Influence of Salt-Lime Stabilization on Soil Strength for Construction on Soft Clay

Construction on soft soil is one of the most challenging situations faced by geotechnical engineers. The heterogeneous and complex nature of soil, especially those containing organic clay, often makes it impossible for the construction specification to be addressed properly. Generally, clay exhibits low strength, high compressibility, and strength reduction when subjected to mechanical disturbance. This means that construction on clay soil is vulnerable to bearing capacity failure induced by low inherent shear strength. All these properties can be improved by the effective stabilization of soil. This study analyzed the effectiveness of incorporating salt-lime mixtures at various dosages in improving the strength increment of the soil. The results indicate that among different combinations of salt and lime, the best performance in terms of strength increase was achieved by adding 10% NaCl with 3% lime in the soil. The outcome of this study focuses on enhancing the ultimate strength of soil and its implementation in the field of foundation engineering.

Assessment of Community Based Climate Change Risk Focusing Agriculture and Fisheries Sector in Haor Areas of Bangladesh

The research paper aims at understanding the level of climate change risk of the Haor areas of Bangladesh. It follows a participatory approach, using Focus Group Discussion (FGD) and Key Informant Interview (KII) to identify important climate change induced hazards, assess the probability of occurrences of the hazards and level of their consequences. Using geo-spatial techniques, the paper prepares hazard risk maps and risk hotspot maps. Policy documents, previous researches, and Government statistics and reports helped to develop the concepts and planning of the research. The unparalleled hydro-ecological attributes of Haor areas pose both opportunities and constraints for the local population. Poverty, lack of basic infrastructure and amenities, awareness and external support have already put the people in Haor areas in a vulnerable situation while the recurring natural hazards and shifting pattern of climate are making the constraints nearly unmanageable. Excessive rainfall in the monsoon and drought in the dry season is affecting the farming and fishery-based communities the most. The community perceptions on hazards, their occurrences, consequences and relative importance of each hazard for the agriculture or fisheries sector in the study area have been collected from the FGDs and subsequently analyzed to produce individual and multi-hazard risk maps for the area based on scoring. This information is also used to rank the Upazillas in the study area depending on risk level. The community people were also asked to select the important elements or structural facilities at risk in their area needed for their life and livelihood. Based on this selection, risk hotspot map for the study area has been prepared using GIS based weighted overlay methods. The final risk hotspot map identifies about hundred unions in the area as hotspots. This paper might encourage the local government organizations to make choice on the intervention as well as intervention needs for protecting livelihoods in the study area. The results of the study will be helpful in planning adaptation options for future for the study area as well as effectively allocate resources/investments to protect population and livelihoods from possible climate change induced hazards.