Search

The earth is experiencing unprecedented change driven by increasing population, industrialisation and urbanisation. This is leading to rapid climate change and scarcity of resources. There is growing agreement globally of the need to deliver sustainable development to improve the lives of millions of people in low and middle income countries through provision of clean water, sanitation, energy and transport solutions. The response of the international community to this challenge is via the United Nations programme (published in January 2016), which establishes 17 Sustainable Development Goals (SDGs) including response to climate change. These SDGs will guide decisions taken by nations and organisations over the next 15 years. This paper is the written version of the opening keynote lecture delivered to the 3rd Pan American Conference on Geosynthetics in Miami Beach, USA, in April 2016; it considers the role that geosynthetics can make in achieving the SDGs. Scientific evidence for climate change is presented, and the value and uncertainty in available climate change information is discussed to inform its use in design. International agreements on reducing greenhouse gas emissions are based on country specific action plans for mitigation and adaptation against climate change, and the potential for geosynthetics to help achieve these targets is identified. Finally, approaches for calculating embodied carbon for solutions incorporating geosynthetics are introduced and case studies that provide evidence for the 'sustainability' case for geosynthetics are summarised. The geosynthetics community is challenged to play a leading role in helping to deliver the SDGs and hence a better future for populations worldwide. [ABSTRACT FROM AUTHOR]

This paper presents a numerical method for considering soil-atmosphere interaction applied to infiltration into an unsaturated geosynthetic reinforced soil wall and its effect on wall stability. A hypothetical nonwoven geotextile reinforced soil wall was subjected to simulated conditions of evaporation and precipitation over 2 years considering local climate variation in São Paulo city, Brazil. Net infiltration and actual evaporation were quantified inside and outside the reinforced zone, allowing for the assessment of changes in soil suction and factors of safety. The study discusses the implications of using in-plane draining reinforcements (e.g. nonwoven geotextiles) and soil-atmosphere effects. Results show that soil suction and factors of safety variation are more dependent on consecutive days of precipitation than on isolated heavy rainfalls. For the climate conditions considered in this study, results show that approximately 50% of the precipitation and potential evaporation transformed into net infiltration and actual evaporation, respectively. Additionally, the numerical results indicate that after the first wetting of the soil inside the reinforced soil zone, the evaporation to the atmosphere did not remove water from the inside of the geosynthetic reinforced wall because of the capillary break. [ABSTRACT FROM AUTHOR]