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Rasheed, If the only problem you are asking about is how to anchor the dowels, you may contact Hilti (as you have already been correctly advised by others) for necessary advice as well as execution of job. It is not a new technique, and is being commonly used all over the world, in connection with strengthening and retrofit of concrete structures. There is no harm in using it, provided it is designed and executed by a specialist firm (like the one mentioned above). You should however be careful that by relocation of column, column footing will become a bit eccentric, and may require rechecking to see it remains sufficient for the new situation or not. However, if you need a bit detailed advice, you will have to share some more details regarding your structure and extent of problem, e.g., - What type of structure it is? All RCC or partially concrete and partially structural steel? in what proportions? -Total number of storeys, - upto which level work has completed? - what is the actual bay spacing in both direction? - how many columns are causing problem? - What other options you are thinking of? Regards

Hi guys just to discuss with you my understanding of crack widths in Environmental structures according to ACI. --------------------------- Normal structures --------------------------- 1. ACI 318-95 based on statistical method of Gergely & Lutz 1968 limits Z based on exposure. We are calculating crack widths here. (Normal structures) 2. ACI 318-99 proposed limiting the spacing and removed actually calculating the width and also removed the exposure conditions. For example for beams and one-way slabs s (in) = 540/fs -2.5cc or in other words limiting the fs=0.6fy (For normal structures) 3. ACI 224R-01 references method 1 and 2 above and 3 european codes. The most confusing part is the table in which Nawy suggests 0.1mm crack width for water-tight structures. The whole document is for normal structures except this line. And people are following this line and refer to this document for water tight structures. I mean its just a suggestion and by the way this method 1 is obsolete now since ACI 318-99 (see point 2 above). --------------------------- Water tight structures --------------------------- 1. ACI 318-08 states clearly that for watertight structures ACI 350-06 codes should be used. 2. ACI 224.4R-13 also specifically states that for watertight structures walls in section 7.4, we should use ACI 350-06. 3. ACI 350-06 for water tight structures does not recommend calculating a number for crack width but rather limiting max steel stress in bars to be 20k ksi or fs=0.33fy for normal conditions. --------------------------------------------------------------------------------------------------------- To sum it up, Philosophy of crack width control is not to calculate probable crack widths but to limit the max stress in steel bars. For normal structures: fs=0.6fy and for water tight structures fs=0.33fy

Dear please make sure first that the minimum ratios you put are more than the source from FEM See SAFE help: Minimum Reinforcing Ratio Used for Cracking Analysis edit boxes. Minimum Reinforcing Ratio Used for Cracking Analysis edit box. Use this edit box to specify the minimum ratio to be applied to reinforcing during cracking analysis. This ratio applies regardless of the option selected for the source of the reinforcement specification (see three preceding bullet items). However, the program will use the largest minimum ratio. That is, if the minimum ratio specified here is lower than the ratio specified as part of any of the source options, the program will not use this value. So first check what is the reinforcement you are getting at strength level from FEM. May be it is more than T12@20cm which you are applying for cracking analysis. Please confirm this first!

This is anchorage to concrete problem (i think, other please confirm) There are many industry post-installed anchors companies like Hilti which provide their own software to calculate these things. Check on Hilti website.

Well explained by Mr, Waseem. The first type of Non-Linearity, the Geometric Non-Linearity can easily be incorporated into the structural model. Adding Material Non-linearity is quite difficult. Even there is no code which provides this method. There are many guidelines which normally Structural Engineers follow to add these geometric non linearity. The parameters given in the code are basically derived by considering these non linearities but these parameters do not give 100 percent reliable results, because everything depends upon the shape of structure. The code mostly covers the buildings which has symmetric shape. For example in case of Wind if the structure is not symmetrical or rectangular in shape we can not use the code based factors with 100 percent reliability. Thanks Muneeb