THE ABRASION TESTING OF CONCRETE PAVERS

SUMMARY This paper describes an in-depth evaluation of an abrasion testing procedure for concrete pavers developed in Australia The test involves abrasion of the paver surface by a rapidly rotating ball race under load. Water is used both to lubricate the race and to remove debris. The investigation included the study of factors affecting the test results such as the load applied to the ball-race, the speed inclination and numbers of revolutions of the race, the speed inclination and numbers of revolutions of the race, the water flow and the hardness and wear of the ball bearings. Additional tests were conducted to establish the intrinsic variability of the test procedure. Based on the test results both the advantages and limitations of the test as a means for characterising the abrasion resistance of pavers are outlined and discussed

The Electronic journal and its implications for the digital library

This item is not the definitive copy. Please use the following citation when referencing this material: McKnight, C., Dillon, A. and Shackel, B. (1996) The electronic journal and its implications for the digital library. In T. Harrison and T. Stephens (eds.) Computer Networking and Scholarly Communication in the 21st Century. NY: SUNY Press, 351-368. 1. INTRODUCTION: It is now over ten years since the first electronic journal experiments (e.g., EIES, BLEND) and the intervening years have not seen researchers being idle in this field. Indeed, while experiments have continued apace in an attempt to answer various questions such as the appropriateness of particular interfaces, electronic journals have continued to appear. The third edition of the ARL list (Okerson, 1993) contains 45 electronic journals while the first edition, only two years earlier (Okerson, 1991), listed only 27. This might suggest reasonably rapid growth but in actual fact represents a high rate of turnover also -- 16 of the original 27 do not appear in the latest list. We therefore start this chapter from the assumption that electronic journals will continue to be a feature of the scholarly communication process, although not all will survive. Our second assumption arises from our experiences in the design, implementation and evaluation of information technology based systems in general, not just electronic journals. That is, we assume that in order to be acceptable, any system attempting to replace an existing technology must enable users to perform their necessary tasks in a way which is at least as easy as the existing system. The new system must offer at least as much (and preferably more) than the existing system, otherwise motivation to move from the old to the new is not high. In the present context, this means that the successful electronic journals will be those which not only support the scholarly communication process and all the other user requirements satisfied by paper based journals, but also support additional, enhanced facilities such as tailorable presentation formats, integrated interactive discussion about articles, flexible indexing and retrieval, hypertext linking and so forth

Experience in the application of permeable interlocking concrete paving in Australia

This paper reports assessments of a range of permeable interlocking concrete pavements (PICP) that have been in service around Australia for periods of around 10 years. Each of the assessments is supported by a critical review of the properties and in-service performance of the pavements based on in-situ measurements and inspections, supplemented by laboratory test data. Factors studied in-clude the infiltration rate, structural properties and performance together with lifespan and physical filtration efficiency. The effects of sediment load and pavement clogging have also been examined. Most of the pavements studied had not been subject to routine or systematic maintenance. Despite this, the study showed that, up to 10 years of service, most pavements were still capable of good in-filtration. Sweeping the pavement surface was shown to be beneficial to infiltration and laboratory tests confirmed that most fine sediment was trapped in the upper portions of the jointing materials. Overall, the results tend to indicate that, at least under Australian conditions, the need to routinely sweep permeable paving may not be as necessary as is often assumed in the Northern Hemisphere.