Time filter

Source Type

Houston, TX, United States

Fowmes G.J.,Loughborough University | Zamara K.,FCC Environmental
10th International Conference on Geosynthetics, ICG 2014 | Year: 2014

With diminishing waste streams many sites now face closure before filling to intended profiles. As a result, slopes which were intended as temporary waste slopes now require permanent capping solutions to be installed. These slopes are often steep and challenging to cap. Various stability and integrity issues arise with solutions including the use of reinforcement within the capping layers. However, on long slopes the total forces are often large and anchorage on benches can be problematic. Tapering the cover soils can achieve a stable solution; however, large soil volumes may be required to achieve a satisfactory resistance to failure. This paper considers a case study of a 72m high temporary waste slope requiring a permanent capping solution. Interface shear strength is critical on such steep slopes and sampling, testing and interpretation requires careful consideration. A number of shear strength tests were carried out as part of the project and this paper shall consider the designer's concerns around the interpretation of these tests for use in stability analysis. As part of construction of the regulating soil, variable material was delivered to site, some with moisture content higher than specified, thus potentially reducing the strength and introducing a weak layer. This paper considers the challenges in stability risk assessment, data interpretation and future instrumentation requirements at the site. Source

Dixon N.,Loughborough University | Zamara K.,Loughborough University | Zamara K.,Golder Associates | Jones D.R.V.,Golder Associates | Fowmes G.,FCC Environmental
Geotechnical Engineering | Year: 2012

Despite the relative maturity of landfill design practice, world-wide there are still significant numbers of large scale failures of waste bodies, often incorporating the lining system. In addition, there is growing evidence that post waste placement deformations in the lining system are leading to loss of function (i.e. discontinuous drainage layers, loss on protection and leaking liners). Best practice has established that both stability and integrity of the lining system must be assessed during the design process, and specifically that interaction between the waste body and lining system should be considered both in the short-term (i.e. during construction) and long-term (i.e. following waste degradation). The paper introduces available analysis approaches, reviews knowledge of waste behaviour required for such analyses and provides guidance on the mechanisms to consider. The need for field monitoring to validate numerical models is established as is the need for extensive measurements of waste mechanics properties linked to a standard classification system to aid comparison and use. The benefits of using probability of failure analysis to incorporate material and test variability in design are highlighted. Source

Habib M.,University of Peshawar | Miles N.J.,The University of Nottingham Ningbo, China | Mohabuth N.B.,FCC Environmental | Hall P.,The University of Nottingham Ningbo, China | And 2 more authors.
Particulate Science and Technology | Year: 2014

Separation of particle mixtures in micron size range is of concern to many industrial processes. The experimental work presented in this article has looked into the operational assessment of a novel vertical vibration driven particle separator by using a positron emission particle tracking (PEPT) technique. In addition to PEPT, a smoke blanket visualization technique was used to track the intestinal air movements during the course of vibration induced particle separation. Three different finely sized glass and bronze particle mixtures that formed an average particle bed heights of 20, 40, 60, 80, and 100 mm in separation cells of thickness 20 and 40 mm were used to investigate the particle separation behavior. For a range of operating conditions, the results showed in favor of low particle bed heights (below 40 mm), lower vibration frequency (30 ± 10% Hz) and a small partition separation gap size of 5 mm for optimum separation of bronze particles in the presence of air. © 2014 Copyright Taylor and Francis Group, LLC. Source

FCC Environmental | Entity website

Over 50million people in more than 5,000 municipalities around the world benefit from the services we provide. We employ a variety of collection systems according to each citys needs, using a combination of vehicles and containers designed to maximize efficiency and minimize the environmental footprint in terms of noise and emissions ...

Discover hidden collaborations