Page 24 - Minutes of Proceedings of Civil Engineers Vol CXCV 1913-14 Part 3 Correspondence
P. 24
l'rrrnotlings.l TIIE "WHITE STAR" DOCK AT SOUTIIAMPTON. 139 ru'nll wns built, for the purpose o[ constructing a new roed running trrr. olive. lrrlrrllol with and cbse to the w*ll-face and at a somewlnt lowsr l,'1',';. The wall beglrr to heel over, causirrg the batter of I in 12 to ,lrulppcilr arrd the face to corne to the vorticnl. I-le overc:rttte tlrrr rlillicrrlty by introducing blocks of brickwork at intervals at the rrrxi,lu of thetop of the wnll antl :r,ncholiug then by long bolts ;,rr.rsirrg liglrt, through the block and tho rvall, and he lurd found I lrrr.t plrr,rr quite effbctive. f\l r'. H. OeRrwtrcur Ilnru observed that the groa,t depth of moderrr l\rr. Reid. rvau renderirrg the provision of adequate harbour accommoda- ^lrilrs l,iotr u,vcry serioustluestion. IIe believed thecorrstructionof abertlt 'l() fcct in depth at, low wlter of ordinary spring-tides was unique, nrrrl the relson why this depth was decided upon had not been trrrrrle clear. According to Fig. 12, Plate 2, the "Olympic" drew il'l feet 6 inches. If the a,dditional depth of the berth was intended l,o provide for future deepening of ships, the vory large margin it gruvo had beon provided at considerable expense *'hen the cost of the lxrttorn 5 feet of the walls was tak€n into account. IIe knew of rro ship drawing rnore tban 35 feet, and it was very unlikely that rrrr"vu,l u,rchitects would make ar,ny serious increase on this, even if it rvrrro fsund that with large ships speed could be attainerl only rvhen I,lruy rvere of deep draught. There must be a liurit of depth, due Lo the natural form:rtion of nrost of the harbours and also of rrrnsidetable stretches of water, such as the North Sea, in wlrich, ovtlr some areas, it would be dillicult for a ship drawing 35 feot to I'c nrr,vigated safely at low water, No doubt, it was an advantage l,o be able to berth ships like the " Olympic " immediately on their rlr'r'ival, and for this reason a tidnl berth had many advantages, rvhile for the construction of a single berth it would no doubt be nrore economical to make it tidal than to construct an enclosed wet ,krck, such as those which existed in London and Liverpool; but if rr, considerable length of wharf had to be provided, an enclosed basin *'ould be more economical, because a lower wall would suffice where tlrere was not tho range of tide. The l3 feet at the bottom of the wall was the most costly part of it. IIe was glad to see that, l,lro Author had had the courage to stato in the Appendix his rrr,lculntions for the stability of the quay-walls. Some of the 1r:rlticulars were not quite easy to follow, and Mr. Reid could not rrrrderstand why, having adopted one portion of llankine's formula, t,he Author had not adopted the other to give the resistance to moving rlue to the material in front of the toe of the wall. It would be :rdvantcgeous if the Author would indicate how the calculation of 16'3 tons resistance, due to the slope of tho foundation, had been
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