Bio-engineering Mitigation Debris of Flow

生物工程减缓泥石流

• 批准号: 1846851
• 金额: --
• 依托单位: University of Dundee
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-1846851
• 关键词: Bio; engineering; Mitigation; Debris; Flow

Under the impact of climate change, rainfall-induced debris flow events have been increasingly reported and these have led to significant socio-economic losses. Existing mitigation methods include concrete baffles, but these methods have high embodied CO2 that would further promote climate change. Slope bioengineering such as brush layering [1] is an alternative, "green" and low-carbon technique (Fig. 1). Plant shoot might be used to attenuate the debris impact energy, and subsequently the root pull-out resistance may be mobilised to resist against the drag force induced on the plant. There is, however, no study evaluating such soil-plant-debris interaction and its effect on debris flow mobility. The aim of this PhD project is to investigate the effectiveness of using brush layering to reduce the mobility of a debris flow mass. The objectives of this project are to(i) Determine the drag force exerted on plant shoot during the transport of a debris mass;(ii) Quantify the soil-root mechanical pull-out resistance against the drag force;(iii) Quantify the reduced mobility of a flow mass due to bioengineering mitigation; and(iv) Evaluate the performance of brush layering technique against rigid baffles method;A new large-scale experimental flume will be developed for modelling different debris flow events. Brush layering will be modelled by 3-D printing some representative plant traits [2], hence (i) removing the need to wait for the plant growth and (ii) enabling repeatable results. Debris flow event with a known volume of dry granular soil will be triggered at the upstream of the flume. Any changes of the flow characteristics of a debris mass across the brush layering will be monitored and compared with cases without bioengineering mitigation, and cases that mitigated by rigid baffles. Any favourable plant traits and plant arrangement that could enhance the performance of the bioengineering technique will be identified.References:Stokes, A., et al. 2015. Ecological mitigation of hillslope instability: ten key issues facing researchers and practitioners. Plant and Soil, 377: 1 - 23.Liang, T., et al. 2014. Modelling the seismic performance of rooted slope from individual root-soil interaction to global slope behaviour, Geotechnique, 65(12): 995 - 1009.

受气候变化影响，降雨引发的泥石流事件日益增多，造成了重大社会经济损失。现有的缓解方法包括混凝土挡板，但这些方法含有大量二氧化碳，会进一步促进气候变化。刷层等边坡生物工程[1]是一种替代性的“绿色”低碳技术（图1）。植物芽可用于减弱碎片冲击能量，随后可利用根拔出阻力来抵抗对植物产生的阻力。然而，还没有研究评估这种土壤-植物-泥石流相互作用及其对泥石流流动性的影响。该博士项目的目的是研究使用刷层分层来降低泥石流团块流动性的有效性。该项目的目标是（i）确定碎片团运输过程中施加在植物芽上的阻力；（ii）量化土壤根部对阻力的机械拉拔阻力；（iii）量化减少的阻力由于生物工程缓解而导致的流动质量的流动性； (iv) 相对于刚性挡板方法评估刷子分层技术的性能；将开发一种新的大型实验水槽来模拟不同的泥石流事件。刷子分层将通过 3D 打印一些代表性植物性状进行建模 [2]，因此 (i) 无需等待植物生长，并且 (ii) 能够获得可重复的结果。已知体积的干燥颗粒土壤的泥石流事件将在水槽的上游触发。将监测穿过刷层的碎片质量的流动特性的任何变化，并与没有生物工程缓解的情况以及通过刚性挡板缓解的情况进行比较。任何可以增强生物工程技术性能的有利植物性状和植物排列都将被识别。参考文献：Stokes, A., et al. 2015.山坡不稳定的生态缓解：研究人员和实践者面临的十大关键问题。植物与土壤，377：1 - 23。Liang，T.，等。 2014. 从单个根-土相互作用到整体坡行为对有根边坡的地震性能进行建模，岩土工程，65(12)：995 - 1009。