| Sajha.com Archives | |
| Username | Post |
| GP | Posted
on 16-Aug-03 12:13 AM
Krishna Bhir: from Air In last March, Department of Roads organized an international symposium (something on landslide ...................) and I was one of the technical paper presenter at the symposium. The last 2 Transparencies that I presented at conference created a sensation inside that conference hall and immediately I got response from various top level officer at DOR. In those 2 OHP-T sheets, I talked about the solution to chronic problem of Krishna Bhir......... For me it was successful conference, because the project chief (Nepal side) of Banepa-sindhuli requested me to give a one day visit with an enginer. Well, I also pointed out the possible sites of Krishna Bhir like landslides, but, japanese have avoided sharp cuttings along Banepa-sinduli road, that was interesting part to me. When I read news and talk to people in Nepal, the Krishna Bhir again started to give "dukh" to my fellow citizens and all those solutions forgotten --though a senior official told me that he will try with my proposal--. What can I do? A photogrph I took during my flight to Pokhara is attached here for Sajhaities information. A good friend of mine, said he proposed to divert the whole road section to other side of river. i.e. build two bridges before the slope starts and after the slop ends.(you can see and feel). As a citizen of Nepal, what and how would you like us (engineers: using the tax paid by you) to solve this problem. ........... ............... I wish Krishna Bhir does not turn out to be "magi khane bhado". Well, a short description Banepa-Sindhuli road will be published in JSCE'S newsletter that circulates about 40,000 copies (every month: monthly issue). I will be a co-author of the paper. It will be in Japanese (translation) and in overseas section............ Those in Japan, happy reading the article. GP 
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| gunda | Posted
on 16-Aug-03 02:03 AM
I am not an engineer or expert on this field. Just from looking at the picture, it appears to be a flawed design that requires lots of money to correct it. Easiest and prudent solution would be to avoid landslide area all together and take the road to other side of the river where it appears to have some habitation and fertile land. An access provided by the road will bring commerce and other benefits to both side of the river. Of course this will cost more money to build bridges. Probably half the budget of the whole project but I think its worth it. Landslide area should be avoided as much as possible. Retention wall to prevent landslide in vertical hill is not going to work especially when topography has been already raped by slides and it has no cloths on to guard threatening monsoon rain. It will long rehabilitations to gain its strength back. I am not sure what you meant by you dont want this to be a begging bowl, if some guys have an wit and intellect and successful on making this begging bowl, whats wrong, it may not immediately solve the problem but at least money is coming into the country and people are employed??? |
| Bhunte | Posted
on 16-Aug-03 05:20 AM
gunda said "............Easiest and prudent solution would be to avoid landslide area all together and take the oad to other side of the river where it appears to have some habitation and fertile land............" I stand behind this idea. I was talking same last week with a nepali. If krishna bhir is a chronic problem, it may be cheaper to take the portion of road to the otherside. Otherwise, krishna vir will turn into milching vir of few handful people of nepal. |
| Arnico | Posted
on 16-Aug-03 09:43 AM
Hi...for the sajha engineers: here is another Krishna Bhir photo, taken in late May 2003. 
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| Arnico | Posted
on 16-Aug-03 09:49 AM
And here is another one. 
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| Arnico | Posted
on 16-Aug-03 09:51 AM
Sorry about the difference in color tones. The photos were taken a few seconds apart (on a Pokhara-Kathmandu flight), with a digital camera, through a not very clean window... so I tried to manipulate colors and contrast a little in order to bring out details (but forgot to check the photos against eachother for consistency). |
| Arnico | Posted
on 16-Aug-03 10:13 AM
Looking at the photos, I can see only two solutions for Krishna Bhir: 1) Blast (or bulldoze) away the whole hill side above the road...(similar to what was done at a landslide just upriver of the Kulekhani dam). 2) Build the two bridges as proposed. It is not just a matter of tax payer money spent, but of janta's money (and confidence) saved by having a reliable road link. Of course I'd hope that the bridges would be built to withstand large floods on the Trisuli ... I am hoping that the lessons of Malekhu Khola have been learned by now. Building a larger more expensive bridge higher up saves more money in the long run than building three permanent (and two temporary) bridges at the same site. Meanwhile, come to think of it... does any one know how high the risk of a GLOF is in the Trisuli valley? (GLOF = glacier lake outburst flood). There are a number of glacier lakes in the Langtang-Gosainkunda area, and perhaps (I don't have a satellite photo handy at the moment), also on the Bhote Koshi on the north side of Langtang Lirung. My sense is that a GLOF could wipe out several large sections of the Prithivi highway, as well as likely take with it the Dhading road bridge near Malekhu and the Manakamana cable car station... which gives us all the more urgency to have an alternative good road link between the Tarai and Kathmandu completed soon. Which makes me wonder... can anyone familiar with the Sindhuli road enlighten me as to WHY such an important road was built to be so narrow and unnecessarily curvy? I've only been on the first section of hte road, from Dhulikhel to Kabhre Bhanjyang, but was very surprised to find the road to be barely 5.5 meters wide (between drainage ditches)... and extremely curvy... when it would only have raised the construction budget by a few percent to move a little more earth, make the road a few meters wider, reduce a few curves, and increase the design speed by 20-30 km/h on large sections. Of course there will always be tricky sections where the road has to be narrower, and the driving speed slower... but WHY does a road of such importance get built for driving speeds of only 30-40 km/h? Why not build it of the current Prithivi Highway standard to start off with (60-80 km/h driving speed, wide straight lanes in each direction, with a wide enough shoulder to serve as a breakdown lane)? As soon as the eastern Tarai traffic picks up, and the road generates more eastern-Tarai to Kathmandu commerce, the road will be too narrow... and large sections of the drive on that road will involve being stuck as part of a slow-moving truck's long "tail' of vehicles who can't overtake because the road is too narrow to overtake the truck without going into the lane of vehicles moving in the opposite direction. The Dhulikhel-Sindhuli road will have to be widened/re-built within at most a decade of its opening. That will cost MUCH more than building it wider from the start. Is anyone familiar with the decision making process that chose the design standards that were implemented? |
| sparsha | Posted
on 16-Aug-03 10:21 AM
Blasting probably is cheaper than making two bridges. What about a tunnel ? just for that portion? Is it reasonable? I am not an engineer, must admit. |
| core_dump | Posted
on 16-Aug-03 11:44 AM
does anyone know any websites that are related to geography of nepal or where I can find satellite pictures of nepal. thank you. |
| DWI | Posted
on 16-Aug-03 11:52 AM
I haven't visited the site and don't have civil engr. experience so my thoughts shouldn't be counted as technical analysis. But logical thinking suggests that construction of bridge might mean a very temporary solution, which won't be cost effective in a long run. Looking at the site pictures and inclination of the hill, and also considering the fact that the hill's composition is similarly distributed (soil being landslide prone, roots not holding them), it is highly possible that another landslide of the same nature can occur, in the proximity. Foundation of any bridge in the landslide affected ground (obviously one end of each bridge should be built near the hill), can also be questioned. Idea on tunnel might also be expensive as a very strong tunnel to withstand any future effect by sliding surface should be built. Arnico's questions are completely valid and it makes you think if even these roads went through any pre-site survey during construction or not. Nice article GP, is that newsletter distributed overseas (US) too? |
| gunda | Posted
on 16-Aug-03 02:06 PM
I have my reservation on blasting off the whole hill, its effect would further degrade the critical environment and its impact will seriously undermine the whole purpose. All the debris from the blasting the hill will have to be dumped in to the river, which will change the course of the river, which will forced the river to claim the whole pristine piece of land at the other side of the river. I have no knowledge on the mechanics how road building and how the process work, except some friends who have been involved in such projects and they seems to suggest that its the government and political bureaucracy that is responsible for sub-standard roads, bridges and dams. Whenever there is a big project like the Sindhuli road, politicians will have to get their cut of the project kick backs- they are the one who appoint engineers, contractors and suppliers. Its cascading effect, because contractors and engineers have to give kickback to the, they will have to cut corners and use sub-standards materials and equipment to save money. If the engineers refuse to comply with their demands will be replaced will by someone who will. Its basically whom you know and what you are willing to do to save your job out here. I have a theory that roads are intentionally made curvy to prolong the project to milk funds as much as possible. Once the Engineers and bureaucrats make an alliance, they can do whatever they dont have to answer to no one. They have no regards to the people and country and how it will affect the Nepal with higher usages of fuel that all has to be imported by land and how it will impact on the productivity of the people when travel takes seemingly longer than it should. I would summon Maoist to take of these endemic problems in Nepal; they are the only party that seems to be honest at the moment. |
| GP | Posted
on 16-Aug-03 03:23 PM
Here is one immediate temporary and cost effective solution: 
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| GP | Posted
on 16-Aug-03 03:25 PM
Other sites that might suffer landslide in near future: 
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| Sadabichar | Posted
on 17-Aug-03 01:45 PM
Revegetate the sliding area from top to bottom. You might require a very large wire-mesh to cover the whole exposed portion, even extend the wire-mesh beyond that area's boundary to integrate seamlessly with near by areas. Then spread the cohesive clayey soil layer on the top of the mesh, lay sods on the top of that... the grass must be high quality, strong one. Have it done all during non-rainy season.. and supplement all the best requirement for the grasss to grow there... Later you may plant the trees which grows thier roots deep inside in the ground. Well, somehow revegetate the area.. that;s the main idea here. |
| kiddo | Posted
on 17-Aug-03 02:02 PM
You must be kidding me. Revegetate? Didn't you see vegetatoin already in the nearby area? Grass to hold landslides? Please, trees may be. And the hill already has trees. Besides you want people to go vegetate the whole area depicted in picture as someone brought out the point that landslide can occer in other area nearby too. And even that won't fix the problem. Revegetation is a solution for landslide but not in a critical time like this and critical situation as it is. Please think 5 times before you post such suggestions. This is only for Sadabichar, other suggestions were well thought. |
| Sadabichar | Posted
on 17-Aug-03 10:04 PM
This is the problem with our Country... people come up with hi-fi idea imposing high-budget costly solution to the problem. It's afterall mentality and vested interest of the parties responsible for solving the problem. Yeah, they will surely recommend costly solutions, no doubt about it. |
| Sadabichar | Posted
on 17-Aug-03 10:06 PM
Janata ta sojha chhan ni hamro desh ma... Je Bhandiye ni hunchhe tini hurlai... Thula Bada ra pade lekheka le nei ta paisa kamaune pratha paryo.. bottom line is this. |
| GP | Posted
on 18-Aug-03 02:49 AM
Sadabichar and kiddo, I could not understand your last 3 postings. Vegetation is environmentally and aesthitically a very good solution. ITs what we were discussing last week in Singapore (12th Asian Regional Conference on Soil Mechanics and Geotechnical Engineering). Panelists in the special TC-9 session were interested to know more about vegetation as next generation solution to slope stability problem. Well, a good friend of mine who is doing Post Doc in our univ. is expert in vegetation as a slope stabilization and he is writing a book in Nepali. I am "proof" reading the book and it was his part of thesis work. In his Ph.D. thesis had classified 4 types of roots. He indeed did pilot test in Nepali mountain slopes and found that vegetatation has several effects: good filtering, decrease in water flow speed, and reinforcement. ...... So, vegetation is indeed an ultimate solution to poor country like Nepal. In fact, if Krishna bhir can be terraced and on flat part if vegetation can b e planted, it will be stable solution. There is no doubt. But, it takes time before vegetation start sharing the stabilization parts. Until than, we need another supplimentary method...... One more thing we have to note is that the length of slope is more than 250m and its really a long slide. The main problem I see from picture posted by Arnico is that there is a gullie and water might have percolated and pore pressure increased around the bottom or suface triggering the slope failure. IF the percolating water can be bypassed, and surface can be kept dry the creep can be avoided and other permanent solutions can be used taking time. Bridge constrcution is a good solution, but, its really costly. Other solution is blasting the slope making it less steep. (this is idea, but, nepali mountains are too steep and blasting can not be permanent solution. Blasting may make the slope further unstable. There are many other costly solutions: e.g. soil anchoring, soil nailing, reinforced earth .... gabion wall, geosynthetic walls, concrete/masonaryh retaining wall.... What we should understand is that there are two stabilities we need to check. Internal stability and external stability. .................... I don't want to go into full detail of what IS or OS are, but, the geologists tell that deep sheeted slide is main reason.... while civil engineers will say its because of pore pressure rise during heavy rainfall and the weathered zone failed ................. What I understand is that without having a drilled data, we will not know what is happening inside the slope. Drilling is equivalent to stool and urine test in hospitals. Geophysical refractions can be like ultrasound test in human body. So, before you impelment a permanent solution, we need to know what is happening inside the body. Quack doctor may right prescription when you sit infront of him, but, a professional doctor will start from extreme and come up with regular walking excercise as a solution to the problem you have in your body...... So, I will suggest first temporary solutions and terracing is cost effective temporary solution. GP |
| Kiddo | Posted
on 18-Aug-03 04:30 AM
GP If you read my posting, I didnt' say vegetation is not an alternative for slide prevention. I said it cannot be counted as the immediate solution. 1st it is gonna take a while to terrace the Krishna bhir & grow right vegetation, besides they have noted earlier that other parts of the hills are prone to the landslide too. Consider a scenario. An illiterated terrorist is going to blow up a school as he hates education. Are you going to put the terrorist into 12 year education program at this moment now? If I confuse you, thank me. |
| paachak | Posted
on 18-Aug-03 05:49 AM
healthy discussion, What about tunnel as suggested earlier? Countries in Europe and Japan have many tunnels in the hills where they really do not need such infrastructures. Why can't we make tunnel in Krishna Bhir? What's wrong there in the geological properties of hill? Why can't we make tunnel? Is it only a money problem or political or technical? Sorry, if it does not make sense to you. |
| sadabichar | Posted
on 18-Aug-03 07:19 AM
Good to know that our guys are doing PhD research on Vegetation as a mitigation technique for the slope stability. I am happy to hear that!!! |
| thaag | Posted
on 18-Aug-03 07:25 AM
To Core Dump Are you looking for satellite pictures? or datasets? Both are available from web.. If you are looking for just pictures taken from space by astranauts, you can search them at http://photojournal.jpl.nasa.gov/targetFamily/Earth But if you are looking for data sets go to http://http://daac.gsfc.nasa.gov/MODIS/ you can download 250 meter-1km resolution depending upon the channel frequency. They are free but huge files almost 3mb per granules As for discussion on the topic, Nepal's topography poses huge challenge to build roads. Building roads in Nepal is almost like challenging the nature where human always looses. But since we don't have any other option but to build a road, we have to accept the fact that the landslides are inevitable. Just recently I went through Krishne bhir at the time of landslide, I found that they have built one stone terrace just next to the road as temporary solution which was not enough to hold landslide. My suggestion to the problem would be creating terraces as suggested by GP, but that alone will not be a long term solution. The area in between the terraces should be covered with some kind of strong nylon mesh which would keep soil intact for long enough time to grow vegetation Building a tunnel would be a good idea but can we afford it ?? If similar situation arises somewhere else, since there are many places with topography similar to Krishne Bhir can we build tunnel or some expensive alternative in each site?? |
| RBaral | Posted
on 18-Aug-03 08:15 AM
The solution would be to dig a trench to divert the river, and remove the meandering section. I don't know what the elevation defferences are, but it might work with pacifiers to reduce the current resulted by shortening the river stretch. A trench, however longer, could be cost efficient compated to two bridges. This way, the landslide prone areas (which GP has very cleary shown in his graphics) would be avoided. This solution will result in: 1. Shortening of road length (less wearing of tires, long auto life-- low cost of travel) 2. Long lasting solution to Bhir ko Samasya (regularity of road service..) 3. Very flat horizontal curves -- extended sight distance -- hence safety 4. Introduction of two verticle curves -- may imporve highway aesthetics, if designed and constructed wisely. I don't have photo editing tool (Re PHOTOSHOP) handy at this time therefore I couldn't show my proposal visually. As an immediate soultion, terracing and slpoe stabilizing (as suggested by Dr.GP) seems to be the best solution. Namaste, Rishi |
| GP | Posted
on 18-Aug-03 04:07 PM
Rishi and others thanks for your inputs. There seems to be a large deep seated landslide occured 100 or several 100 years ago. I am not sure whether its active or not. So, tunneling can not be an easy solution from maintenance perspective: When you talk tunnel you should think of following things: 1. ventilation. 2. light: continuous supply of electricity. 3. accident management. 4. periodic check: professional level: not at overseer level. Final comment: every civil engineering structure is a full scaled model test/ experiment. IF works its OK if does not work consider it an experiment, only thing you should note is that if it fails it should be lesson to next design, and if you just forget how and why it failed, its waste of public money, and is not an experiment. Well, when you design a structure design it atleast last your lifetime, this is what designers say..... a real concept .... so that you won't be prosecuted in courts for liability. At this moment, I will not recommend any tunnel in Nepal, except subway in Kathmandu Valley. Even in Kathmandu valley, subsidence that will be seen in next few decades will not let subway remain intact because of overstressing. So, tunneling can be good solution once we construct enough road network and tunneling starts when construction biz ceases e.g. in Japan, then, to engage construction industry govt. starts designing tunnels to straighten the roads. At this moment, resource poor country can not afford tunnels just to avoid small small landslides liike Krishnabhir. Krishna Bhir l.s. is not very big landslide, but, its govt. 's willingness to solve it integrating professional ideas. They should consult professionals, not just confine themselves .............. and why don't they have a conference on "Krishna Bhir " itself? GP |
| Manchhe | Posted
on 18-Aug-03 11:43 PM
Dear Arnico ji, RE : Krishna Bhir's feasibility...see drawing RE : Satellite picture... There is no satellite pictures for a micro study of the site so far. RE : GLOF... since the Trishuli river goes through rocky mountains, there is no threat of GLOF in Prithvi Highway. also please be noted that the Bhote Koshi does not merge into Trishuli. It goes to eastern Nepal. So no aditional threat to Prithivi Highway. RE BANEPA SINDHULI HIGHWAY : I agree your point... two years back, after driving on that highway, I talked with the donor (Jananese Embassador) regarding narrowness of the road. He just said 'Its a grant !'. which meant- Magne Lai Tato Bhat ! The Embassador is right to some extent. all the best.................... 
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| Manchhe | Posted
on 19-Aug-03 12:05 AM
GP ji, Your points on Tunnel 1. ventilation. 2. light: continuous supply of electricity. 3. accident management. 4. periodic check: professional level: not at overseer level. Answers 1. Lenght is approximately 100 metres (very shorter than Holland tunnel) 2. Vehicle's light is enough for 100 metres. But reflector is a must on walls and surface. 3. I think, in Nepal, tunnel is much safer than open high way as far as reckless driving (plunge into the river) is concerned. 4. Here, money matters !... however, periodic check is cheaper than current expenses on cleaning the debris (muds) throughout the year. thanks.. |
| paad ka | Posted
on 19-Aug-03 02:07 AM
Oye Gyanendra Poudel.....kay bhanchas sano purdkay....Japan ma bhasai ra computer ma maathcheenchas....Sala, aila Nepal ma cha.....Russia, owni hoina....Oye, moteh talu quelay sukyo.....kapal pani chaina....onara demo tabero....mero chak sniff ghar...namaste, sala 
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| allare | Posted
on 19-Aug-03 02:40 AM
Why do not people think of using alternative route rather than maintaing tunnel and blah blah in Krishna bhir ? Just divert the road little bit and let Krishnabhir flow in its own natural way. |
| Golkhadi | Posted
on 19-Aug-03 03:11 AM
Building a tunnel in such a remote part of nepal is pretty risky for eg crime,accidents and regular money should be spend on such tunnel. so i believe the tunnel idea is a bad idea. Why not build a bridge this side of the river as we see lotsa houses comparing to the otherside, these part will benefit form it as well and we forget about the landside forever. We build two major bridges and a small one. I am not clear of the map this side..but i think it will be money well spend for the benefit of the local community. 
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| Dilasha | Posted
on 19-Aug-03 10:34 AM
What a devastating picture! I wonder how the people who travel through that road and the ones who live in the vicinity must be going through. Hope the government finds the solution for this heart wrenching problem soon so it can be implemented as quickly as possible. GP ji, thank you very much for sharing this info with us and to the rest of the Sajhaites who shared their thoughts, thanks to you all as well. I too am not an expert on the field, but looking at the picture, I think building a "bridge" sounds feasible. Also, do they have a system of paying "toll" or what they call it, i'm not sure-like they do here overseas? i think funds raised through that system could help the government especially in covering the expenses in the long run. Again, I don't know much but would love to know more on this matter. I'ill also talk to my uncle and a friend who are both engineers and seek their opinion and try to share it with you later. And Paadka ji, shame on you to lash out on someone dedicated to such an important cause, someone who's taking the initiative to generate awareness as well as resolution. I would appreciate if you could refrain from such foul language. |
| GP | Posted
on 19-Aug-03 02:54 PM
tunneling can be solution, but, geologic histroy and deep seated movements if any should be prime reason to decide whether it lasts long. lets see a possible deep seated failure in the past (this is just my guess looking at the outer crop of the whole slope): 
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| czar | Posted
on 19-Aug-03 03:09 PM
Some years ago I was riding a night bus back from Pokhara. It was a rainy night, just a few weeks before Dashain. It was just before midnight that the bus lurched to a stop and, like other passengers, I stepped out to stretch my legs. There was alread a line of buses stopped ahead of our bus and, speaking to a few of them, I was informed that was a landslide at krishnabhir earlier in the evening due to the incessant rain. It was obvious nothing was going to happen till the dept. of roads bulldozer to turn up to clear the obstructions on the road. There was no village nearby, so passengers then faced a long soggy and hungry wait through the night. It was near dawn when the long awaited dozer finally arrived and went to work. At one point, I recollect seeing the dozer being pushed sideways towards the river by the flow of mud and rocks, but the driver kept his nerve and ploughed his way through it to safety. In the misty grey of the dawn, he drove that machine repeatedly into the dangerous slide till he cleared enough of a stable passage for vehicles to travel through one at a time. Now GP here is making loads of sense, so, as the delectable Dilasha says, the paad ka's of this world are well advised to lay of the obscenity and leave well enough alone. If perhaps you have a low cost and effective solution to the problem, by all means, lets hear it. If not, observe some civility and do please allow us to enjoy this educational discussion. |
| GP | Posted
on 19-Aug-03 03:13 PM
Maanche, I wish that I know you very well. hahahaah..... (because you referred meeting with Japanese Ambassador). Yes, the banepa-sindhuli road is exactly 75cm narrower than standard two lane road. Thus, the drivers of wider vehicles will not prefer to move along this road as the traffic gets congested, because they will be spending more time and they need more stops --ghachak ghachak-- to reach destination as compared to Narayanghat route. It will be mere a supplementary route to Prithvi + narayanghat route, and will be mainly used when the Prithvi highway will be closed due to krishna bhir like problems. As drivers know very well that stopping a vehicle will not only be loss of time, but, also consumption of fuel. Thus, in a country where gasoline is expensive, the drivers will be very sensitive to this issue. Japanese will need to offer widening of road just a couple of years after the innaguration of it. Anyway, landslide will not be major problem in Banepa Sindhuli raod, but, the section (about 1 km) near Nepal thok was already washed away by unpredicatable river flow and I can realize the vulnurability of the road. GP 
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| GP | Posted
on 19-Aug-03 03:31 PM
Golhadi, Dilasha and others your bridges are good in concept, but, selection of site is not so straight. Nepali rivers, e.g. 1993 rain created flash flood, and mud-boulders flows washed away the bridges near malekhu. Similarly, the river section should provide enough clearance for extreme cases. Rivers (based on my study) have four sections: 1. in mountains: where they initiate: smaller in size 2. near valleys: carry a lot of boulder. (near krishna bhir): high speed with a lot of suspended particles. 3. near narayanghat like stage. 4. near ocean mouth: in bangladesh: no speed, thus very bad indeed: all suspended load will be left behind. rivlets and rivers in stage 1 and 2 will be dangerous because of unpredictable rain in upstream. So, bridge construction needs record of rain fall history and its another problem in Nepal. Its really challenging job. Move up the hill: landslide is problem, move closer to flat / valley terrain, flash flood is problem............. Money is of course another major problem. Lets not forget that nothing is impossible in probabilistic concept, thus, failure is part of engineering works. Public should be told this that failure is not always avoidable, but, only frequency of failure can be reduced: with appropriate use of knowledge and money. GP |
| gunda | Posted
on 19-Aug-03 04:37 PM
I think its better to have slanted terraces or retention wall than horizantal terraces to deflect the pressure and erosion from the center. You have to build the terraces top to bottom which wil be very expensive as well. I think lot depends on compotion of the the hill. 
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| GP | Posted
on 19-Aug-03 06:02 PM
Gunda, I went to several dozens of technical visit and site visits to see the slopes and do investigations including the slope retaining / stabilization structures in last 12 years, I never come to see the structure you proposed. Wow, if I have money I would apply for Patent on the idea with your ideas. GP |
| Golkhadi | Posted
on 20-Aug-03 02:50 AM
I was only suggesting my bridge idea for the benefit of everyone including the residents living in this side of the river as there were few many houses than the other side of the river. I am an engineering student but certainly not a civil, my bridges could be at the wrong places but there should be some more possible places where the bridges could be built. I dont know about teraces, as its ''temporary" it could be only a temporary idea. And also i will like to remind GP as he said earlier that there are other possible places where we could have more landslides in the future..say with ine 2 years...so are planing to "slope Terrace"all the possible areas of landslides????? it could be few kms. the only possible way i see is find a better place to build a bridge this side of the village..at least they will have a better life too..rather flowing money in the river everyyear. |
| gunda | Posted
on 20-Aug-03 09:38 AM
I am surprised that GB never heard this idea before. I am not sure if we can make money from patenting this idea, but if we can make money from it , you can count on me. Just to let you know, I am not an engineer and I am not for the name, but for money yes. I have seen retention wall being over run by land slide so this idea just came to me, hey why dont we design it so that pairo could be diverted so it would not run over the retention walls. In staircases horizontal walls, if the top one falls, it will be blocked by the one below, if that falls it will just collect more weights and create pressure to the bottom one and finally bottom gives out. With my slanted wall, it will deflect the pairo, if there is slide on the top it will be deflected to the side and pressure will be reduced. Rather than sharp rectangular walls, you have slanted walls, its Feng Shuie way of doing things, creating harmony with nature. Having seen better pictures of other side of the Krishnay Bhir, I am all for taking the road to other side so that the inhabitants of that area are not isolated, so that they too can benefit from the road. I would keep Krishnay Bhir road as an alternative road since its already built. |
| thaag | Posted
on 21-Aug-03 11:19 AM
Modis satellite (Ch1) image - May 5, 2003. can any body post lat lon for krishna Bhir?? I might find detailed satellite image 
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| Gunaraj | Posted
on 21-Aug-03 12:29 PM
Let's try: 
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| thaag | Posted
on 21-Aug-03 03:23 PM
Here is the landsat image 30m resolution from Mar 27 2003, since I don't have exact lat lon, I don't know the circle I made is correct, you can guess and point out. full resolution image is located at http://www.sajha.com/uploads/Krishebhir_landsat_mar27_2000.jpg The image is made from landsat ch 3, 2, 1 (r, g, b). 
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| thaag | Posted
on 21-Aug-03 03:24 PM
correction, image is from 2000 not 2003 |
| thaag | Posted
on 21-Aug-03 03:35 PM
You might be able to locate your house in full res image ;) |
| NPB | Posted
on 23-Aug-03 05:17 AM
Krishnabheer just from a different angle As GP has already pointed out, without much investigation data it may not be very appropriate to talk about mass movement in the form of deep-seated gravitational creep, but as illustrated in the figure above, it is the reality. Possible mass of collapse in the long past has already been indicated by GP, so the active mass movement has caused heavy fractures in the bedrock near the ground. It resulted in debris fall during the first event of failure, and ever since the surface layer of 2-5m (approximate) has been moving in the form of debris slide under the influence of rainwater percolation and development of porewater pressure. Some of the problems in mitigation: 1. No proper analysis and investigation have yet been carried out 2. Let it fall, we will clear approach of coping it 3. Learn no lessons from previous events 4. Try to retain only the debris mass on the surface (approx. 2-5m) 5. Poor surface as well as subsurface drainage conditions 6. Work mostly during active period of movements (i.e. monsoon) What may be low-cost solutions? 1. Without trying much to retain the mass, reduce somehow the effect of rainwater. It may include a network of drainage borings and drainage ditches on the surface all over the site (might result in high cost but most effective among what has been practiced there until today). 2. Terraced slope as suggested by GP, but only after proper stability analysis and application of drainage network. Changing the road alignment passing over three new bridges is definitely a better alternate but it is going to be many times costlier than trying to stabilize Krishnabheer. To roughly estimate, we need about one billion (Rs.) to change the alignment, while a cost-effective stabilization after proper investigation may hardly require 3-4 hundred millions (not quite sure though!). On the other hand, if we go for a tunnel, which is yet to be practiced in the roads of Nepal, the cost is definitely going to be multifold. In addition, aligning a tunnel through an active landslide site will require landslide stabilization work. Otherwise, the tunnel can be aligned through non-moving part of the rock mass (as shown in figure above), which will again raise the cost. The Department of Roads might have already spent tens of millions of rupees in its stabilizing efforts, but what it does is something like shown in a picture above. Had all this amount been utilized in an engineering way, things would have been different. What needs to be done? 1. Properly investigate the landslide properties 2. Understand the real mechanism of movement 3. Carry out stability analysis and decide what the cost-effective control measures are 4. Speed up the work during dry periods and let less water percolate the slope debris 5. Do not expect an aid for stabilizing a landslide of medium size (may be very large in Nepal) 6. Stop other unnecessary projects (like??) and use the state fund to properly maintain the roads; change the road maintenance policy Thank you. (Note: the views expressed above are solely mine. Reading different views on Krishnabheer, I couldnt stop myself because I was recently in Nepal and had an in-surface observation of the landslide site. I would like to call myself a geotechnical engineer, so if anyone with the same or similar profession finds technically inappropriate suggestions, please discuss. Its an invitation, not a challenge.) 
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