Effect of exposure conditions and concrete quality on pyrrhotite oxidation and internal sulfate attack

Thousands of homes in County Donegal, Ireland, are damaged by cracks formed a few years after construction. The authorities have erroneously attributed the damages to the presence of muscovite mica in the concrete blocks used to build the homes. Only recently, research has shown that pyrrhotite oxidation triggering internal sulfate attack (ISA) is the cause. In this study, the strip foundation, the rising blocks elevating the structure to ground level and the inner and outer leaf of one affected home are investigated. As these four types of structural components differ by concrete quality, exposure condition or both, their effect on pyrrhotite oxidation and ISA is investigated. Sulfur analysis, X-ray diffraction and scanning electron microscopy are used to characterize the concrete

Concrete Productivity And Performance Comparison Of Pumped Concrete For High Rise Structure

This study involves, case study of various sites regarding the productivity of concrete. This study involves collection of data information speed on concrete placing, time of concreting, volume, rate of concreting and relation between them with respect to height and type of structural member is analysed. The quantitative analysis of the collected data’s has been discussed by means of graphs and empirical formula. A relation between height of the building and speed of concrete placing is derived using the observations

Family Group Conference Experiences From The Perspective Of Volunteer Facilitators

This study examined the experiences of volunteer Family Group Conference (FGC) facilitators for the purpose of understanding how they experience and manage their role in the FGC process. By focusing on the benefits and challenges of volunteer FGC facilitators, this research adds a new perspective to the limited literature on FGC facilitators. Semi-structured, face-to-face interviews were conducted with 11 volunteer Family Group Conference facilitators in order to create a deeper understanding of these volunteers\u27 experiences. The Ecosystems Perspective and Uncertainty Reduction Theory created a framework for understanding the complex role of the FGC facilitator and allowed for a more detailed examination of their experiences. The findings from the research illustrate the rewarding, challenging, and emotionally-charged work of a volunteer Family Group Conference facilitator as well as the role communication plays in managing these experiences. Results also indicate that volunteer facilitators believe their presence as volunteers is comforting for participants in the FGC program and has a positive impact on the outcome of the conference. This research contributes to existing FGC and volunteer literature, and has implications for practice in the utilization of volunteers, as well as exposing issues that can be addressed to strengthen the process