Engineering geological investigation for landslide hazard zonation in the Sino-Nepal Road corridors.

Author(s):  
Basanta Raj Adhikari ◽  
Bingwei Tian ◽  
Feiyu Chen ◽  
Xiaoyun Gou ◽  
Suraj Gautam ◽  
...  

<p>Road construction in the Trans-Himalaya is always challenging task because of having fragile and rugged topography with the strong influence of monsoon. Three different road corridors namely Kaligandaki (Pokhara-Jomsoom-Zhongba), Trishuali (Kathamndu-Trishuli-Gyirong) and Bhotekoshi rivers (Kathmandu-Tatopani-Nyalam) cross the Himalaya with different geological discontinuities i.e. South Tibetan Detachment System (STDS), Main Central Thrust (MCT). The Himalayan range is acting a topographic barrier resulting different climate in the southern and northern part. These three roads are very strategic for the connectivity between Trans-Himalaya and midland. People have been living in these valleys for a long time. After the road construction, people have started to build houses along this road. However, people have are often forgetting the influence of these large scale mass movement that occurred in the past. Therefore, an attempt has been done to analyze these past events and their impacts. Preparation of engineering geological map, landslide inventories and investigation of large scale past mass movement have been done in detailed field investigations in 2018 and 2019 supported by remote sensing. Slope stability analysis has been done in different critical sections for the landslide hazard assessment. It is clearly seen that the road passes some of these large scale paleo-landslides and responsible for toe cutting. The road sections are critical in all three roads but more vulnerable in the southern slope of the Himalaya. The road between Beni to Larjung of the Kaligandaki has critical slope and susceptible for landslide occurrences. Therefore, proper mitigation measures have to be implemented for the stabilization of these mountain slope.</p>

2017 ◽  
Vol 15 (2) ◽  
pp. 110-127 ◽  
Author(s):  
Charles Teye Amoatey ◽  
Alfred Nii Okanta Ankrah

Purpose The purpose of this paper is to investigate the causes of road construction delays in Ghana and identify appropriate mitigation measures. Design/methodology/approach The initial approach involved an empirical analysis of 48 road projects to quantify the extent of time. This was followed by a survey of the perception of road agency and donor partner officials of the critical causes of road project delays. Findings About 70 per cent of road projects experience delays and 52 per cent experience cost overruns. The average time overrun and cost overruns of road projects in Ghana was 17 months and US$1.15m (or 22.5 per cent), respectively. The five most critical causes of road construction delays were delay in finance and payment of completed work by owner (client-related); inadequate contractor experience (contractor-related); changes in scope by the owner during construction (client-related); delay to furnish and deliver the site to the contractor (client-related); and inflexible funding allocation for project items (donor-related). Research limitations/implications The most critical constraint of this study is the fact that findings are based on only the views of industry professional experts. It may be assumed that despite using broadly used terminology to refer to the causes of project delays, the interpretations by respondents may have differed from those intended. Further research could look at the correlation between time overrun and cost overrun using principle component analysis. Practical implications The identified delay factors are not unique to the road sector. From both academic and practical perspectives, the results emphasizes on the need for a holistic and integrated risk management model for the entire construction industry in Ghana. Originality/value The paper examined the causes of road project delays in the Ghanaian context and recommended remedial measures.


2018 ◽  
Vol 4 (3) ◽  
pp. 265
Author(s):  
Emil Wahyudianto

Road corridor of Kota Batu – Kediri Regency Boundary is a provincial road that has a vital function for the economic and tourism movement from and to Batu City in East Java Province. This inter-regency road is historically vulnerable to disaster events such as landslide, Kali Konto flash flood, Kelud Mountain lahar, flood inundation, etc. This research was referred to Regulation of Ministry of Public Work No.22/PRT/M/2007 on Guidelines for Spatial Planning of Landslide Vulnerable Areas and helped with Geographic Information System (GIS). Method comparison was also conducted by Meiliana (2011) with the indicators from the same regulation, and by using Landslide Hazard Assessment (LHA) method that is based on historical data. The landslide risk mapping with LHA method that is combined with analysis result from the vulnerability of moving vehicles is suggested to be the reference in mapping the mass-movement disaster risk on Indonesian road corridors. Analysis on frequency of rainfall that triggered landslide concluded that the probability of landslide occurrence (PLO) on daily rainfall was 126.2 mm, or 3 days-cumulative rainfall of 192.26 mm.


2018 ◽  
Vol 27 (Supplement) ◽  
pp. 25-36 ◽  
Author(s):  
I.D.C. Hill ◽  
C.A. Rossi ◽  
S.O. Petrovan ◽  
M. Hartup ◽  
F. Clark ◽  
...  

The ever-growing pace of road construction worldwide has become a serious concern for wildlife and natural habitats, resulting in habitat fragmentation and increasing wildlife road fatalities. For amphibians, which are undergoing population declines worldwide, mitigation measures such as road under-passages linked to amphibian-proof fencing may be an effective conservation tool, aiming to reconnect natural habitats and reduce wildlife fatalities. This study assessed the efficacy of road tunnels in a recently developed area by Frankfield Loch, Stepps, North Lanarkshire. Three amphibian tunnels, plus fencing, were put in place during 2010 following the construction of a road in 2006 which separated the loch from a substantial area of marshland, including ponds. In 2015 and 2016, we used custom-made time-lapse cameras within the tunnels to automatically monitor amphibian movements and conducted frog spawn surveys. Numbers of common frogs (Rana temporaria), common toads (Bufo bufo) and newts (Lissotriton spp.) using the tunnels were substantial in both years, though the number of toads decreased significantly between years. We found many frog spawn clumps in the marsh ponds, but rather fewer in the loch. A period of road repair in 2015 was linked with both road mortalities and a change in the pattern of tunnel usage. Additionally, amphibians showed a daily cycle of activity, with nocturnal movements most common. These results indicate important connectivity and usage of both the marsh and the loch, and suggest that this can be effectively sustained through the proper maintenance of tunnels and fencing, which also minimises road mortalities. It remains unknown, however, what proportion of the population crosses the road via the tunnels and how that compares with movements prior to road construction.


2019 ◽  
Vol 58 ◽  
pp. 1-12
Author(s):  
Vinod C. Tewari ◽  
Victoria Z. Bryanne

Recent cloud bursts and Glacial Lake Outburst Flood ( GLOF ) in the Uttarakhand Himalaya have triggered catastrophic landslides. Heavy monsoon precipitation lashed Uttarakhand causing devastation and series of new landslides in the region. The Surbhi Resort Landslide is located near the hill station of Mussoorie in Garhwal Himalaya, India, in the Upper Krol Limestone. After intense rain in August 1998, the Krol sedimentary deposits suddenly gave way as a deep-seated landslide, blocking the main Mussoorie-Kemptyartery for 15 days. In 2005, the velocity of the slide was determined to be 4–14 mm/year by previous workers, thus it was still active with a modest intensity. Recently in 2018, during monsoon there was heavy rainfall in the Mussoorie and mud flow in the Kemty Fall area. Huge amounts of quaternary debris are still lying on the slope, another high intensity rainfall or cloud burst in future could trigger another large-scale failure. Based on our recent detailed investigations, following mitigation and bioengineering measures are suggested. To lower the ground water table, a series of horizontal drains should be installed at the base of the crown portion of the slide. This would generate an additional discharge which has to be channeled down Rangaon-ka-Khala, the natural channel, down the slope to the Aglar River flowing in the valley below. To prevent further surface erosion, it is suggested that the Rangaon-ka-Khalamust be bioengineered with shrubs and grasses such as Eriophorum comosum, Saccharum spontanum, Pogonatherum spp. And Wood fordia fruticosa while the surrounding slope must be reforested with Quercus leucotrichophora, Alnus napelensis , Pinus spp.and Cedrus spp. Check dams must be constructed on the entire 3.5 km stretch of the Rangaon-ka-khala to lower the velocity of thewater. This could be done either as gabions or in the form of live fascines of Salix tetrasperma or Dalbergia sissoo. The catchmentarea above the Mussoorie-Kempty road can be expected to collect 60,000 m3 in 24 hours in a 25-years reoccurrence cloud burst. Thus proper drains (0.40 m in dia.) on the inside of the road must be installed. The flow velocity at these extreme events would be 4.8 m/switch is slightly above the recommended value. If this water is allowed to flow down the Rangaon-ka-Khala it will most certainly lead to a major debris slide with a vertical velocity of almost 100 m/s with huge erosive power. For this reason, this discharge should be channeled down in plastic or cement lined pipes, preferably to the west of the Siyagaon Village which is reported as stable rather than in the landslide zone itself. It is concluded that these mitigation measures and bioengineering plantation would certainly help stabilize the Surbhi landslide area to prevent further disaster in future that destroyed the water mills, fields of the surrounding villages and mud flow in popular Kempty Fall area. These measures may also be applicable for the other active landslide zones in the NW(Jammu and Kashmir) and NE ( Darjiling-Sikkim ) Himalaya.


2019 ◽  
Vol 8 (9) ◽  
pp. 364 ◽  
Author(s):  
Xuequan Zhang ◽  
Ming Zhong ◽  
Shaobo Liu ◽  
Luoheng Zheng ◽  
Yumin Chen

The 3D road network scene helps to simulate the distribution of road infrastructure and the corresponding traffic conditions. However, the existing road modeling methods have limitations such as inflexibility in different types of road construction, inferior quality in visual effects and poor efficiency for large-scale model rendering. To tackle these challenges, a template-based 3D road modeling method is proposed in this paper. In this method, the road GIS data is first pre-processed before modeling. The road centerlines are analyzed to extract topology information and resampled to improve path accuracy and match the terrain. Meanwhile, the road network is segmented and organized using a hierarchical block data structure. Road elements, including roadbeds, road facilities and moving vehicles are then designed based on templates. These templates define the geometric and semantic information of elements along both the cross-section and road centerline. Finally, the road network scene is built by the construction algorithms, where roads, at-grade intersections, grade separated areas and moving vehicles are modeled and simulated separately. The proposed method is tested by generating large-scale virtual road network scenes in the World Wind, an open source software package. The experimental results demonstrate that the method is flexible and can be used to develop different types of road models and efficiently simulate large-scale road network environments.


Forests ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 1201
Author(s):  
Aristeidis Kastridis

The current review summarizes the knowledge generated by the recently published studies of the last twenty years, in the field of forest road networks, concerning the impact of forest road construction on hydrological processes. The currently applied methodology techniques/practices are discussed, the findings are highlighted and effective mitigation measures to mitigate the impact of forest roads are proposed. Critical for the minimization of the impact of forest roads on overland flow is the significant decrease in road surface runoff and overland flow velocity. The decrease in runoff energy reduces the detachment of soil particles and transportation in streams. The disturbances of forest roads in logging areas should be limited to decrease soil erosion. Additionally, aiming to minimize sediment transportation into the streams, it is very important to reduce the connectivity between the forest roads (or skid trails) and streams. The positive role of vegetation and organic matter on the road prism, naturally/technically established riparian buffers along the streams, and the use of appropriate bioengineering designs for each area significantly decrease the runoff generation and sedimentation. From a construction point of view, the decrease in short and long-term forest road-related impact could be achieved by reducing the depth of excavations and the use of soil compaction limiting technology during forest works. The road network design should be more efficient, avoiding hydrologically active zero-order basins. Techniques that minimize the length and connectivity among skid trails, unpaved roads and streams are highly crucial. Broad-based dips, immediate revegetation and outsloping of the road base are considered good road construction practices. Research should be focused on the hydrologic behavior of forest road networks and on the impact at the watershed scale, the degree of connectivity, utilizing plenty of qualitative field data, especially during intense rainfall events, which has been proven to exacerbate the runoff and sediment generation and transportation into the stream networks.


Symmetry ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1022 ◽  
Author(s):  
Alicja Sołowczuk

In road construction, environmental protection issues often become a challenge, both in the case of new routes and the existing network expansion projects. A number of specific issues are involved in severing of bat commuting routes and the relevant mitigation measures are still in the experimental stage. One of the measures are bat gantries installed on the established bat flyways aligned with the linear features of the landscape used by bats for echolocation calls, which is an example of the structures installed near Szczecin in Poland. The bat activity surveys revealed different levels of acceptance of the respective structures. The available studies identify the following factors as being relevant to relocated or modified commuting routes: road traffic volume, traffic noise, and light pollution. The article discusses which factors are the most likely to have a significant bearing on accepting specific structures by bats. The analyses show that a gantry structure can turn out to be acceptable to bats even on a completely new route if the landscape features are symmetrical and friendly to bats on both sides of the road and on both sides of their flyway as well. Conversely, without such a symmetry along the approach section, the structure may fail to perform.


2002 ◽  
Vol 26 ◽  
Author(s):  
M. P. Searle ◽  
R. L. Simpson ◽  
R. D. Law ◽  
D. J. Waters ◽  
R. R. Parrish

ABSTRACT Lithospheric convergence of India and Asia since collision has resulted in horizontal shortening, crustal thickening and regional metamorphism in the Himalaya and beneath southern Tibet. The boundary between the High Himalaya and the Tibetan plateau is a large scale, north-dipping, low-angle normal fault termed the South Tibetan Detachment (STD) which was active contemporaneously with the Main Central Thrust (MCT) bounding the southern margin of the High Himalaya. Previous studies have estimated minimum northward displacement along the STD of 35 km along the Everest profile. Here, we demonstrate approximately 200 km of southward displacement of footwall sillimanite + cordierite gneisses (minimum 90-108 km), formed at 600-630°C and pressures of 4.0-4.9 kbar ( 14-18 km depth), beneath the STD which acted as a passive roof fault during southward flow of the hot, viscous, ductile middle crust. U-Th-Pb dating of gneisses, sheared and cross-cutting leucogranites indicates that ductile shearing was active at 17-16 Ma, and later brittle motion at <16 Ma cuts all rocks in the footwall. High temperatures (>620°C) were maintained for -14 Ma along the top of the High Himalayan slab from 32-18 Ma, implying active crustal thickening and high topography in south Tibet during this time. The ending of metamorphism and melting in the Himalaya and ductile shearing along the STD coincides with the initiation of strike-slip faulting in SW Tibet and E-W extension in south Tibet.


2011 ◽  
Vol 261-263 ◽  
pp. 1119-1123
Author(s):  
Zi Jian Wang ◽  
Sheng Xie Xiao

This article in a typical road slope model as an example, through large-scale general-purpose finite element simulation software ANSYS/LS-DYNA rockfall on the slope of the roadbed impact for three-dimensional dynamic analysis in the roadbed, slope geological parameters and falling stone initial state is not at the same time on the roadbed impact the results of comparative analysis. The result is the mountain slope of the road construction project provides reference.


2020 ◽  
pp. 28-31
Author(s):  
Yucheol Shin

Little is known about the ecology of the Korean clawed salamander (Onychodactylus koreanus) but populations are declining due to human activities. We surveyed a mountainside road in the Republic of Korea and recorded the sex and life history stage of the salamanders crossing the road. Our results present the first evidence of mass movement in this species. We also show that road-kill is greater than estimated in previous studies. The males observed had fleshy hind-limb extensions and all females except one were gravid, indicating they were in reproductive condition and that mass movement of this species is probably linked to seasonal conditions and reproduction. Consequently, we argue that road kill may have a large impact on this species by eliminating reproductive adults. We call for road-kill mitigation measures on mountainside roads and further research into the migration patterns of this species.


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