Page 4 - Minutes of Proceedings of Civil Engineers Vol CXCV 1913-14 Part 3 Correspondence

lrlr,rulings.l THE " wIrITE STAR " DocK AT souTnaMPToN. 119 'rlrun(l the piles, as.he considered that such a, jetty should beMr.Biuos. ,rr rrrsilicnt as possible. The momentum of a moclern ship striking lrr',rvily against sucb a structure could be absorbed satisfactorily only tl l,lrrr iotty as a rvhole "breathed" to the blorv. A rigid monolithic ,rl1'111r[,111's invited trouble both to tho ship and to tho jetty. He llr,l lrnrl experience at a lock entrance rvith a dolphin consisting r rnonolith of rnass concreto 21 feet in diameter, surmountetl ',1' Iry n bonnet of heavy timberwork. Withiu 5 years the concretc rrrorrolith was frnctured just belorv the bed of the river, and the ,|,'lplrin becnme a source of danger and had to be replaced. It ru',rrrltl be of interest to knorv the total cost of the 'works described l,t, thc Author. 'I'he time taken to cnruy out the contlnct, apparently r,r,'rxrrlcd 5 years, which seemed to be longer than necessary. I\tr. G. Wour,rn Btpxex considered that the toe in front of the Mr' Brenan. ,l,x,l<-rvalls and the downward slope of the bnse were much to be r,rnunended in dealing 'with such a foundation, and were in full rrcr.oltl with the theoly of stability. The resulLtnt 'rveiglrt of thc rrlroltr rvas thus kept well within the bnse, and the danger of r,,ftcnerl matelial being forced up below tho base by back-pressule rrrls grcatly reduced. Sinrilarly the yieldiug of the subsoil at the Irtnt rvils arrestetl by the projection of the toe, This form of rrrnstrrrction hrd Iong been atlopted in reinforced-concrete retaining- ru';rlls. At the rirme time, it seemed to him thnt the weight nnd lrrrlli of the rvall rverc super-nbundant for its purpose. Given the l'rrll dimensious shown in the base-block of concrete ns necessary to rrrtrct this case, rvould not a lighter 5h'11sf,urg-snch as separnte front rrrrrl r.crll concrete u'alls. built rrp from the foundntion block of r.oncl'ete, and connected by cross walls filled betll'een rvith healting ,l' Iruilt rubble pncked rvith clty nnd sand in the interstices-lnre lrrcn more economical, and better on the infelior foun