Local buckling of steel plates in compression is often the limiting design criterion for section design. Slenderness limits for plates, stated in Codes of Practice, dictate the form of section and frame analysis that may be used. These slenderness limits have been evaluated assuming free buckles and may be too conservative when the plate is in contact with a rigid medium, e.g. at the top flange of a composite beam or concrete-filled steel section. The evaluation of slenderness limits for elastic, compact and plastic buckling is complex and involves empirical input. This paper describes a method whereby slenderness limits may be evaluated in a rational way. The method is used to obtain slenderness limits for a variety of sections when the plate is in contact with a rigid medium. Professor H.D. Wright
This paper is intended to provide background information on National Vocational Qualifications (NVQs) as they are likely to affect the Institution of Structural Engineers and, in particular, its role as a qualifying body for the profession of structural engineering. As a general introduction to the topic, I quote the introduction and the fundamental criteria from the Guide to National Vocational Qualifications published by the National Council for Vocational Qualifications (NCVQ) in March 1991. The acronyms ‘NVQ’ and ‘NCVQ’ are but two to digest in tackling this topic; there are also many new terms employed in place of otherwise familiar ones. Annoying as this may be, it provides a common vocabulary for a wide range of different areas of employment covered by NVQs. In this paper, I shall be concentrating attention on the construction industry. B. Simpson
CISC (which now stands for the forum for NVQs/SVQs at professional, managerial and technical levels in planning, construction, property and related engineering services) has drawn up a set of occupational standards for use within the area of their remit. What people do in these areas has been laid out in the form of a map of functions. A ‘function’ is an outcome of a work activity intended to be described independently of the process of achieving it. One’s ability to achieve the required standard of performance at work (i.e. one’s competence) will be measured against performance in relation to these functions. A set of such outcomes will form a National Vocational Qualification (NVQ). Professor I.A. MacLeod
Spectator terrace barriers are widely used to limit crowd pressures and thus prevent injury. Barrier strength requirements, configuration guidelines, test procedures and permitted crowd densities are stated in the Guide to safety at sportsgrounds, known as the ‘green guide’, published by the Home Ofice. The design requirements primarily stem from research following two crowd disasters - Bumden Park, Bolton, 1946, where 33 fatalities occurred on a terrace and at Ibrox Park, Glasgow, 1971, where 66 fatalities occurred on a crowded stairway. More recently, 95 fatalities occurred on a terrace at Hillsborough, Shefield, in April 1989. The most recent version of the ‘green guide’ was published in 1990. J.F. Dickie and G.K. Wanless
Partial underpinning of semidetached houses With reference to previous correspondence (20 April and 18 May), Tom Hill, of Hampton- Upon-Thames, introduces the question of provisions which may be included in house deeds to safeguard owners’ interests where raft foundations are shared: This problem requires provision in the house deeds. The raft foundation causes one house to be structurally dependent on the other, similar to flats where owners share floors. Covenants are required to safeguard the interests of both owners. Verulam