An integrated approach for evaluating the effectiveness of landslide risk reduction in unplanned communities in the Caribbean

Despite the recognition of the need for mitigation approaches to landslide risk in developing countries, the delivery of ‘on-the-ground’ measures is rarely undertaken. With respect to other ‘natural’ hazards it is widely reported that mitigation can pay. However, the lack of such an evidence-base in relation to landslides in developing countries hinders advocacy amongst decision makers for expenditure on ex-ante measures. This research addresses these limitations directly by developing and applying an integrated risk assessment and cost-benefit analysis of physical landslide mitigation measures implemented in an unplanned community in the Eastern Caribbean. In order to quantify the level of landslide risk reduction achieved, landslide hazard and vulnerability were modelled (before and after the intervention) and project costs, direct and indirect benefits were monetised. It is shown that the probability of landslide occurrence has been substantially reduced by implementing surface-water drainage measures, and that the benefits of the project outweigh the costs by a ratio of 2.7 to 1. This paper adds to the evidence base that ‘mitigation pays’ with respect to landslide risk in the most vulnerable communities – thus strengthening the argument for ex-ante measures. This integrated project evaluation methodology should be suitable for adoption as part of the community-based landslide mitigation project cycle, and it is hoped that this resource, and the results of this study, will stimulate further such programmes.Landslide modelling, Risk assessment, Cost Benefit Analysis, Developing countries, Community

PROPERTIES OF NON-CONVENTIONAL WASTE AND GEOMATERIALS FOR REUSE IN EXCAVATION SITES

Reuse and recycling of waste material from excavation and mining/quarrying activities is a global issue that received significant attention in the last decades. The links among local geology, excavation methods, spoil treatment and strategies for recycle have been identified as unavoidable in terms of early physical, chemical and mechanical characterisation of spoils. The emergence of a range of industrial waste streams and the environmental, economic and technical considerations arising from their recycle and reuse still need a comprehensive technical and validated procedure for acceptance. This paper describes the screening tests and treatment options for material recycling in the framework of an original spoil classification system, also for specific applications, such as drainage layers, covering of dumps, rehabilitation of abandoned sites. The experience learnt by the Authors from the development of suitable methodologies for characterisation and management of spoil waste can be extended to other waste such as glass waste, gypsum, rockwool, glasswool, granulates, chipping particles, polymeric cuttings which show similarities with soils and geomaterials in terms of ‘bulk behaviour

A Platform for Proactive, Risk-Based Slope Asset Management, Phase II

INE/AUTC 15.0

A multi-objective decision making model for risk-based maintenance scheduling of railway earthworks

Aged earthworks constitute a major proportion of European rail infrastructures, the re-placement and remediation of which poses a serious problem. Considering the scale of the networks involved, it is infeasible both in terms of track downtime and money to replace all of these assets. It is, therefore, imperative to develop a rational means of managing slope infrastructure to determine the best use of available resources and plan maintenance in order of criticality. To do so, it is necessary to not just consider the structural performance of the asset but also to consider the safety and security of its users, the socioeconomic impact of remediation/failure and the relative importance of the asset to the network. This paper addresses this by looking at maintenance planning on a network level using multi‐attribute utility theory (MAUT). MAUT is a methodology that allows one to balance the priorities of different objectives in a harmonious fashion allowing for a holistic means of ranking assets and, subsequently, a rational means of investing in maintenance. In this situation, three different attributes are considered when examining the utility of different maintenance options, namely availability (the user cost), economy (the financial implications) and structural reliability (the structural performance and subsequent safety of the structure). The main impact of this paper is to showcase that network maintenance planning can be carried out proactively in a manner that is balanced against the needs of the organization.Geo-engineerin

Laboratory test for EPB tunnelling assessment:results of test campaign on two different granular soils

Earth Pressure Balanced shields are currently the most utilized tunnelling machines throughout around the world. The possibility of using conditioning agents that change the mechanical and hydraulic behaviour of a soil, changing it into a plastic paste and thus permitting soil pressure applications at the tunnel face, is the key point to explain the increasing utilization of this technology. Despite its great importance, not much laboratory researches can be registered on soil conditioning, particularly for cohesionless soils. The conditioning criterion is usually defined on the basis of a trial-and-error procedure developed directly at the job sites. A test that is able to simulate the extraction of soil from the bulk chamber with the screw conveyor inclined upwards, as in real machines, can offer a quantitative indication of the conditioned soil behavior for EPB use. The characteristics of the device and the results obtained on many different types of soil are discussed in order to point out the great importance and quality of results that can be achieved using the proposed test devic