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This paper discusses the rationale behind the redefinition of the design gust speed in the Australian/New Zealand Standard for Wind Actions, AS/NZS 1170.2, as one with a duration of 0.2 seconds, based on a moving average of that time. The origin of the basic gust in the Australian Standards since 1971, from the Dines anemometer, is discussed, and the relative response of that anemometer to gusts is compared with the current recording system based on cup anemometers, with digital processing including a moving average filter. The cup anemometers in the automatic weather stations (AWS), with the associated 3-second digital averaging, that have replaced the Dines in Australia, since the early 1990s, are shown to significantly attenuate the high frequency wind fluctuations, and hence record lower gust wind speeds. The correction factors provided in the paper for the post-1990 gusts should be applied by writers of future editions of the standard wishing to use AWS data. It should be noted that users of the standard will not be affected by the redefinition as there will be no changes to either the wind speeds or the shape factors. [ABSTRACT FROM AUTHOR]

This paper proposes the sampling factor for the mean test value as an alternative to that of the minimum test value of resistance for acceptance in prototype testing. The sampling factor was introduced in Australian/New Zealand loading standards AS/NZS 1170.0 to account for the uncertainties involved in prototype testing of a small number of samples to derive the characteristic properties of a much larger population. It requires the use of the minimum test value divided by a sampling factor to obtain an estimate of the 5-percentile value of the population. It is shown that while both procedures are mathematically equivalent, the use of mean value leads to more consistent estimate of the characteristic value of resistance. The sampling factors for the minimum and the mean test values are provided for Weibull and lognormal distributions by Monte Carlo simulation. This process was not feasible at the time when the original minimum value method was proposed about three decades ago. [ABSTRACT FROM AUTHOR]

A lot of clay has fl owed through the kilns since the 1989 Newcastle earthquake. Several signifi cant changes have occurred to make masonry veneer construction safer and stronger over this period, both in the methods of construction of the veneer and the understanding of the behaviour of the veneer panels. These changes have lead to the conclusion that masonry veneer construction can be reliably considered to provide some bracing resistance to a light timber-framed structure, even if only to resist its own inertial loads. Recent research undertaken at BRANZ has investigated the behaviour of full-scale brick veneer single- and two-storey buildings under slow static and dynamic cyclic loading. This paper describes the developments that have occurred since 1989 and this recent research that has provided the new confi dence in the seismic performance of clay brick veneer. [ABSTRACT FROM AUTHOR]

Cold-formed C-channel sections have been used in portal frame sheds for a wide range of domestic, agricultural and light industrial applications for many years in Australia and New Zealand. However, in many cases the knee joint designs have been copied from hot-rolled portal frame designs, regardless of the clearly different nature of the sections being connected. Testing has demonstrated that many of the joint designs widely used in practice do not achieve the moment capacity of the sections and fail prematurely. Various alternative joint designs have been proposed and constructed, but many of these also fail to meet required capacities under test. This paper reviews the issues relevant to design and construction of such knee joints and considers the positives and negatives of the principal categories of joints currently used in the cold-formed shed industry. It summarises the findings from a large number of tests conducted over a number of years on many of these joints. It concludes with some cautionary notes regarding what is required for design and construction if these commonly used structures are to function as intended from a structural viewpoint. [ABSTRACT FROM AUTHOR]

Brick veneer construction is a very common form for residential structures in Australia and is growing in popularity in New Zealand. The structural frame is made from steel or timber, and non-structural brick walls are attached to the frame via brick ties. Under earthquake loading there is a complex interaction between the frame and veneer walls, particularly in the outof- plane direction, where there is risk of brick wall collapse. While there is a standard component test method for assessing the seismic capacity of brick ties, this method has been developed around brick veneer on timber studs. In order to realistically assess the overall performance of brick veneer construction with steel framing, a full scale one-room test structure "Test House" was tested on a shaking table. The Test House incorporated veneer walls with different geometries. It was subjected to varying levels of the El-Centro earthquake ranging from moderate serviceability limit state ground motion to well beyond the design maximum considered earthquake for New Zealand. These levels of shaking were selected in order to ascertain the response for specifi c limit states to the New Zealand Loading Standard and to compare against minimum performance requirements. Comprehensive measurements on the frame and veneer walls were taken, including acceleration, drift and differential movements between the frame and veneer. The Test House performed very well, with no brick loss up to 2.6 times El-Centro earthquake, which is well in excess of all performance requirements. This paper presents a summary of the outcomes from the experimental test program. [ABSTRACT FROM AUTHOR]