Originally Posted by mechdesign

bulk density of fly ash - 650 ton/m3

I think you need to take a new look at this number. ■

Standards are easily available from your friendly local Association. A textbook on silo design was touted around these forums a couple of years back.

If you have 2 outlets for tubs, the trade name for 'covered' powder tankers, please understand that there may be usually 3 manholes to fill. Manhole covers, hatches, will need to be positioned under the spout, accurately. You will need several markers to shunt the various combinations of tractor and trailer into position. It is obviously unwise to continue loading while shunting. Headroom clearance is another point if you are thinking of a fixed walkway. Besides shunting the vehicle the driver is also responsible for closing the redundant hatches in the interest of no dust emissions. This means climbing up and down a 5+m stairway so that the leading hatch can be closed, then move on to address the subsequent hatches. This cannot be done by a plant operative because the driver alone is responsible for eliminating any emissions from the vehicle for which he is legally liable. So your 200tph/spout probably needs drastic upgrading.

Be careful not to obstruct vehicle workings by placing columns where they will prevent doors opening etc. Drive through working will interfere with the radial dispersion of the columns and you will have unequally loaded circular beams to wrestle and build in the first place.

What wall depth of fill are you expecting from 16m dia x 16m high considering surcharge. This will affect the fill pattern since the inner outlets will take priority.

All in all it's not well considered and you would be far better filling 4 bins.

Selection of the opening is about all this proposal has going for it. Tanker manholes are 20" nozzles with a hinged lid secured by swing bolts and a single safety bolt. ■