A common means of forming a rigid joint between universal beam and column sections is to weld an end-plate to the beam end and then to bolt to the column flanges. Tests on models of he tension region of beam-column moment connections joined in this manner, and also complete joints, have shown that the behaviour of the beam tension flange force upon the end-plate and column flanges can be represented by isolated T-stubs. Typical modes of failure for this type ofjoint are discussed relative to experimental observations, and the yield-line method is then used to predict column flange and end-plate flexural yield loads. Good agreement was achieved with test results. A limit state design method is proposed for extended end-plate joints having four bolts in the tension region, and from which stiffening requirements can be readily assessed where necessary. J.A. Packer and L.J. Morris
Mr. Barron: The authors say that the terms of the contract should conveniently be those of a building contract which would be most appropriate for the much more costly superstructure. They actually used the RIBA conditions, more usually referred to as the JCT standard form. They could have also or alternatively used the ICE conditions modified for work with high architectural content. Did the JCT form prove to be as convenient as expected?
The large cooling towers being built today are quite exceptional structures being, in proportion, considerably thinner than an egg shell but approaching 200m in height and lOOm in diameter. Practice has outstripped both theory and research and there are wide national differences in approach. The relevant design parameters are reviewed, namely, wind pressure, including wind induced vibrations, thermal gradient, self-weight and moments in the shell. Comparative calculations were carried out varying the value of one parameter at a time and considering the effect on concrete and steel stresses. The influence of the modulus of elasticity used in calculations of thermal effects is discussed and illustrated. M. Diver and A.C. Paterson
Part l describes flexural tests on smallmasonry specimens and tests on full-sized walls, without preload, up to 5.5m long and 3.6m high, uniformly loaded laterally by means of air bags. Results for 6l different clay bricks and three mortars have enabled characteristic flexuralstrengths to be related to the water absorptions of the units. A few results for concrete block walls are also reported. H.W.H. West. H.R. Hodgkinson and B.A. Haseltine
The need for experimental work in connection with lateral loading has been explained in Part 1. There is no less a need for a suitable design method based on experiment and, where possible, experience, that can be used in the limit state revision of CP lll . Part II discusses the possible design approaches that could make use of the data now available. B.A. Haseltine, H.W.H. West and J.N. Tutt
Mr. T. N. W. Akroyd continues the discussion of the engineer's responsibilities in law and the significance of the Lord's decision in Anns' case in a lively and informative way. He writes : Why do engineers write passionately in emotive language about matters which need to be thought out carefully, logically and unemotionally? A rhetorical question, perhaps, resulting from the consumption of wine and Verulam in unequal quantities but due in particular to the letter from Mr. Tietz on the subject of Anns' case (August 1977). Verulam