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

l'r,r,nulirrgs.l TIID "WIIITE STAB" DocK AT SOUTIIAMPToN. 129 lrnlirt,o it wes lowered into the water. From experiments he had Ur. Coulchor. rrrn,lo with settlings " he had found that after several months' if " rr,rl, romoved, they became very tough, and would resist the scouring 'rr'l,ion of sea-rilaves to a remarkable degree. 'Was there, in the ,,l,lol work at Southampton, sufficient evidence to show that it was ,,lfo to uso lean concretes such as the 8-to-1 used in the recently- quay-walls, in positions similarly exposed to the action ',rn$tructed ,'l' xon-water of considerable depth ? IIis own experience suggested I lrtb, unless suoh concrete had been Fi.s. 19, rrrrulered impervious by the adop- l,ion of a facing of rich concrete, l,lrc sea-water might sooner or later up disintegration affecting more ',r,t, ,rr less the whole structure. At llrrckie, where he was engaged in srrperintending the construction of I r:r,r'bour-extensions, e good example ,r[ defective concrete work might lro seen in the old harbour, con- structed about 35 years ago. The rr':rlls hacl cracked and bulged and in many ploces the face of the con- clete had fallen completely away. lle had recently had to repair a portion of the old north pier whose l':rce had fa,llen into the harbour. 'ilris particular place was on the lrrrbour side .of the pier near the lrnrbour-entrance and &t a par.t not srrbjected to heavy wav€-action. The damage extended from cope- lcvel to about 1l . feet below it, that was, from about half-tide level n0tg. Vsual nlpFng !tr@gaeaLs up to 5 feet above II.W.O.S.T., wialv rcpe lry @l n lu V;, nnd the concrete appeared to be thoroughly decomposed and disintegrated. Ee had sent samples of this concrete to Mr. D. B. Butler, Assoc. M. fnst. C.8., for analysis nnd report, and with results of which the following was a short summary:- Sam1ile lVo. 1. Taken from the original face of the wall. ,, ffo. 2. Taken from 3 to 4 feet insido face of wall. Roth samples were taken from the work at about high-water level of ordinary spring-tides. [rnr rxsr. a.E. yoL, cxcv.]