地形発達効果および気候変動を考慮した斜面危険度の広域評価

考虑地形发展效应和气候变化的边坡风险大区域评估

• 批准号: 16F16378
• 负责人: 中北 英一
• 金额: $ 1.41万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for JSPS Fellows
• 财政年份: 2016
• 资助国家: 日本
• 起止时间: 2016-11-07 至 2019-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16F16378/
• 关键词: vegetation; groundwater; Poroelasticity; Mohr-Coulomb theory; Finite element analysis; hillslope stability; extreme climate; Numerical simulation; landscape evolution; climate change

As our environment becomes warmer, extreme climate becomes more frequent. Global warming directly or indirectly influences hillslope vegetation, landform and stability, which are the dominant factors for hazard occurrence on slopeland. To perform slopeland hazard assessment, the analysis target is landslide which is the origin of all kinds of slopeland hazards. This research aims to develop a methodology which can achieve high resolution prediction of slopeland hazards under climate change impact. In last two years, we have successfully finished the development of a novel mechanically based landslide model to identify three-dimensional unstable zones prone to landslide in irregular topsoil layers on steep and vegetated hillslopes by using Poroelasticity, Mohr-Coulomb failure theory and tree allometry. Two historical events occurred in Hiroshima, Japan in July 2014 and in Seoul, Korea in July 2011 are used for verification and case studies. The simulated results are in good agreements with real field conditions. For 3D groundwater modeling, we successfully analytically investigate hydraulic groundwater theory to propose a new way for correct modeling, and perform numerical modeling of groundwater table evolution in irregular 3D soil layer using relaxation approach. Both of the models above have been integrated to achieve 3D landslide prediction in the high resolution. However, the part for landscape evolution simulation is still under development, and to be appear in the near future for comprehensive modeling of hillslope process under long-term climate change influence.

随着我们的环境变得越来越温暖，极端气候变得更加频繁。全球气候变暖直接或间接地影响着坡面植被、地形地貌和稳定性，而这些是坡面灾害发生的主导因素。滑坡是各种边坡灾害的成因，进行边坡灾害评价，其分析对象是滑坡。本研究旨在发展一种方法，可以实现高分辨率的预测气候变化影响下的斜坡灾害。在过去两年，我们成功地完成了一个新的基于力学的滑坡模型的发展，以确定三维不稳定区容易发生滑坡的不规则表土层陡峭和植被山坡上使用孔隙弹性，摩尔-库仑破坏理论和树异速生长。2014年7月发生在日本广岛和2011年7月发生在韩国首尔的两个历史事件被用于验证和案例研究。模拟结果与真实的现场情况吻合较好。对于三维地下水建模，我们成功地对地下水水力学理论进行了解析研究，提出了正确建模的新方法，并采用松弛法对不规则三维土层中的地下水位演化进行了数值模拟。将两种模型进行集成，实现了高分辨率的三维滑坡预测。然而，景观演化模拟部分仍在发展中，并将在不久的将来出现，长期气候变化影响下的山坡过程的综合模拟。

项目成果

A New Model of Subsurface Flow in an Unconfined Surface Soil Layer on an Irregular Hillslope

不规则山坡无侧限表层土层地下流的新模型

• 发表时间: 2018
• 作者: Wu;Y.-H.;Nakakita;E.
• 通讯作者: E.

A new method of fully three dimensional analysis of stress field in the soil layer of a soil-mantled hillslope

土覆山坡土层应力场全三维分析新方法

• 发表时间: 2017
• 作者: Ying-Hsin Wu;Eiichi Nakakita
• 通讯作者: Eiichi Nakakita

Gangneung-Wonju National University(韓国)

江陵原州国立大学（韩国）

A Transient Model for Shallow Groundwater Table Evolution in An Unconfined Sloping Aquifer Considering Variable Rainfall Recharge

考虑可变降雨补给的无承压倾斜含水层浅层地下水位演化瞬态模型

• 发表时间: 2018
• 期刊: DPRI Annuals
• 作者: Wu;Y.-H.;Nakakita;E.
• 通讯作者: E.

A New Method for Safety Analysis of Vegetated Hillslopes under Different Rainfall

不同降雨量下植被山坡安全分析的新方法

• 发表时间: 2017
• 作者: Ying-Hsin Wu;Eiichi Nakakita
• 通讯作者: Eiichi Nakakita