Norms and Practices in UN Peacekeeping: Evolution and Contestation

This is an introduction to a special section of International Peacekeeping

UN Peacekeeping at 75: Achievements, Challenges, and Prospects

This year marks the 75th anniversary of what the UN itself understands to be its first peacekeeping operation. It is therefore an appropriate time to reflect on the track record of UN peacekeeping in its efforts to try to maintain and realize peace and security. Moreover, this milestone invites us to ponder what lies ahead in the realm of peacekeeping. For this reason, this forum article brings together both academics and UN officials to assess the achievements and challenges of UN peacekeeping over the past 75 years. Through a dialogue among peacekeeping scholars and practitioners, we hope to identify current trends and developments in UN peacekeeping, as well as explore priorities for the future to improve the effectiveness of peacekeeping operations in terms of achieving their mandate objectives, such as maintaining peace, protecting civilians, promoting human rights, and facilitating reconciliation. This forum article is structured into six thematic sections, each shedding light on various aspects of UN peacekeeping: (1) foundational principles of UN peacekeeping - namely, consent, impartiality, and the (non-)use of force; (2) protection of civilians; (3) the primacy of politics; (4) early warning; (5) cooperation with regional organizations; and (6) the changing geopolitical landscape in which UN peacekeeping operates

Geotechnical properties of Dublin boulder clay

Geotechnical characteristics of Dublin Boulder Clay (DBC) based on detailed site investigation and site experience from some recent large projects in Dublin are presented. This paper attempts to synthesise available information in parallel with recent work by Skipper et al (2005), who provide an updated understanding of the geology of the DBC. Having assessed the effects of sampling disturbance, the paper characterises the various formations and sub-units of the DBC. The interpreted material behaviour is related to observed engineering performance. It was found from the behaviour of earth retained structures that intact, clayey, DBC formations are 2 to 3 times stiffer than assessed from high quality laboratory tests on block samples. DBC is shown to be significantly stiffer than other well-characterised tills. Relatively inexpensive Multi Channel Surface Wave techniques (MASW) can give very reliable estimates of in situ small strain stiffness. High undrained triaxial compression strengths were measured and it appears that simple UU tests on high quality specimens give good results. Significant strength anisotropy was suggested by undrained triaxial extension strengths that were only 30% to 50% of the triaxial compression strengths. Field horizontal permeability values of the intact clayey till units have a representative mean of about 10-9 m/s and when compared to laboratory values suggest that the material may exhibit some degree of anisotropy of permeability. Overall, the measured engineering parameters for the DBC are favourable for many construction projects. Further work is required in order to understand the in situ horizontal stress profile and the stiffness anisotropy of the till. KEYWORDS: Glacial soils, In situ testing, laboratory tests, site investigation, strength, stiffness.Not applicabl