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Dear Eng.mhdhamood Please see following link from Csi https://wiki.csiamerica.com/display/safe/Design+FAQ#DesignFAQ-Whyareresultsdistortedwhenstripandlocalaxesdonotalign? Text from above link Why are results distorted when strip and local axes do not align? Extended Question: When strip direction does not align with the local axis of meshed objects, results are inconsistent. How does SAFE compute forces? Answer: When design strips do not align with the area axis, forces are transformed to coordinate with the strip axis. If results become distorted, rotate the area axis such that it is parallel to the strip axis. Regards https://sa.linkedin.com/in/mjnasar

Direct Design Method (DDM) is the preferable method for designing the conventional two way slab system and other floor system like flat slabs and flat plate slab system. The ACI coefficient method is declared obsolete because the end results are more conservation (more factor of safety). However, still this ACI method is commonly used in most of the design offices for designing two way slab system. NOTE: ACI coefficient method is not used for designing flat slab or flat plate slab system.

Reinforcement's effect is normally neglecting while calculating the elastic modulus of concrete. It is the only function of the compressive strength of concrete: 57000 x sqrt(f'c) as per ACI 318 in feet-pound system.

pleGood day ; To the expert engineers especially in finite element analysis ; When I have a raft or slab with an irregular shape like the one in the photo attached, I wonder about some points which i need your help: 1. The default local coordinates of the raft/slab are the same as for global coordinates, so when I draw the design strips, shall it be in the same direction of local coordinates or i can draw any design strips in any direction ? 2. If I draw only design strips parallel to the local coordinates theni have to put the steel reinfocement in a way that hard to excute on site since there are areas which have columns in an inclined direction. 3. to solve this issue I think we can draw for some areas the design strips parallel to the local coordinates and for other inclined areas we can draw an inclined design stripps ? Do you agree?

Muneeb, Before I reply the question, I just want to confirm that by water proofing did you mean water reducing? if yes, then GGBS can reduce the amount of water required to achieve given concrete strength. Anyway, if you didn't mean that then please see the response below. Generally these questions should be refereed to the company providing the concrete mix design. Ask the concrete mix design company (or ask your contractor to get this answer for you) if the mix design being provided have equivalent water proofing property) as that provided by the admixture. You can provide them the admixture data sheet so they can do they comparison and let you know. I am not aware of any property of concrete that directly measures waterproofness. However, you might be able to establish co-relation if durability properties achieved are same with GGBS as with admixture. Thanks.

I am trying to find you an example. Meanwhile, if you have a round HSS, its fair to find the resultant moment (Mur = Square Root[ (Mux)^2 + (Muy)^2 ]) and improvise on Design Guide 1 example. I will post something as soon as I come across. Thanks.

The question is answered because the discussions are about what kind of torsion a beam can experience and what to do when that happens. As per the discussion even for cases where there is compatibility torsion, even if you don't provide any reinforcement, the moment gets re-distributed. Considering that, for your case of plinth beam that has zero torsion in first place, providing additional just in case rebars aren't doing anything. There is no minimum torsional reinforcement that you have to provide. It should be clear from discussion on compatibility and equilibrium torsion. Anyway, Canadian Code has a requirement for Skin Reinforcement for deep member. The requirement is to limit the formation of flexural cracks The requirement can be found in CSA A23.3-04. I can add some information there but it is not related to torsion and would be off topic. Similarly, ACI requires skin reinforcement on the tension half of beams greater than 36" deep. See 10.6.7 in ACI 318-02. On the same, professional engineers can do anything if their “judgement justifies” that. From diagonal Renata at slab ends to double meshed (full top and bottom reinforcement) on slabs to counter shrinkage, to crazy masonry detailing are things you will notice. None of this is wrong as long as it can be justified. Thanks.

Surendra, Please see this: Thanks.

The quick method to check weather the design of slender column is fine or need to increase the column size are as follows; 1- In order to get the moments along column height accurately, divide the column into 2 or 3 segments. 2- Apply modifier. 3- Activate the P-Delta option from define menu. 4- Run the analysis and design with P-Delta and check the Non sway magnification factor i.e. delta(ns) in design summary of the column (see the pic attached). This delta(ns) must be less than 1.4. If this exceeds the limit of 1.4, increase the column size otherwise the column design is OK. Correction by seniors in my above steps will be highly appreciated.

If you set loading type as nonlinear and set the load application control as displacement, then check if you are able to get convergence in your model. I tried to model material nonlinearity of RCC in a different context, I couldn't get the desired result in SAP 2000.

I will add some more, once you are working out the forces within the tank you have to find out the impuslive forces due to seismic action and the height of the mass above the base of steel tank. You can work out the moments against that moment arm for the concrete structure and at the base slab. Just corss check the forces against the hoop tension generated in case of a circular tank.

You need to consult ACI 313-16. Ensiled material load to be treated as live load

I was browsing through my archives are noticed a bunch of articles written by NICEE (National Information Centre of Earthquake Engineering (NICEE) was established in IIT Kanpur with the mandate to empower all stakeholders in the building industry in seismic safety towards ensuring an earthquake resistant built environment. NICEE maintains and disseminates information resources on Earthquake Engineering. It undertakes community outreach activities aimed at mitigation of earthquake disasters. NICEE’s target audience includes professionals, academics and all others with an interest in and concern for seismic safety). The articles are free to publish as long as original content stays unchanged. These articles are good for fresh structural engineers and Civil/ Structural Engineering Students. The best thing about them is that they are only 2 pages and full of images. It literally takes less than 5 min to go through each. EQTip19.pdf EQTip20.pdf How architectural features effect buildings.pdf How buildings twist during earthquakes.pdf How do Beam-Column Joints in RC Buildings Resist Earthquakes.pdf How do Brick Masonry behave during Earthquake.pdf How do Columns in RC Buildings Resist Earthquakes.pdf How do Earthquake Affect Reinforced Concrete Buildings.pdf How Flexibility of Buildings affect their earthquake response.pdf How the ground shakes.pdf How to make building ductile for Good Seismic Performace.pdf How to make Stone Masonry Buildings Earthquake Resistant.pdf How to Reduce Earthquake Effects on Buildings.pdf What are magnitudes and intensity.pdf What are seismic effects on structures.pdf What causes earthquake.pdf What is seismic design philosophy of Buildings.pdf Why are Buildings with Shear Walls Preferred in Seismic Regions.pdf Why are horizontal bands necessary in masonry buildings.pdf Why are Open Ground Storey Buildings Vulnerable in Earthquakes.pdf Why are Short Columns more Damaged During Earthquake.pdf Why is vertical reinforcement required in masonry buildings.pdf Why should Masonry Buildings have simple Structural Configuration.pdf

this book also useful NED research paper https://www.academia.edu/8983144/A_Practical_Guide_to_Nonlinear_Static_Analysis_of_Reinforced_Concrete_Buildings_with_Masonry_Infill_Walls