Mr. R. A. D. Noble: ‘In their paper Bobrowski and Bardhan-Roy put forward a simple empirical method for calculating the ultimate strength of reinforced and prestressed concrete beams in combined flexure and shear which applies equally to rectangular and I sections. The treatment of the test results in this paper leads me to the conclusion that the actual thickness of the web in prestressed I beams does not play such a significant part in determining the actual ultimate strength in combined flexure and shear as it would appear to do either in existing design practice based on principal tensile stresses, or in new proposals for the Unified Concrete Code. It is of particular interest that some of the data is taken from tests at elevated temperatures under exposure to fire, since recent proposals by the FIP, which are likely to be adopted in this country, recommend limitations to the thickness and slenderness of webs in this context. In view of the material presented in this paper it seems to me that these proposals might be unnecessarily restrictive.