Dissertations/Theses - Department of Water Resources Engineering
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Item Critical evaluation of design of deep tubewells in Thakurgaon area(Department of Water Resources Engineering, 1986-08) Sarfaraz Wahed, Md.; Abdul Hannan, Dr.For abstract please see full textItem Effect of size and unit weight of materials in bank protection(Department of Water Resources Engineering, 1975-01) Ain-un-Nishat; Abdul Hannan, Dr.A study to determine the suitability of a lighter material, such as 'burnt clay lump' which is can be made available localy, to replace stone in bank protection work was taken up. The effect of size and unit weight of materials in bank protection was studied in laboratory in a straight channel using cubical blocks made of sand-cement morter and brick. Saturated sand-cement bJ.ock had a specific gravity of 2.68 resembleming that of stone and brick blocks had a specific gravity of 2.18. Critical velocity at faiJ.ure of the blocks used as bank protective material was determined on four different side slopes. The volume of blocks was found to vary with the velocity at failure as the 6th and 7th power for sand-cement blocks and brick blocks respectively. The weight of blo.cks was found to vary with the velocity at failure as the 4.75th and 5.5th power for sand cement blocks and brick blocks respectively. It was observed that interlocking of the blocks and the waves in the channel are also major factors in the determination of proper size. of bank protective materials. It was also concluded that on a flatter side slope blocks of much less weight are required.Item Experimental investigation of the effect of location and projection of single groin in a bend(Department of Water Resources Engineering, 1983-08) Abu Obaida Ansari Khan, Md.; Abdul Hannan, Dr.For abstract please full textItem Study of selected BWDB small scale projects(Department of Water Resources Engineering, 1990-08) Matiur Rahman, Md.; Abdul Hannan, Dr.To get an immediate impact on the food-grain self-sufficiency, the Government of Bangladesh took initiative in implementing Small Scale Water development projects to get quick benefit at least cost. This strategy helped to develop some potential area for agriculture on a priority basis. It was also aimed to take the benefits of development works in a distributive way to the target group of popu1ation(Landless and Marginal farmers group). Following the concept, a large number of small scale projects have already been completed and many are sti 11 now being implemented by BWDB. Three such projects which are already in operation have been chosen for the present study to visualise the level of their performance. These are Mashajan-Lauhajong project, Polder 65/A- 3 project, Mondakini Khal irrigation project. The study reveals that Mondakini khal irrigation project is a successful one. It is being maintained as and when needed. It was evaluated well after its completion. The study reveals clearly its success in respect of different aspects of national development through increased agricultural production and also through socio-economic well-being. Mashajan-Lauhajong project is an incomplete one and Polder 65/A-3 project is in serious state of disrepair; but the result of this study shows their potentiality in obtaining the desired goal if rehabilitated properly. The study reveals the need for completing the excavat ion of the dra inage cana 1s upto the des ign requ irement in Mashajan- Lauhajong project and raising of embankment he ight by another meter with reconstruction of breached portions of embankment in Polder 65/A-3 project for their proper functioning. It is found from the present study that Mondakini Khal Irrigation Project, which is a completed and reasonably maintained BWDB Small Scale Project, has helped increase agricultural production to achieve selfsufficiency in food-grain. It is felt that rehabilitation work need to be carried out for projects having serious complaints of incompleteness and disrepair like Mashajan-Lauhajong Project and Polder 65/A-3 Project. It is also felt that comp 1eted projects should be supported with adequate ma intenance fund and fostered by a local project maintenance committee formed of the members from the beneficiaries and backed by Bangladesh Water Development Board. This aspect should be given due importance in all projects. An implemented project should also be backed by farm support measures to attain increased agricultural productivity. This also deserves due attention for getting optimum benefit from any such project.Item Study on changes in river-section characteristics of Brahmaputra-Jamuna station(Department of Water Resources Engineering, 1989-11) Halder, Swapan Kumar; Abdul Hannan, Dr.For abstract please see full textItem Study on morphological behaviour of Brahmaputra - Jamuna river(Department of Water Resources Engineering, 1995-10) Mukherjee, Provati; Abdul Hannan, Dr.For abstract please see full textItem Study on the performance of deep tubewell and aquifer characteristics inside Dhaka city(Department of Water Resources Engineering, 1984-09) Md.Serajuddin; Abdul Hannan, Dr.For abstract please see full textItem Study on the well-loss of BADC deep tubewell(Department of Water Resources Engineering, 1994-04) Zahidul Islam; Abdul Hannan, Dr.For abstract please see full textItem Subsurface aeration of ground water for the development of low cost iron removal device(Department of Water Resources Engineering, 1999-10) Ashraf Mahmud, Sayed; Abdul Hannan, Dr.The relative purity and abundance of ground water increase it's usage. In some places the iron content in ground water is so high that this metal mU:5tbe :removed before water can be used for drinking or industrial purposes. Iron occurs in two states of oxidation in nature- ~e ferrous (divalent)and ferric (trivalent)forms. The subsurface aeration technology developed oxidizes the ferrous ion, which is soluble in water, to the ferric ion, which is insoluble before it comes to the treatment unit for further action and separation. This method achieves a high degree of oxidation in the ground water during it's lifting. An airlift pump is employed in the tube well instead of turbine or submersible pumps. Air is forced down into the well under water and an air-water mixture is build up which has a lower density and thus come out of the well. The mixture obviously becomes enriched with oxygen. The air compressor used in an air lift pump selVes at least four purposes- lifting of water, aeration of water; regeneration of encrusted tube well and frequent cleaning of iron sludge from the interstices of the course media flocculator in the flocculation chamber. The encrustation of tube well strainer develops higher draw down, causes failure of shallow tube well and hand pump tube well. The regeneration is necessary for the encrusted tube wells for ensuring required discharge resulting energy saving- thus the operating cost. On the other hand regeneration of flocculators increases the efficiency of the coarse media bed. The unit cost of production of treated water in the subsurface aeration technology has been found to be Tk.1.20/ m3 while those of DPHE urban water supply is Tk. 1.81/ m3, calculated assuming lSOJ'6 discount factor, in areas where ground water has higher Iron content (Fe>5ppm). The dose of sodium Hexa-metaphosphare for the regeneration iron encrusted tube well has been calculated and has been found to be suitable for the use in regeneration work supported by air surging from the air compressor. The process of precipitation of iron in the aquifer has only a slight affect on aquifer permeability. The clogging of aquifer surrounding the well will not occur for a period many times longer than the life span of a typical well.