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Culverts - first determine bending moment (tensile surfaces) and reinforce either one of two ways: See hand sketch below - once you know moment and effective depth of tension reinforcement you can design the joint. 1. U-bars coming in from slab and wall and connecting in corner. 2. or, Top/outer bar bent around the joint. 3. Option 3 is to use L-bars at joint, - see sketch below for all three ways you can detail a culvert corner - your engineering judgement is determine which detail best suits your design! Spacing of reinforcement tend to be closer to limit serviceability stress and hence crack width in concrete to <2mm - for reinforcement durability, and to stop water corroding the reinforcement, and to have a watertight structure; Movement joints are tricky in culverts. Make sure the concrete (or cement) selected is ok for, (i) against corrosive soils and (ii) chemicals in (waste) water.

I think we are mixing a lot of things up here.... one must first feel comfortable designing a structure by hand, then rely on software. I will carry on with my previous numbering so you see the whole picture. 4. You must ask yourself, could I design a flat slab concrete structure by hand by determining moment and shear coefficients for continuous slab case for vertical gravity loading. This will give you both shear and moment value. Each CODE has rules for splitting the slab into "column strips" and slab strips" to determine width of slab for each hand calc. Decide which code you are going to use and follow its "design rules" for "flat slabs" / "flat plates". 5. With flat slab structure (no down stand beams) you will always require shear reinforcement in successive perimeters in the slab around the column. The exception would be if your column was say very large in plan size, or you thicken the slab around the column. Again, follow code approach, you should be able to do quick check by hand! 6. Next, how is the lateral stability of the structure achieved - shear walls or lift shaft? This is key as all lateral loads will go to these vertical elements via the floor slab diaphragm, limiting lateral load moments on the column at junction with slab. In earthquake regions i would plan lateral stability system first! 7. PT slabs require specialist PT tendons and grouts, quality control etc. They are often used to "thin" the slab section. They are expensive and require specialist installation. If you have all that (not sure if its economical for two storey building slab, unless it’s very heavily loaded, and has large plan area) then I would now even pursue this option. 8. Instead of PT slab, I would consider down stand beams to cut down slab span. There are various slab types which will span 9m (30'), or a coffered slab (designed same way as flat slab). 9. For your analysis, do not put in the 750mm long cantilevers, and design slab shear around the column. 10. Get the code, then the code handbook, then design. ETABS it seems to me have done a very good selling job in PK! Design is in three steps: Crawling (college and uni studies), then walking (understand all structural concepts and design concepts by hand) and then running (rely on software only when you can judge if the output is in the "correct ballpark", by looking at the results! a. Will span say 7-8m (24'), approx 300mm thick,no beams b. Will span 10m (30'), 600 o/all thick, beams within depth Or a (c) Traditional beam and slab system will suffice. Or (d) if you local expertise available, then use PT slabs (the tendons need to be protected during building life from any damage, say someone drilling a hole into the tendon during building life, and also special techniques are required to demolish PT buildings.

Salam, B/C CR is normally displayed for SMRF for seismic zones 3 and 4. You may check the beam and column section capacities manually and have some idea of the weak beam strong column, detailing rules also help, keep the column sections larger than beam section, keep your beam inside the column width. Cracked versions sometime have some problems. Search the forum for this topic there are many threads for that. here is one.

Time for Pakistan Structural Engineering Profession (& PEC) to look at allowing Eurocodes use? I would like to advocate the use of EUROCODES in Pakistan for a number of reasons: 1. The Eurocodes covers all structural engineering design of elements, i.e. EC0 (basis of design), EC1 (loadings), EC2 (concrete), EC3 (steel), EC4 (composite steel/concrete), EC5 (timber), EC6 (masonry), EC7 (soils/geotechnical), EC8 (Earthquake), & EC9( (aluminium structures); These are adopted in 27 European countries, and also in Turkey, Malaysia, Hong Kong, Singapore etc. They should be used in conjunction with Pakistan Building Code which would be updated to include Pakistan National Determined Parameters. 2. American codes take an empirical approach, whilst Eurocodes are based on structural engineering theory and mechanics! Lot suited to teaching of theory approach in PK universities. I believe Canadian codes are closer to Eurocodes! 3. Pakistan would benefit from extensive research already in circulation on these codes and would be able to move forward in structural engineering t - and using the existing codes as a stepping stone to progress the country’s construction engineering academia and professionals progressing on with their own research etc. Whilst its not easy, I will attempt to lobby/inform the relevant authorities in Pakistan to look into this matter of Eurocodes design of structures in Pakistan. I would like to have the views of fellow structural engineers on the issue? Any thoughts on the matter?

i've just read this topic and i started to search through google. i found this paper . https://www.mdpi.com/2076-3417/6/11/317/htm this is interesting. So, in your project, what is your consideration for choosing this typical of pile (steel piles).