Capacity of Permanent Caisson Foundation Capacity of Permanent Caisson Foundation Kpaudel (Geotechnical) (OP) 1 Jul 16 06:11 Simply press some words with your opinion, is 850 kPa of bearing capacity with FoS of 3, achievable for 10 m dia 20 m deep caisson rest on medium dense sand with SPT N 30? RE: Capacity of Permanent Caisson Foundation EireChch (Geotechnical) 1 Jul 16 10:45 10m dia? Surely a mistake? my apologies, I thought caisson referred to a bored pile and I havnt seen a bored pile 10m in dia. Anywasy - more to the point, i agree, what are you building ? RE: Capacity of Permanent Caisson Foundation BUGGAR (Structural) 1 Jul 16 14:33 We did some 40 ft x 60 ft floating concrete caissons so why not 10m? My opinion must first be fed by my curiosity. What are you building? RE: Capacity of Permanent Caisson Foundation Kpaudel (Geotechnical) (OP) 1 Jul 16 15:21 Dear EireChch, Yes it's 10 m dia well/caisson for bridge foundation. This one is reference for you https://en.m.wikipedia.org/wiki/Caisson_(engineeri...) Yes Buggar we are going to construct bridge. RE: Capacity of Permanent Caisson Foundation oldestguy (Geotechnical) 1 Jul 16 15:44 I'd look more at figuring expected settlement as controlling design. RE: Capacity of Permanent Caisson Foundation LRJ (Civil/Environmental) 2 Jul 16 06:11 Agreed that settlement is likely to dominate design. Scour is likely to be a further issue. RE: Capacity of Permanent Caisson Foundation hokie66 (Structural) 2 Jul 16 07:04 850 kPa is a lot of load on sand. But I agree with others that settlement is what matters. What do you know about how far down the sand layer goes, and what is underneath? When you say 850 with a FS of 3, do you mean 850 is the service load bearing pressure? RE: Capacity of Permanent Caisson Foundation BUGGAR (Structural) 2 Jul 16 13:37 Are you excavating overburden soils for the caisson? Caisson details? Yours is large enough that it is likely cellular. Will the cells be weighted? Sounds very interesting but very vague.