Numerical Analysis of Concrete Block Pavements and Comparison of Its Settlement with Asphalt Concrete Pavements Using Finite Element Method

Regarding time consuming properties and complex intervention of layers and different materials, it is better to replace laboratory based design and analysis of pavements with quick and powerful software including finite element, finite reduction software and etc. Using finite element software ABAQUS, at first, the paper investigated effects of changes of concrete block thickness in vertical stress and it was validated with experimental results. Also, using this software, effect of asphalt concrete thickness change was studied in vertical strain. And finally, results of finite element model were validated, using experimental data. Regarding that finite element analysis is suitable for crust environments and concrete block pavement does not have such environment, this research tends to compare these two types of pavements, using mathematical equations to analyze settlement. To do this, first, two models were designed, one for concrete block pavement and the other one for asphalt concrete pavement. Subgrade and base layers' models were the same in geometrical point of view and types of materials, but thickness of asphalt and concrete block pavement layers and bedding sand changed, alternatively and based on the obtained relations and diagrams, there has been a chance to equate indices of these two types of pavements

Drivers of GHG emissions from dietary transition patterns in China: Supply versus demand options

Diets have been changing drastically in China in the recent decades and this change has contributed considerably to greenhouse gas (GHG) emissions. In determining effective mitigation strategies for future emissions, it is necessary to know how emissions related to diet vary over time in overall magnitude and due to compositional changes driven by socioeconomic dynamics. This study evaluates the change in dietary GHG emissions in China during the 1997–2011 period by linking environmentally extended input–output tables with individual daily food intake data. It further decomposes the contribution to GHG emission changes of various socioeconomic driving factors. The results show that GHG emissions related to national diet have been decreasing from 1,180 Mt CO2e to 640 Mt CO2e (a 54% decline), largely due to technical innovation that has reduced the emissions per calorie of food (135% of the total reduction). The change in dietary patterns has had mixed effects, with a decline in calorie intake reducing emissions by 21% while increases in animal‐sourced food consumption have raised emissions by 25%. Our findings stress the importance of technical progress in the historical change in dietary GHG emissions and suggest a focus on behavior changes for future research and policymaking, which has the potential to promote dietary changes toward less animal product consumption. Our findings highlight the importance of both technological and demand‐side behavioral options in reducing the impact of diets on GHG emissions

Spatial, temporal, and demographic patterns in prevalence of smoking tobacco use and attributable disease burden in 204 countries and territories, 1990–2019: a systematic analysis from the Global Burden of Disease Study 2019

10.1016/s0140-6736(21)01169-7The Lancet397102922337-236