Page 20 - Minutes of Proceedings of Civil Engineers Vol CXCV 1913-14 Part 3 Correspondence
P. 20
('WHITE l'r,,ceedings.l THE STAn" DoCK AT SOUTTIAMPToN. 135 lrolo rgainst the fender, instead of permitting the load to be dis- trr. rrnnter. lrilrrrted ov€r as la,rgo a part of tho surfl,ce {ls was possible. IIe ,',rrrsirlered that wnlls ought to be built in such n mnnner as to lontler it impossible for a vessel to bear rgainst the wall below the lrrvcl of low wtter, where nobody could ses whzrt was happening nrr(l where the landing edges of the vessel's plates'lvere sure to be ,'lrrr,fod u,nd worn ariliry. The face of the wall should be plumb, and l,lro portion tbove low water should oversail in such a mrrrner ils Lo pr'oject beyond the line of the part below low rvlter. He woukl srrggest thlt, where the conditions pelnritted, solid dock-walls should lxr abl,ndorred altogebher in favour of piers and l,r'ches. In rnnny r::rscs, though not in all, this would retluce the first cost, while there ruuld be no question as to the rdtlitionnl safety drrring construction, :rrrd as to elimination of the risk of settlement of the filling behind t,lre walls, wlrich was justly legarded by the Author as so serious as to lead him to rrdopt the temporary expedient of covering his quays, lrutrveen the sheds and the btck of the coping of the wtll, with tirnber decking. Mr. Ilunter feared that in the course of a, few ycrrrs this expedisnt would :r, di*rstrous e{Iect rrpon the appear- :rnce of the works. Solid dock-walls were in most erses extravrrga,nt, lrcciluso such wl,lls nlrst be constmcted in thc dry, l,nd therefole rrrnst be treated as retaining-wrlls which were subject€d during the lreriod of their construction to stresses which theywould never htve to withstand when the wnter hld been :rdmittetl into the dock. 'Ihe pier-nnd-arch construct,iorr wrw particularly suiterble for such a cnse as the Whibe Stu,r dock, rvhero the piers nntl the foundations <-rf the sheds uriglrt have becn combined in one structure, witLr :r.dvnntrge to both. The peculirr,r' design of the hook bollards whiclr lratl been fitted into the coping of the dock-rvnlls rvts worthy of rrttention. So far l,s Mr, Ilunter's acquaintance with bollards of tlris type went, the design was entirely original, and if tho Author's lrcrsorral and practical a,cquaintanco with the business of nrooring grel,t Atlantic liners had not been so well krrown, it might have been supposed th:r,t the design of the bollard lud been cvolved by some one whoso view was that such vessels were moored from ono of thoir upper decks, and that it wts desirable to secure the vessel to the bollards in such a manner a,s to keep her from rising during the period of flood-tide. Mr. D. C. Ltrtcn considered that engineers who had been Mr. Leitch. responsible for simila,r works would appreciate the dilficulties and nnxieties which attended the sinking, in ground such as that described, of deep and wiile foundation-trenches, The Author was to be congratulated on his successful handling of the very serious
   15   16   17   18   19   20   21   22   23   24   25