Landslide Mitigation Research Articles

Landslide susceptibility analysis of Karakoram highway using analytical hierarchy process and scoops 3D

Landslides are prevalent, regular, and expensive hazards in the Karakoram Highway (KKH) region. The KKH connects Pakistan with China in the present China-Pakistan Economic Corridor (CPEC) context. This region has not only immense economic importance but also ecological significance. The purpose of the study was to map the landslide-prone areas along KKH using two different techniques-Analytical Hierarchy Process (AHP) and Scoops 3D model. The causative parameters for running AHP include the lithology, presence of thrust, land use land cover, precipitation, and Digital Elevation Model (DEM) derived variables (slope, curvature, aspect, and elevation). The AHP derived final landslide susceptibility map was classified into four zones, i.e., low, moderate, high, and extremely high. Over 80% of the study area falls under the moderate (43%) and high (40%) landslide susceptible zones. To assess the slope stability of the study area, the Scoops 3D model was used by integrating with the earthquake loading data. The results of the limit equilibrium analysis categorized the area into four groups (low, moderate, high, and extremely high mass) of slope failure. The areas around Main Mantle Thrust (MMT) including Dubair, Jijal, and Kohistan regions, had high volumes of potential slope failures. The results from AHP and Scoops 3D techniques were validated with the landslides inventory record of the Geological Survey of Pakistan and Google Earth. The results from both the techniques showed similar output that coincides with the known landslides areas. However, Scoops 3D provides not only susceptible zones but also the range of volume of the potential slope failures. Further, these techniques could be used in other mountainous areas, which could help in the landslide mitigation measures.

GEOLOGICAL STRUCTURE ANALYSIS FOR POTENTIAL LANDSLIDE DISASTER AND MITIGATION AT TANJUNG KERAMAT AREA, GORONTALO

Geological structures in the form of joints and faults have big role in landslide disaster. This study aims to analyze the geological structures using stereographic analysis and rosette diagrams and determine the potential landslides that can occur in the research location in order to identify landslide mitigation efforts in the research area. The method used in this research is field observations then followed by stereographic analysis and rosette diagrams, which are one of the diagrams of the presentation of orientation of the geological structures elements. The results showed that the mechanism of landslide mostly caused by the geological structures distribution in the Tanjung Keramat area, especially by joint distribution. Tension joints dominant direction relatively west as well as the slope direction. Stereographic analysis of the shear joints show the type of extensional stress directing relatively North-South. Potential types of landslide that can occur are wedge failures. Appropriate mitigation efforts are by reducing the slope angle and making structural retaining walls to withstand natural slopes and heaps high enough.

LANDSLIDE SUSCEPTIBILITY MODELLING IN SELECTED STATES ACROSS SE. NIGERIA

Identification and mapping of landslide is essential for landslide risk and hazard assessment. This paper gives information on the uses of landsat imagery for mapping landslide areas ranging in size from safe area to highly prone areas. Landslide mitigation largely depends on the understanding of the nature of the factors namely: slope, soil type, lineament, lineament density, elevation, rainfall and vegetation. These factors have direct bearing on the occurrence of landslide. Identification of these factors is of paramount importance in setting out appropriate and strategic landslides control measures. Images for this study was downloaded by using remote sensing with landsat 8 ETM and aerial photos using ArcGIS 10.7 and Surfer 8 software, while Digital Elevation Model (DEM) and Google EarthPro TM were used to produce slope, drainage, lineament and elevation. From the processed landsat 8 imagery, landslide susceptibility map was produced, and landslide was category into various class; low, medium and high. From the study, it was observed that Enugu and Anambra state ranges from high to medium in terms of landslide susceptibility, Imo state ranges from medium to low.

Real-Time Diagnosis of Island Landslides Based on GB-RAR

Landslides are one of the most frequent and serious geological disasters that threaten people’s lives and property safety. In recent years, with the rapid development of the coastal economy and the increasingly strained spatial resources, the island development activities have become extremely rapid, resulting in the frequent occurrence of landslides on the island. We selected Beichangshan Island in the north of China as the research area. By using high-precision ground-based real aperture radar (GB-RAR) measurement technology, the displacement changes of potential landslides are monitored continuously and dynamically to realize the real-time diagnosis and early warning of island landslides. At the same time, the data interpretation method and key processing flow are described in detail. The results show that during the whole monitoring process, an area of obvious change is found, which is mainly located in the middle of the landslide mass. The mean velocity rate shows a nonlinear deformation trend. The maximum deformation of the landslide in the five selected points reaches 4.5 mm, which indicates that the area is in an unstable stage. The deformation monitoring ability of GB-RAR technology to identify the sub-millimeter level is demonstrated, and the monitoring method is verified. The validity and reliability of the method can be applied to real-time dynamic fine deformation diagnosis of island landslides. Its accuracy can meet the needs of dynamic change monitoring of island landslides, and it can become an important tool and means for early warning and treatment of landslides. The research is conducive to further enriching and improving the monitoring method system of island geological disasters in China, provides a scientific basis and technical support for early warning and disaster prevention and mitigation of island landslides, and can be popularized and applied in the monitoring of island landslides.

Quantitative Risk Analysis of a Rainfall-Induced Complex Landslide in Wanzhou County, Three Gorges Reservoir, China

On 4 April 2013, a 1.5 million cubic meter landslide occurred in Sunjia Town, Wanzhou County, Three Gorges Reservoir, China. After initiation, the Sunjia landslide traveled about 30 m toward the northeast and destroyed most of the infrastructure in its path. The landslide was triggered by heavy rainfall and previous slope excavations, but this slope also displayed a complicated failure process: the overlying earth slope first deformed and then induced sliding along underlying rock surfaces. Surface displacements that resulted from continuous creeping of the post-event slope were observed by an emergency monitoring system that revealed the disequilibrium state of the slope. To discuss the stability and future movements of the remaining unstable debris deposits, we developed a geotechnical model of the post-slide slope, calculated how it can slide again in an extreme rainfall scenario, and estimated the potential runout distance using the Tsunami Squares method. We then estimated the number of people and the value of the infrastructure threatened by this potential landslide. Lastly, we analyzed the vulnerability of elements at risk and quantitatively evaluated the hazard risk associated with the most dangerous scenario. This quantitative risk analysis provides a better understanding of, and technical routes for, hazard mitigation of rainfall-induced complex landslides.

Farmer’s perception and knowledge on landslide occurrences in Beruk Village, Karanganyar Regency, Central Java

Karanganyar Regency is one of the most prone area to landslides in Central Java. According to DIBI records, 77 of the 149 types of natural disasters that occurred in this area were landslides during 2008-2018 and the trend tends to increase. In disaster management, the ability of the community to reduce the risk of landslides is reflected in capacity. The objective of this study is to know the farmers understanding on landslide factor, landslide occurrences and impact, and landslide mitigation in Beruk Village, Karanganyar Regency. The data was collected by interview to 109 farmers household, and the analysis was conducted by descriptive analysis. The result shows that the landslide is mostly caused by heavy and long duration of rain, indicator for landslide is ground cracks, and the mitigation mechanism is based on local knowledge of farmers such as managing irrigation system, planting trees, and managing land utilization. In Beruk Village, disaster management process is more to be responsive rather than preventive and the knowledge of farmers on land management play an important role in disaster risk reduction.

Displacement Prediction of a Complex Landslide in the Three Gorges Reservoir Area (China) Using a Hybrid Computational Intelligence Approach

Displacement prediction of reservoir landslide remains inherently uncertain since a complete understanding of the complex nonlinear, dynamic landslide system is still lacking. An appropriate quantification of predictive uncertainties is a key underpinning of displacement prediction and mitigation of reservoir landslide. A density prediction, offering a full estimation of the probability density for future outputs, is promising for quantification of the uncertainty of landslide displacement. In the present study, a hybrid computational intelligence approach is proposed to build a density prediction model of landslide displacement and quantify the associated predictive uncertainties. The hybrid computational intelligence approach consists of two steps: first, the input variables are selected through copula analysis; second, kernel-based support vector machine quantile regression (KSVMQR) is employed to perform density prediction. The copula-KSVMQR approach is demonstrated through a complex landslide in the Three Gorges Reservoir Area (TGRA), China. The experimental study suggests that the copula-KSVMQR approach is capable of construction density prediction by providing full probability density distributions of the prediction with perfect performance. In addition, different types of predictions, including interval prediction and point prediction, can be derived from the obtained density predictions with excellent performance. The results show that the mean prediction interval widths of the proposed approach at ZG287 and ZG289 are 27.30 and 33.04, respectively, which are approximately 60 percent lower than that obtained using the traditional bootstrap-extreme learning machine-artificial neural network (Bootstrap-ELM-ANN). Moreover, the obtained point predictions show great consistency with the observations, with correlation coefficients of 0.9998. Given the satisfactory performance, the presented copula-KSVMQR approach shows a great ability to predict landslide displacement.

Landslide disaster mitigation plan in Karang Tengah Village, Bantul district, Yogyakarta

Karang Tengah Village is one of the villages that are vulnerable to landslides that located on the topography of the ridge to the hills in the eastern region of Bantul Regency. Based on the map of landslides incident from the Regional Disaster Management Agency in 2011, Karang Tengah Village has steep slopes, so it has a high potential for landslides. One way to mitigate landslide disaster is to assess and analyze the risk of landslide disaster in detail. This study aims to identify the homes of residents who are in the landslide threat zone, be it a high or medium threat zone. The method used in this research is descriptive method with qualitative approach combined with a quantitative method used to give a clear picture of the number of houses in each zonation. Sources of data used are primary and secondary data sources through interviews and documentation. The results of this study indicate that 1) the number of households in the high-risk zone is 63 houses, in the yellow risk zone is 59 houses. 2) The village of Karang Tengah has a high threat, medium to high vulnerability, and medium capacity, which means having a medium to high risk. 3) Recommended infrastructure.

Establishment of Asia-based Research Center for Mitigation of Landslide and Flood Disasters by Japan-Vietnam Joint Initiative

Establishment of Asia-based Research Center for Mitigation of Landslide and Flood Disasters by Japan-Vietnam Joint Initiative

Castanea sativa Mill. plantations as a low-carbon landslide hazard mitigation measure

In the last twenty years, several rainfall-induced landslides occurred in areas surrounding Mount Vesuvius (Campania, Italy). Landslides usually involve the shallow pyroclastic soil layers (2-3 m thick) covering the steep slopes of the Lattari Mountains. The cultivation of trees for fruit production on the pyroclastic cover is a common practice by local farmers. Woody vegetation contributes to slope stability through the mechanical reinforcement of soil by roots. We investigated the use of Sweet chestnut (Castanea sativa Mill.) trees as a low-carbon landslide mitigation measure to be applied in large areas where conventional geotechnical engineering solutions would be costly and extremely invasive, in order to respond to the demand in energy and environmental geotechnics for eco-friendly approaches. The root distribution of C. sativa in terms of root volume ratio was determined from soil cores. The mechanical reinforcement of soil by tree roots was quantified based on root-soil interaction models. Slope stability was analysed by means of limit equilibrium analyses performed on an infinite slope. The safety factor calculated for a cultivated slope was higher than for a fallow slope due to the mechanical reinforcement provided by roots. Therefore, the cultivation of C. sativa is a useful mitigation measure against shallow landslides.

Proposal of a simplified method for verifying the effectiveness of landslide mitigation measures

Proposal of a simplified method for verifying the effectiveness of landslide mitigation measures

Predicting landslide susceptibility and risks using GIS-based machine learning simulations, case of upper Nyabarongo catchment

Sustainable landslide mitigation requires appropriate approaches to predict susceptible zones. This study compared the performance of Logistic Model Tree (LMT), Random Forest (RF) and Naïve-Bayes Tree (NBT) in predicting landslide susceptibility for the upper Nyabarongo catchment (Rwanda). 196 past landslides were mapped using field investigations. Thus, the inventory map was split into training and testing datasets. Fifteen predisposing factors were analysed and information gain (IG) technique was used to analyse the correlation between factors and observed landslides. Therefore, the area under receiver operating characteristic (AUROC) with other statistical estimators including accuracy, precision, and root mean square error (RMSE) were employed to compare the models. The AUC values were 78.7%, 80.9% and 82.4% for RF, LMT and NBT models, respectively. Additionally, the NBT produced the highest accuracy and precision values (0.799 and 0.745, respectively). Regarding RMSE values, the NBT model achieved an optimized prediction than RF and LMT models (0.301; 0.428 and 0.364, respectively). The results of the current study may inform further studies and appropriate landslide risk reduction and mitigation measures. They can also be instrumental for policy and decision making in regards with natural risk management.

Model of Physics Landslide for Disaster Mitigation in Sitinjau Laut Area Padang City Sumatera Barat

Sitinjau Laut area of Padang city is very prone to landslides because it has a very steep terrain (70º to 85º), improper land use and high rainfall. In the context of investigating potential landslides in this region, landslide potential analysis was carried out in five locations with a rating method for seven variables; slope, soil and rock structure, effective soil depth, rock weathering level, land use, vegetation density and rainfall. The total value of each location is, the first location has a total value of 26 with a category of severe landslide potential, the second location has a total value of 26 with a category of severe landslide potential, the third location has a total value of 24 with a category of severe landslide potential, the fourth location has a total value 21 with a moderate landslide potential category and the fifth location has a total value of 22 with a moderate landslide potential category. It is hoped that this research can provide input to the Regional Government in the context of landslide mitigation in the region. So that the risks posed by landslides can be minimized for the future.

The September 16, 2017, Linjiabang landslide in Wanyuan County, China: preliminary investigation and emergency mitigation

This paper reports on a typical slow-moving landslide that occurred in Shuitianba village in Wanyuan County, Sichuan Province, China, on September 16, 2017. The landslide in Wanyuan County is regionally outstanding for its features and well-developed landslide morphology. Hence, this event can provide a good case study for understanding the possible triggering conditions of the occurrences of all the landslides examined in Wanyuan County. The 225 residents of Shuitianba village did not flee the village because the deformation of the landslide was extremely slow. However, the primary emergency tasks are still necessary to reduce the landslide risk that may affect the residents. Detailed field investigations, boreholes, and exploratory trenches were performed to investigate the characteristics and triggering factors of this landslide. Rainfall and anthropogenic activities (such as informal, unplanned settlements and deforestation) were revealed to be the main triggering factors. The main engineering control measures, including anti-sliding piles, an anti-sliding retaining wall, and intercepting ditch, were applied to stabilize the landslide. However, landslide mitigation measures have not been finished, and hence, some interim measures are suggested to effectively reduce landslide risk.

Slip surface identification based on engineering properties analysis of weathering breccia at landslide occured in mount pawinihan, central java, indonesia

Landslide mitigation may be performed in various methods, such as by identifying the weathering degree in order to determine the position of slip surface. Slip surface is imaginary plane beneath surface dividing the moving part of slope mass with the rest, In short, it may also be defined as the weakest zone where the landslide may occur. Therefore, slip surface is the main object of this research which result may be used as a reference for further mitigation step. This research is conducted in the landslide case of Mount Pawinihan, Banjarnegara. The research is conducted by identifying the weathering degree of heterogenic material based on the British Standard EN ISO 14689-1. Engineering properties sampling was conducted after identification of weathering zone and use systematic sampling base on zone of weathering. The research result shows that the landslide soil mass under study may be divided into four weathering zones exposing on surface, while the position of slip surface may be identified in the weathering zone 3 (moderately weathered). This zone is a boundary of rock and soil condition.

Design of Early Warning System Flood and Landslide Mitigation Sensor Based on Internet of Thing

Disaster mitigation is very important in order to reduce the number of victims of both life and material. Alertness in disaster mitigation is urgently needed in every area in all countries of the world, especially in Indonesia. Embedded device technology specifically designed and programmed to detect disasters such as earthquakes, tsunamis, floods and landslides, storms and hurricanes. The sensors are used according to the type of disaster will be detected. The system will be built this serves as an early warning system that will provide early warning against floods and landslides were predicted would happen. The system can detect floods and landslides in accordance with a sensor mounted on a disaster-prone locations. Device technology development mitigation sensors embedded as floods and landslides integrate hardware and software and Internet networks. Hardware in the form of microchip controllers and software applications of information and communication technology based internet of things. Microcontroller programmed so that it can control the data with computational algorithms can predict natural disasters will occur. With the development of technology these devices could be detected early disaster. For Embedded system could be produced more cheaply with a local content of 60%. This support government programs in the field of technological independence. Microcontroller programmed so that it can control the data with computational algorithms can predict natural disasters will occur. With the development of technology these devices could be detected early disaster. For Embedded system could be produced more cheaply with a local content of 60%. This support government programs in the field of technological independence. Microcontroller programmed so that it can control the data with computational algorithms can predict natural disasters will occur. With the development of technology these devices could be detected early disaster. For Embedded system could be produced more cheaply with a local content of 60%. This support government programs in the field of technological independence.

Landslide Mitigation of Banjir Kanal Semarang, with Grouting Method

Indonesia is aprone’s country to the occurrence of mass movements. These disasters often occur in various regions, especially during the winter. Banjir Kanal is one of the locations of landslides from the observation in the field, the type of ground motion that occurs in the research area such as slump, it caused by the intense weathering of rocks and triggered by a condition of ground water level, Vibration, and human activities. Soil material at the research area such as claystone as the original soil and sandy clay stone as fill soil. The soil conditions and slope angle that very steep about 60 degree is a factors causing mass movement. The purpose of this research to determine the type of ground motion, causes and triggers of mass movement at the research area, and to know the success level of grouting methods to overcome them. The research method that used is descriptive method and experimental methods. Slope stability analysis used by the Fellenius method that calculated to determine the value of safety factor (Fs) at the study site. Based on the results of such simulations could be seen that after the implementation of grouting, soil cohesion increased.

Sub Surface Active Fault Identification on Quaternary and Tertiary Rocks using Geoelectric Method in Cilaki Drainage Basin, Southern Part of West Java, Indonesia

The geophysical surveys are needed to obtain information on subsurface geology for infrastructure development, mitigation of landslide and geothermal. Cilaki drainage basin is an area Garut Regency at southern part of West Java. The area has complex geological and the main target in development plan of Southern part of West Java. The electrical resistivity method of the Schlumberger configuration was used to identify the geological subsurface and the active fault of the study area. The measurement of the electrical resistivity was made on 7 lanes (GL 1 until GL 7). The location has a height of 195 to 925 meters above sea level with depth reaching more than 120 meters and electrical resistivity value of 6 - 450 Ω meters. Generally, the electrical resistivity value of Quaternary rock units have value between 80 and 450 Ω meters and Tertiary rock unit have value of 6 - 40 Ω meters. Based on the results of data analysis can be interpreted that the area has been deformed. This is reflected also in the geomorphology as an indication of tectonic phenomenon in the form of active faults. Quantitatively, this is reflected in the value of the mountain-front sinuosity (Smf) index which ranges 1.036 to 2.173. This phenomenon occurs in geomorphology which is composed of Tertiary and Quaternary rocks.

Social Impacts of Landslide Disasters with Special Reference to Sri Lanka

Disaster call be explained as an occurrence disrupting the normal conditions of existence and, causing a level of suffering that exceeds the capacity of adjustment of the affected community. Any disaster event is tagged with tremendous impact to the society or community. Thus, Social Impacts of Landslides can be defined as "the consequences to human populations of any Landslide incident that alter the ways in which people live, work and spend their leisure time, relate to one another, organize to meet their needs and generally cope as members of society including changes 10 the cultural norms, values, and beliefs that guide and rationalize their cognition of themselves and their society ". Hence, any consequence caused as a result of a landslide, which eventually leads to alter the day to day life-styles, livelihood patterns, cultural integrity and social networks of affected family/s or a neighbourhood can be classified as a Social Impact. Scope of the Problem Of the 65,000 sq. kill of the land area of the island of Sri Lanka, nearly 12,000 kill spread over seven of its administrative districts are highly prone to landslides. Scientific studies have revealed that the frequency of landslides is on the increase particularly because of the unplanned intensive cultivation, nOI1 - engineered constructions, deforestation, neglect of land, and ever increasing human intervention. Although humans create and contribute to landslide events, they are also the sufferers of these dreadful events. This paper will focus on the Social Impacts of Landslide Disasters in Sri Lanka with special reference to May -2003 and January -2007 incidents in Matara and Nuwara Eliya Districts respectively. Objective of this paper is to explore the Social Impacts of Landslides with reference to Deaths, Displacement, Personnel & Social Insecurity, Health Issues, Issues of Women & Children, Psychological Reactions, Involuntary Resettlement, Legal Issues and Recovery & Reconstruction Needs. This paper includes information gathered and experiences gained from the research conducted among the May 2007 landslide affectedfamilies in the Deniyaya area of the Matara District and the field observations carried out among families that experienced similar disasters in mid January 2007 in Walapane and Hanguranketha areas of the Nuwara Eliya District of Sri Lanka. A Questionnaire Survey was carried out among the affectedfamiliesjust one week after the May-2003 landslides in the Southern Sri Lanka. In the Research Methodology techniques such as field observations. recording of case studies. collection of spatial data and geographical coordinations of the affected areas using Global Positioning Systems (GPS - MLR - SP24) were also used in this research headed by the author of this paper. in collaboration with several members of the academic staff and about 70 under graduates of the Department of Geography of University of Sri Jayewardenepura Sri Lanka. Field observations and informal interviews were conducted afew days after the January - 2007land5lide incidents in central Sri Lanka among the affected families and formal meetings were held with officials to collect information. Major Issues Addressed The population and social structures of the landslide affected areas were seriously affected mainly by the number of human deaths. During the period 1869 to 2003. there were about 178 reported landslides all over Sri Lanka. causing over 455 deaths. The impacts of landslides have worsened during the last 25 years and 85% of deaths have occurred during this period The worst ever landslide disasters in the history of Sri Lanka were reported in May-2003 with 188 deaths and 139. 000 displaced. Further, the landslides of January - 2007 in Sri Lanka have claimed 21 lives while over 4.200 have been displaced. In the past 25 years from 1982 to 2007 landslides have killed 403 persons and affected over 150.000 families while around 28 billion rupees (US$ 28 million) had been incurred on relief and reconstruction efforts. Landslide disasters in May-2003 were solely accountable for 96% of the above expenditure. Conclusion Social impacts of landslide disasters in Sri Lanka are immense and the effects more pronounced during the last 25 years. Thus landslide mitigation strategies that harmonize with the natural environment need to be implemented vigilantly in landslide prone areas.

KESEDIAAN MEMBAYAR MITIGASI LONGSOR DI KARANGANYAR DENGAN PENDEKATAN CONTINGENT VALUATION METHOD (Willingness to pay landslide mitigation in Karanganyar with the contingent valuation method approach)

Landslides are still a threat in some areas in Karanganyar Regency which has mountainous topography. Landslides cause in loss of property, and lives. Community participation in landslide mitigation is very important because the community is dealing directly with landslides. One of the roles of the community in landslide mitigation can be measured by the willingness to pay (WTP). The aims of this study are 1) to determine factors that influence WTP for reducing the impact of landslides, 2) to determine the value of WTP for landslides mitigation. The method used in this study is contingent valuation methods by calculating the amount of WTP to reduce the risk of landslides and the factors that affect WTP. This study used primary and secondary data. Primary data were obtained using open interview techniques with 100 respondents in some villages in Karanganyar District, who are at risk of landslides, while secondary data was taken from the Statistics Agency (BPS) and Regional Agency for Disaster Countermeasure (BPBD) of Karanganyar Regency. The results showed that incomes and poverty affected the WTP for landslide mitigation significantly. The average willingness to pay for landslide mitigation in the form of construction of cliff walls, closure of cracks and reparation of waterways in Karanganyar Regency is Rp. 26.307,00 per month.