thnx. I won't do much when there is only a mechanical connection, but it's more like a general question. When following EC5 I think : u,inst = u,inst,G + u,inst,Q1 + phi0i . u,inst,Qi u,creep = kdef . u,inst,G + kdef . phi,2,1 . u,inst,Q1 + kdef . phi2,i.u,inst,Qi u,fin = u,inst (CC) + u,creep (QPC) I would calculate (EI),fin (according to annex B) with E/G/K,mean for determing u,inst and E/G/K,mean,fin for determing u,creep. E1 and E2 in annex B can be easily replaced by E,mean,fin (based on kdef for material 1 or 2) but what about Kser ? Because of 2.3.2.2(4) I'd say kdef to determine Kser1 is calculated as 2.sqrt(kdef1.kdef2)... ?
  5. Hi, Does anyone have an example or theoretical literature about the final deflection (u,fin) of a wooden floor (p.ex. beam C24+OSB 18mm ; p.ex. connected with metal screws) How to calculate the influence of creep on Kserv, E-mod ? (how to put annex B of EN1995-1-1 in practice ; how is (EI)ef translated into final deflection?
  6. You can find the example on http://eurocodes.jrc.ec.europa.eu/doc/WS2008/Kristensen_Hansen_2008.pdf
  7. Thx. I agree now :-) And, yes, I would see an imposed load as a different load on every story. But that makes just too many combinations I guess for higher buildings. But that would make the NED for a column on the lowest floor lower, and that just doesn't seem right to me. So, seeing the imposed loads of different stories as a single action would be more logic. But the eurocode doesn't forbid to do otherwise...I guess? So why not? I've seen an example of Kristine Bak-Kristensen and she sees all imposed loads of the same category (on different stories) as a single action (like you suggest) (for combinations for maximum reaction on lowest floor)
  8. I don't follow your opinion here. 3.3.2(2) states that you can't combine psi,0 reduction and alfa,n (there is idd a difference between alfa,a and alfa,n; but for column check alfa,n will do), otherwise you reduce a already reduced value. But 3.3.1(2)P says : when imposed loads act simultaneously with other variable actions (such as wind; snow;...) the total imposed loads shall be considered as a single action. (and thus no psi,0 reduction?)
  9. Thnx for the quick response Reinis. What I'm actually trying to say (for a residential multistory building, phi0=0.7) 1/ there is clause 6.9b in EN1990 to make combinations : Ed = gammaG*Gkj+gammaQ*Qk1+gammaQ*phi,0i*Qki (for i>1) 2/ there is reduction factor alfa,n (clause 6.2 EN1991) alfa,n=(2+(n-2)*phi0)/n If you have to calculate a specific column on the lowest floor; how to make NEd? 1/ NEd = Gd + Q1 + (n-1)*phi0*Qid 2/ NEd = Gd + alfa,n * Qdtot (Qdtot=Q1+sum(Qid)) If you calculate what reduction on Qdtot you have, we come to : 1/ reduction factor = (1 + (n-1)*phi0)/n 2/ alfa,n = (2+(n-2)*phi0)/n Both equations go to 0.7 (=phi0) for n=infinite, but equation (1) is in all cases a lower value; so, more interesting to use. That's the point I'm trying to make (?); why use alfa,n in such a case, if the normal load combination (equation 1 herebove) is more interesting? Remark: Clause 3.3.2(2) states to use phi0 OR alfa,n (not both together)
  10. 6.2.2(2) says that the live load for columns may be reduced with factor alfa,n. For 3 stories, this is 0,9. On the other hand you can 'make' the ULS combinations with gammaG*G + gammaQ*Q1 + gammaQxphi,0*Q1 + gammaQxphi,0*Q2 + ... Can Q1, Q2, etc not be seen as live loads on the different storyfloors? In this way phi,0=0,7 (for residential buildings) gives a greater reduction for lower buildings... Am I right?
  11. In the belgian national annex they say that remark 1 may only be adopted if the client agrees witht this... I think they put it in to simplify the combinations (the combination of the actions 'may' be based on not more than 2 variable actions)
  12. Hello, The only imposed horizontal actions I find in the eurocodes are table 6.11 in EN1991-1-1. In other (older) standards there is sometimes a certain percentage of the verical imposed load that you should consider. Here there isn't? Of course there are the equivalent horizontal loads (equivalent for imperfections; found in EN1992,1993,etc), wind load, earthquake loads, traffic loads (EN1991-2), etc; but not for normal imposed loads? (exemple : steel staircase ?) Thnx
  13. Hello, I have a simple question about calculating the reinforcement in een rectangular concrete column. When the column is simple one-way structure with only a normal force acting in the centre, you can manually or by means of software calculate Az (total reinforcement in z-axis) and Ay (total reinforcement in y-axis) (Y and Z major axes). In that particular case (only N-force, no moments of 1st order); the results are by example Ay=Az=4cm² for a square column of 25x25 cm². Do 4 bars of dia16 suffice? Or can't you count the cornerbars double? In my opinion, again, in this case (NO biaxial bending), you can. Because the only excentricities (and thus moments) that appear are those of ea and e2 (second order excen.) You have to calculate them in both directions, but these cases cannot appear at the same time, so it's a OR - OR reinforcement situation that outcomes...I guess... I don't know if I made myself clear in poor Enlgish...Does anyone have a clue? Thnx
  14. Are there guidelines or articles in which the maximum length/width [m] (or area [m²]) of concrete slabs (used for the inside of a building) is determined? Or a way to model the influence of shrinkage/temperature? I found some values of 50 to 60m, but I found no scientific basis. And what about U or L-shaped slabs? Thnx