a grading analysis somewhat coarser than that shown in Fig. 6. The high content of cellular material led to erratic moisture/density results and very low dry densities in the laboratory.53. The dry density varied between 54 and 60 lbjcu. ft over a range of water content of about 35%, with no clearly defined optimum value, In one way, a material having this characteristic was no bad thing since it could be easily Compacted over a wide range of moisture content and weather conditions. A good sub-base of stronger and less variable material would be required, however, between the formation and the road construction.54. Another interesting point was the breakdown of the coarse lagoon ash under dynamic compaction in the laboratory, the d20 size decreasing from 0.2 mm to 0.095 mm with the uniformity coefficient (d60/d20) increasing from 3.5 to 5.0. 55. It was largely because of the poor compaction results combined with the low increase of strength with time that it was decided to provide bank seats of cementstabilized ash rolled in situ. Crushing tests on 3-in. diameter cylinders of cementstabilized coarse lagoon ash compacted with standard Proctor energy at 33% moisture content and cured in a saturated atmosphere gave the results listed in Table 10.
M r B r i t t and M r CockcroftAlthough in the N-S direction the ground profile is ideal for a three-level scheme, the length available in the E-W direction is restricted by the railway viaduct to the east and by the future M1 junction to the west. Consequently the maximum gradient had to be used throughout the slip roads, causing difficult profile problems at the round-'about, and the eastern junctions with the North Circular Road are much shorter than would have been desirable.96. Brent Cross like most projects involved collaboration not only with the Architect, who should receive full credit for the pleasing appearance achieved in spite of the restrictions imposed by traffic and structural requirements, and with our Clients the Ministry of Transport, but with many other bodies.97. Middlesex County Council and Hendon Borough Council were concerned from the earliest stage and their suggestions considerably influenced the evolution of the design. Five different statutory bodies were involved in alterations to the complex system of pipes and cables, and their programmes had to be co-ordinated with each other and with the Contractor's programme, The Metropolitan Police, the Borough Council (representing local residents) and London Transport (both the management and the busmen's representatives) had to be satisfied in advance with provisions made for traffic throughout the Contract. The assistance of the police in agreeing to temporary restrictions and providing uniformed men to control traffic, was greatly appreciated.98. We would like to put on record the assistance given by all these bodies and also the County Council who accepted considerable complications in carrying out an adjoining road improvement in order to simplify our work in connecting it with the flyover approach, the Borough Council's lighting department who carried out work on existing street lamps as needed, often at short notice, and the drainage department who gave invaluable assistance in identifying and deciding how to deal with the many old and often unrecorded drains which were encountered. 99.We should also like to repair an unfortunate omission in 9 93. The Resident Engineer was also assisted by Mr H. Tanton. M r F. J. Cave, City Engineer, City of Westminster In 1958 I was with the Borough of Hendon. This project was a major construction in a suburban area and raised the usual sort of problems produced when building near houses and near places where there is a great deal of traffic already. Many complaints had been received by the council about the difficulty of access to buses at this intersection.101. I think a compliment is due to the officers of the Ministry of Transport, to Mr Andrew, who was then the County Surveyor of Middlesex, and to the Consulting Engineers for the consultation procedures developed. These developed from experience with the Watford Way Bypass, the Apex Corner roundabout proposals, the dual carriageway proposals for Hendon Way, the proposals for the extension of the M1 to Fiveways Corner and the further extension of...
DiscussionProfessor P. B. Morice (Professor of Civil Engineering, University of Southampton) said that the Author had clearly demonstrated that the general problem of structural design was at present beyond the scope of computers. He too had found this and recently, therefore, he had been considering a more limited aspect of the problem which was: given a general structural geometry, what were the dimensions that led to minimum cost? It was also of interest to know how cost varied with changes from the optimum dimensions. Such a solution made no attempt to provide complete designs but acted rather as an aide memoire to assist in the process of design.76. The first problem he had studied was that of single-storey roofing using twopinned steel portals and purlins for a building of inlinite extent in width and length. For given frame heights, loading, soil properties, and unit costs a simple programme led to the cheapest span and spacing, with a specification of member and footing details, giving costs per square foot very close to those currently accepted. In addition, plots were obtained of the variation of cost with stable designs of different span and spacing, producing what might be called "cost surfaces". A whole system of cost surfaces resulted from different loadings or storey heights.77. The fact that a few hours' programming and a few minutes' machine time could lead to the well-known answer was very satisfactory. It seemed possible to study new structural forms where there had not been many years of practical experience, and where there was no well-known answer to the problem of minimum cost. He believed that that was the case with plywood box beams which he was now investigating.78. The Author had said that new machines were on the whole easier to programme than the old ones. The next generation of machines, Professor Morice believed, would be designed specifically for autocodes, i.e. simplified methods of programming, which the engineer could use himself. A considerable number of civil engineers he knew had already made use of autocode programming with great success. That had avoided the disappointment some engineers had experienced in employing mathematicians as programmers. Confusion frequently seemed to arise owing to the inability of men of different disciplines to communicate sufficiently precisely, resulting in admirable arithmetical solutions to the wrong physical problem. In his experience, except for the preparation of the most general form of programme it was better for the engineer to do the work.79. The Author had asked what should be done for engineering undergraduates during their training. Professor Morice considered it very important that they should have some acquaintance with electronic computing machines and at least realize the scope of their application. In his own department a large proportion of the undergraduates had an opportunity to make use of computers in connexion with project work in their final year, and provided that the computers were regarded as standard apparatus, ...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.