ICE - Institution of Civil Engineers - Virtual Library

268 WILLIAIS ON FLOODS IN THE BRISBANE RIVER. [Selected (Puper No. 3130.) " Floods in the Brisbane River; and a System of Predicting their Heights and Times." By CYRUSJOHX RICHARD WILLIAMS, Assoc. M. Inst. C.E. over an area of about 5,200 square miles above Brisbane, and lies generally in a north-west and south-east direction, between latitudes 26" 30' and 28". I t is bounded on all sides by mountain ranges, varying in height between 1,000 feet and 3,000 feet...

(Paper No. 3247.) On some Effects of Land Floods in a' Tidal River." By CYRUS JOHN RICHARD WILLTAMS, Assoc. M. Inst. C.E. IN previous Paper the Author described some of the character .. a istics of floods intheBrisbaneRiver. As asupplementtoit, some notes on the effects of these floods, more particularly in the presentedin thefollowing tidalcompartment of the river, are Paper. The Author'sposition inthelateHarboursand R.ivers Department, as AssistantEngineer, i n charge of the Brisbane River works, involving, as i t did, the frequent examinationof tllc river-channels, andthe observation and recording of changes therein, and his subsequent position in the Water-supply Department, afforded himexceptionalopportunities forobserving the effects of floods...

Papers.] WILLIAMS ON ARTESIAN SYSTEM OF QUEENSLAND. 315 (Paper No. 3490.) "The Artesian System of Western Queensland." By CYRUS JOHN RICHARD WILLIAMS, M. Inst. C.E. THEmain artesian water-bearing beds of Queensland consist of a series of strata extending from their outcropping edges along the western slope of the mainwater-shed on the east side, to outcrops of primary rock on the west and north, and perhaps to on the south-west. On thelatter the Great Australian Bight pointthereisstill some difference of opinion,although itis certain that they extend in that direction under the borders of Queensland, beyond which the Author's experience does not range...

THE INSTITUTION 0Y -. . . SESSION 1929-1930.-PAltT 2. MINUTES O F PROCEEDINGS. 25 February, 1930. WILLIAM WYLIE GRIERSON, C.B.E., President, in the Chair. The following Papers were submitted for discussion, and, on the motion of the President, the thanksof The Institution were accorded to the Authors. (Payer No. 4694.) " The Development of Lyttelton Harbour, New Zealand." By CYRUS JOHN RICHARD WILLIAMS, Inst. C.E. M. PORT LYTTELTON, originally called Port Cooper, is an arm of the sea on the northern side of Banks peninsula on the east coast of the southisland of New Zealand, inlatitude 43" 36' 42" south and longitude 172" 44' 17" east...

6972 DISCUSSION Rock excavation and specification trials for the Lancashire-Yorkshire motorway, Yorkshire (West Riding) section H. WlLLlAMS & J. N. STOTHARD M r R. C . S. Walters, Partner, Robert Lapworth and Partners The Authors' Paper describes in the main the requirements for a stable embankment reaching a maximum height of 215 ft for thedual role of motorway embankment and dam. The experiments, however, were concerned with ascertaining the best way of compacting this depth of fill to ensure the least settlement for thesix-lane motorway...

Preloading and stage-loading operations were carried out at an industrial plant site in Trinidad, which is underlain by about 10 m of lightly overconsolidated recent sediments. A series of drained stress controlled triaxial tests and oedometer tests were carried out to define the yield envelope for these deposits. Filling of large diameter water storage tanks was controlled by computing the effective stress paths during loading and relating the effective stress states to the yield envelope. The objective of this procedure was to prevent overstressing of large zones within the foundation soils and thereby to minimize lateral deformations which would result in excessive total and differential settlements. This objective was achieved as indicated by the relatively small 40 mm lateral deformations which were associated with up to 300 mm of vertical settlement. Settlement profiles across the tanks were also very uniform. The effective stress path yield envelope approach was also used to explain the significant decrease in porewater pressure dissipation rate which occurred about three months following completion of a preload fill. The change in dissipation rate occurred when the effective stress state reached the yield envelope and yielding occurred. During first filling of the tanks, the porewater pressure response within the recent sediments was bilinear. Remote from drainage boundaries, the initial response was approximately elastic. On further loading, the response increased and the porewater pressure was approximately equal to the applied surface loading. The locus of effective stress states associated with the change in porewater pressure response appears to define an elastic envelope within the yield envelope. The upper portion of the elastic envelope coincides with the K ₀ stress ratio for the deposits in a normally consolidated state.

Des opérations de préchargement et de chargement par étapes ont été effectuées sur un site de Trinidad (Antilles), où se trouvent à peu près 10 m de sédiments récents légèrement surconsolidés. Une série d'essais triaxiaux à contrainte contrôlée et avec drainage et d'essais oedomètriques a été effectuée pour définir l'enveloppe d'écoulement de ces dépôts. Le remplissage de réservoirs d'eau de grand diamètre a été contrôlé par moyen de calculer les chemins effectifs de contrainte pendant le chargement, après quoi on a mis les états effectifs de contrainte en rapport avec l'enveloppe d'écoulement. Le but visé était d'empêcher le surchargement de grandes zones dans les sols de fondation et de minimiser de la sorte les déformations latérales qui produiraient des affaissements totaux et différentiels excessifs. Ce but a été atteint comme l'indiquent les déformations latérales relativement réduites, observées avec jusqu'à 300 mm de tassement vertical. Les profils de tassement à travers les réservoirs étaient aussi très uniformes. La méthode de l'enveloppe d'écoulement du chemin de contrainte effecti a été employée aussi pour expliquer la diminution de la vitesse de dissipation appréciable de la pression de l'eau interstitielle qui a eu lieu environ trois mois après la fin d'un remblayage de préchargement. Le changement dans la vitesse de dissipation s'est produit lorsque l'état effectif de contrainte a atteint l'enveloppe d'écoulement et l'affaissement a eu lieu. Au cours du premier remplissage des réservoirs la réponse de la pression de l'eau interstitielle dans les sédiments récents était bilinéaire. A une distance éloignée des limites de drainage la réponse initiale était approximativement élastique. Au fur et à mesure que le chargement continuait, la réponse de la pression de l'eau interstitielle s'est augmentée, étant approximativement égale au chargement superficiel appliqué. Le lieu des états effectifs de contrainte, associée à un changement dans la réponse de la pression de l'eau interstitielle paraît définir une enveloppe à l'intérieur de l'enveloppe d'écoulement. La partie supérieure de l'enveloppe élastique coincide avec le rapport de contrainte K ₀ pour les dépôts dans un état normalement consolidé.

Paper No. 6425 DESIGN, FABRICATION, AND ERECTION GANGA OF MOKAMEH, INDIA bY BRIDGE, Sidney Turley, BSc., A.M.I.C.E. A Senior Engineer, Messrs Freeman, Fox & Partners, Consulting Engineers Sadashiv Gangadhar Savarkar Agent, The Hindustan Construction Company John Williams Agent, Messrs Braithwaite, Bum & Jessop Construction Co. Ltd and Rathlin John Clinton Tweed, M.A.(Cantab.), M.I.C.E. Braithwaite & Co. Engineers, Ltd (loaned to The Braithwaite, Bum & Jessop Construction Co...

172 CORRESPONDENCE ON EARTH-PRESSURE ON WALLS [~inutes of Correspondence. 30. Ash. Mr. WILFRID ASH observed that the Commissioners for the C. decades, had in hand Port of Calcutta had, during the last two dock accommodat,ion. The number of extensions of their wet berths in the existingKidderpore docks had been increased, and the first stage of t,he new King George's dock was now approaching completion. I n both those works monolith construction forthe quay-walls had been adopted, on account of the character of the strata to be penetrated...

204 TESTING OF RAILS. Mr. J. PRICE observed that the extreme difficulty in obtaining good rails, no matter how carefully the specification was drawn up, had led him to the consideration of a machine fur the purpose of testingrails.Hehad found thatrails whenfrom the same maker and of the same price were often very different in quality. He didnotsay that was thefault of the manufacturers, but he thought they required to be instructed how t o apply a test whereby it could be ascertained what was the most serviceable quality of iron fur rails and what was the best modeof manufacturing them...

86 CORRESPONDENCE ON HARBOUR WORKS. [MinUtes of Correspondenoe. Mr. Cullen. Mr. E. $. CULLEN remarked that Mr. Brist,ow's Paper would be read with great interest by harbour-engineers, as it afforded details of work brought to successful completion in the face of great difficulties. The difficulties attendant upon the use of a floating pipe-line in open water could only fully be realized byactual experience ; Mr. Bristow and those associated with him must have had many anxious moments and discouraging experiences before a. pipe-line adequate to the physical condit,ions was developed...