Analysis of debris flow control effect and hazard assessment in Xinqiao Gully,Wenchuan M_(s)8.0 earthquake area based on numerical simulation

Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the effectiveness of the debris flow control project and evaluated the debris flow hazards.Through field investigation and numerical simulation methods,the indicators of flow intensity reduction rate and storage capacity fullness were proposed to quantify the effectiveness of the engineering measures in the debris flow event.The simulation results show that the debris flow control project reduced the flow intensity by41.05%to 64.61%.The storage capacity of the dam decreases gradually from upstream to the mouth of the gully,thus effectively intercepting and controlling the debris flow.By evaluating the debris flow of different recurrence intervals,further measures are recommended for managing debris flow events.

Deformation,structure and potential hazard of a landslide based on InSAR in Banbar county,Xizang(Tibet)

The Tibetan Plateau is characterized by complex geological conditions and a relatively fragile ecological environment.In recent years,there has been continuous development and increased human activity in the Tibetan Plateau region,leading to a rising risk of landslides.The landslide in Banbar County,Xizang(Tibet),have been perturbed by ongoing disturbances from human engineering activities,making it susceptible to instability and displaying distinct features.In this study,small baseline subset synthetic aperture radar interferometry(SBAS-InSAR)technology is used to obtain the Line of Sight(LOS)deformation velocity field in the study area,and then the slope-orientation deformation field of the landslide is obtained according to the spatial geometric relationship between the satellite’s LOS direction and the landslide.Subsequently,the landslide thickness is inverted by applying the mass conservation criterion.The results show that the movement area of the landslide is about 6.57×10^(4)m^(2),and the landslide volume is about 1.45×10^(6)m^(3).The maximum estimated thickness and average thickness of the landslide are 39 m and 22 m,respectively.The thickness estimation results align with the findings from on-site investigation,indicating the applicability of this method to large-scale earth slides.The deformation rate of the landslide exhibits a notable correlation with temperature variations,with rainfall playing a supportive role in the deformation process and displaying a certain lag.Human activities exert the most substantial influence on the spatial heterogeneity of landslide deformation,leading to the direct impact of several prominent deformation areas due to human interventions.Simultaneously,utilizing the long short-term memory(LSTM)model to predict landslide displacement,and the forecast results demonstrate the effectiveness of the LSTM model in predicting landslides that are in a continuous development and movement phase.The landslide is still active,and based on the spatial heterogeneity of landslide deformation,new recommendations have been proposed for the future management of the landslide in order to mitigate potential hazards associated with landslide instability.

Unraveling the hydraulic properties of loess for landslide prediction:A study on variations in loess landslides in Lanzhou,Dingxi,and Tianshui,China

Loess has distinctive characteristics,leading to frequent landslide disasters and posing serious threats to the lives and properties of local re sidents.The involvement of water repre sents a critical factor in inducing loess landslides.This study focuses on three neighboring cities sequentially situated on the Loess Plateau along the direction of aeolian deposition of loess,namely Lanzhou,Dingxi,and Tianshui,which are densely populated and prone to landslide disasters.The variations in hydraulic properties,including water retention capacity and permeability,are investigated through Soil Water Characteristic Curve(SWCC)test and hydraulic conductivity test.The experimental findings revealed that Tianshui loess exhibited the highest water retention capacity,followed by Dingxi loess,while Lanzhou loess demonstrated the lowest water retention capacity.Contrastingly,the results for the saturated permeability coefficient were found to be the opposite:Tianshui loess showed the lowest permeability,whereas Lanzhou loess displayed the highest permeability.These results are supported and analyzed by scanning electron microscopy(SEM)observation.In addition,the water retention capacity is mathematically expressed using the van Genuchten model and extended to predict unsaturated hydraulic properties of loess.The experimental results exhibit a strong accordance with one another and align with the regional distribution patterns of disasters.

The Occurrence Mechanism of Geological Disasters and Countermeasures in a Certain Area

In recent years, natural disasters in China have occurred frequently, especially large disasters such as earthquakes, floods and droughts, which have posed a serious threat to local public safety. In addition, the geological environment of local mountainous areas in China is complex and diverse, and climate change is large. Considering the dynamic coupling effect of rainfall conditions to stimulate geological disasters, this paper takes dynamic risk assessment technology as the guide, constructs a dynamic risk early warning model of geological disasters, establishes a prototype system, realizes dynamic risk assessment and emergency early warning of geological disasters at the regional level, and provides feasible technical support for targeted emergency disaster prevention. At the same time, the investigation and evaluation, mechanism research and monitoring and early warning related to the comprehensive prevention and control of geological disasters are important tasks that cannot be ignored, an important link in the emergency response system for geological disasters, and a key stage process to guide scientific disaster prevention. On the basis of exploring the mechanism and catastrophic effect of rainfall to stimulate landslides and mudslides, we will carry out in-depth research on disaster prevention countermeasures such as systematic engineering disposal, monitoring and early warning.

GEOLOGICAL HAZARDS AND THEIRS CONTROL

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Development laws of geological hazards along urban highway in Southwest China and countermeasures for prevention and control

China is a mountainous country with highly developed road geologic hazards, which pose a great threat to theconstruction and operation of highways, bridges, and tunnels and to the safety of people and property. This paperdiscussed the types, basic features, formation, and prevention conditions of road geologic hazards in China basedon field research and study data collected thus far. The study considered an urban area of a city in southwestChina as the center and a geological field investigation was performed over a total of 282 km on three importantlifeline projects. The results show: Types of geologic hazards along the highways are mainly avalanches, debrisflows, and landslides, respectively. Among them, the landslips are mainly distributed along the roads, with slip,dumping, and wrong break types as the main ones;the debris flows are widely distributed, mainly concentrated inthe river valleys;and the unstable slopes are relatively few in number. Geological disasters are characterized bylarge-scale and concentrated triggering in time and space, and a single disaster can easily trigger other disasters,thus forming a chain of disasters. Neotectonic movement, seismic activity, topography, climatic conditions,stratigraphic lithology, and human activities are important factors leading to geologic hazards in the study area.This study is of great practical significance for reducing the occurrence of roadbed diseases and prolonging theservice life of highways.

安徽省阜南县地质灾害风险调查评价研究

为深入探究并科学评价安徽省阜南县地质灾害高风险区域,确保当地居民生命财产安全,本文通过1∶5万比例尺地质灾害风险调查工作,对该县潜在的地质灾害类型、形成机制以及对人类社会构成的威胁进行了系统分析。基于调查数据和科学的风险评估方法,本文不仅提出了针对性的地质灾害风险管控策略,还全面总结了阜南县地质灾害的发育分布规律。这一研究不仅为阜南县地质灾害的防控提供了科学依据,也为类似地区的地质灾害风险管理提供了参考。

山区切坡活动引发地质灾害风险评估及其防控措施

以秦岭北麓西安市临潼区仁宗街道为研究区,在野外调查、遥感解译的基础上,确定、分析了40处地质灾害隐患点的发育特征及其主要影响因素;基于DEM数据,构建了研究区663个斜坡单元地质灾害风险评估体系,通过地质灾害易发性、危险性和易损性分析,得到了考虑斜坡稳定性和承灾体危害性的仁宗街道斜坡单元地质灾害综合风险评估结果;通过野外实地验证,证实了评估结果的准确性和可靠性。据此划分了地质灾害防治区,从防灾减灾和工程建设两维度提出了仁宗街道的地质灾害风险防控措施建议,为研究区国土空间规划提供参考依据。

青海隆务东山沟域潜在灾害链成链分析及防治对策

隆务东山位于青海省同仁县隆务河东侧,属于侵蚀剥蚀低山丘陵区,水土流失严重,沟域内山高坡陡,岩土结构松散,易于形成滑塌、泥石流等地质灾害,在形成和演化过程中呈现出明显的潜在灾害链效应,若再遭受持续降雨或暴雨,易发生大规模的链式灾害,对区域生态环境及下游居民安全造成严重威胁。通过详细的野外调查、遥感影像解译、气象水文数据分析,查明了隆务东山地质灾害发育分布特征,研究了潜在灾害链效应及防治对策。结果表明:隆务东山沟域潜在地质灾害链为典型的降雨诱发型地质灾害链,可归纳为降雨条件下沟源滑坡-泥石流、径流侵蚀-泥石流-沟道侧蚀-岸坡崩滑-堵溃型泥石流两类主要的潜在链式灾害结构;从成因角度重点分析预测了链生灾害之间可能存在的相互激发、转化关系,揭示了潜在灾害链成链过程及条件,并将第一条链划分为孕育启动、演化暴发及规模扩大三个阶段;第二条链划分为物源启动、水力侵蚀、沟道堵溃和灾害放大4个阶段;针对其潜在灾害链的演化机制及发展趋势,提出了监测追踪、水土分治、拦停成坪和固表生植的综合防治方案,旨在达到防灾减灾,保护生态环境的目的。

涪江源区韩家沟泥石流防治工程改进前后危险性分析

为了降低涪江源区左岸韩家沟泥石流的危害,文章采用遥感解译、野外调查、FLO-2D数值模拟等手段,查清了韩家沟泥石流特征及其防治现状,认为现有防治工程不能满足防灾需求,并据此提出改进的防治工程,对不同降雨频率下防治工程改进前后的泥石流危险性进行了研究,并分析改进防治工程的有效性。结果表明:韩家沟位于“8·8”九寨沟地震扰动区,震后泥石流物源丰富,导致每逢强降雨时泥石流频发。在10年一遇降雨频率下,丰河村及平松路均处于低危险区,现有防治工程可有效防治泥石流灾害;在50年一遇降雨频率下,丰河村处于泥石流高危险区,泥石流冲出排导槽,冲毁平松路,现有防治工程不能满足要求。采用多级拦挡坝、排导槽截弯取直等改进的防治工程后,可有效预防泥石流对沟口下方承灾体的损害,泥石流堆积方量减少50.2%,堆积面积减少86%,高危险区均位于排导槽内,治理效果显著。

2001—2022年陕北黄土地区地质灾害时空分布及引发因素分析

基于陕西省2001—2022年地质灾害资料,分析研究了榆林和延安22年来黄土地质灾害的时空分布规律和引发因素,并提出了防治措施建议,对陕西省乃至西北黄土高原地质灾害防治工作提供了可借鉴的依据。①在空间上重灾区呈弧形分布,主要在榆林的清涧县、绥德县、子洲县以及延安的宝塔区、安塞区、志丹县。地质灾害主要发育在丘陵区,支流两岸和河流交汇处。②在时间上主要发生在冻融季节和汛期,其中3月和7—10月是地质灾害高发期,而以7—8月为集中暴发期、产生的灾害最为严重。③降水和人工切坡是引发地质灾害发生的主要因素。④防治上,榆林、延安每年3月与汛期7—10月是重点防范期,弧形带是重点防范区,应加强巡查排查、监测预警、综合治理、宣传培训等综合防治措施;榆林前5d累计降水量在76 mm左右、预报降水量在37 mm时,延安地区前5d累计降水量在79 mm左右、预报降水量42 mm时,发出预报预警。

ArcGIS在湖北省公路地质灾害危险性评估中的应用

湖北省地处三大地质构造之间的交汇处,地形地貌、地质构造条件复杂多样,是我国地质灾害多发省份之一。运用ArcGIS软件对湖北省公路地质灾害进行危险性评估分析,根据评估结果对不同区域的诱发因素以及常见地质灾害进行论述,针对常见的地质灾害及其特点提出一系列针对性的防治建议,为湖北省公路地质灾害的防范治理提供依据。

新疆某露天矿山地质环境特征及评价

矿产资源是现代社会发展的重要动力,在人类进行开发的过程中,矿山及周边的地质环境遭受到破坏是难免的。在收集矿区的地质资料和现场勘探、调查数据的基础上,对矿区的地质环境进行现状评价、预测评价和综合评价。根据矿区内采矿活动对地质灾害、矿区下覆含水层的破坏、矿区原生地形地貌景观的影响及破坏、矿区地表水土环境的影响和破坏,以及矿区产生的大气污染等方面,对矿山地质环境特征进行总结,最后,根据地质环境的破坏程度提出相应的矿山地质环境防治措施。

煤矿地质灾害防治技术研究

在煤矿生产过程中,经常发生地压失稳、瓦斯爆炸、煤与瓦斯突出等灾害,直接影响到煤矿的安全生产。因此,煤矿地质灾害防治技术的研究,对于提高煤矿生产效率和安全性具有重要意义。首先分析了煤矿地质灾害的类型和特点,接着阐述了引起灾害的因素,最后探讨了煤矿地质灾害的监测技术、预防技术和治理技术,为煤矿企业的安全生产和发展提供了一定的参考。

区域性地质灾害综合防治系统研究

为了进一步解决我国区域性地质灾害防治工作中,因环节信息化技术水平低而导致的区域性地质灾害信息不能发挥最大作用的问题,本文依托鄂州市“四位一体、网格化管理”的地质灾害防治体系,结合当前先进的物联网、大数据、可视化、无人机等技术,研究并建立了区域性地质灾害综合防治系统,明确了综合防治业务流程。结果表明该系统能实现对地质灾害各环节信息的数据收集、分析处理、可视化展示,能够提升自然资源、应急管理等部门的地灾防治工作效率,增强区域地质灾害防治能力。

北京市门头沟区“23·7”强降雨引发地质灾害特征及防治建议

2023年7月29日20时至8月2日7时,北京出现极端强降雨天气,降水量为北京地区有仪器测量记录140年以来最高值,其中门头沟平均降水量达538.1 mm,最大降水量达1053 mm。本次强降雨引发多起地质灾害,对门头沟区生产生活造成了严重的影响。门头沟区“23·7”强降雨共引发地质灾害666处,规模以小型为主。其中崩塌592处,泥石流55处,滑坡10处,地面塌陷9处。崩塌灾害中岩质崩塌和土质崩塌大致相当,破坏类型以滑移式为主。滑坡灾害以土质滑坡为主,破坏类型均属于浅层牵引式滑坡。泥石流灾害以稀性泥石流为主,破坏类型均属于暴雨型泥石流。地面塌陷均由历史采矿引起,主要表现为塌陷坑、地裂缝等变形破裂。根据灾害现状地质环境背景及成因,综合考虑地质灾害风险等级、周边地质环境条件、工程治理可行性等,提出了“应急处置、群测群防、搬迁避让、工程治理”防治建议。

宜兴市地质灾害特征和防治工作研究

宜兴市地质环境条件复杂,影响地质环境的人类工程活动较强烈,地质灾害类型齐全,隐患点数量多、危害较严重。文章简述了宜兴市的地质环境条件和地质灾害发育分布特征,分析了地质灾害防治工作面临的形势,提出了地质灾害防治工作建议,为宜兴市地质灾害防治和地质环境保护工作提供了依据。

甘肃省地质灾害发育特征

甘肃省地质环境条件复杂,受极端天气、地震及人类工程活动等影响,区内地质灾害多发、频发,防灾减灾形势严峻。为进一步查清甘肃省地质灾害现状发育特征,在甘肃省1∶50000地质灾害风险调查最新数据分析的基础上,分析了全省地质灾害灾情险情特征、总结了地质灾害时空分布规律及致灾特征。研究结果表明:①甘肃省地质灾害以崩塌、滑坡、泥石流为主,灾害规模多为中小型;②在空间分布上,地质灾害主要集中分布于甘肃省中部和东南部的9个市州,属于黄河流域及黄土高原区、白龙江流域及陇南山地;③在时间分布上,5—9月主汛期是地质灾害高发期,以7月下旬—8月上旬最为严重;④地质灾害具群发致灾、隐蔽致灾和链式致灾特征。研究成果可为区域地质灾害风险管控和应急管理提供一定的技术依据和参考。

机载LiDAR技术在广州黄埔区地质灾害调查中的应用

近年来,机载LiDAR技术快速发展,其能够“穿透”地面植被,获取地面真实高程,对于精准获取地质灾害隐患点具有重要意义。为查明广州黄埔区地质灾害发育特征,文章基于机载LiDAR技术获取了黄埔区总面积为526.5 km^(2)的三维点云和数字正射影像等数据,结合传统人工现场调查手段,查明项目范围内的典型地质灾害发育特征。解译结果表明:调查区内地质灾害呈面状和线状分布,主要集中在中北部山区丘陵地带,其他地区零星分布或无分布,崩塌及危岩体类地质灾害435处、滑坡及不稳定斜坡类地质灾害1027处,极端天气情况下可能诱发的低频泥石流灾害66处,以滑坡及不稳定斜坡类灾害为主;此外,区内地质灾害发育规律与地形地貌、地质条件、工程活动及降雨等因素具有较强的关联性,其中降雨诱发地质灾害较为显著,灾害多发生在月降雨量650~700 mm区间。研究表明,机载LiDAR技术能够实现研究区内地质灾害的识别,对指导识灾避灾减灾工作具有较好的指导作用和应用价值。

论线状工程地质灾害预防应对问题

线状工程地质灾害预防应对工作要考虑工程全寿命周期的安全问题,具体划分为规划选线、设计施工和工程运营三个阶段分别考量并制定针对性对策。规划选线阶段主要是规避地质灾害风险,设计施工阶段主要是采取工程措施预防可能遭遇或引发的地质灾害,工程运营阶段主要是监测预警和高效处置可能发生或正在发生的地质灾害。