Webinar Summary: 

The stability of both the base and cap liner systems are critical to the long term performance of any landfill. Slip failure of these systems is often catastrophic in terms of the operation of the landfill and in some ways more damaging the design engineers reputation than other failures due the visual impact these failures have on public perception of landfills in general. Landfill stability failures have been occurring since the first engineered liner designs were introduced in the 1970’s and continue to this day and the main tool used by design engineers to predict and prevent this from occurring is the use of laboratory based interface friction testing according to ASTM D5321 & ASTM D 6243. As with many standardized test methods while the standard is designed to promote uniformity and repeatability of test, due to the number of different materials and configurations laboratories can often interpret the standard differently and this will have an impact on the outcome of the test. As a result, it is critically important that design engineers requiring the testing specify exactly how the specimens are prepared and have at least a basic understanding of how to read a shear report to ensure the results obtained are reasonable.

This presentation will cover some failures which prompted the need for interface friction and the key factors to consider when specifying and reviewing interface friction testing.

Warren Hornsey

Director – TRI Australasia

Warren is Professional Civil Engineer and has worked in the civil engineering field in Africa, Europe and Australia. He has been active in the geosynthetic field since 1997 with experience in geosynthetic testing, research & development and design of structures involving geosynthetics.  His experience covers a diverse range of geosynthetic applications from landfill lining to reinforcing and coastal protection. He has published over 20 peer reviewed technical papers relating to geosynthetic design and application.