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By Dr. Mahavir Bidasaria Er . Anupam Bidasaria Ferro Concrete Const. (India) Pvt. Ltd.,

RESTORATION AND REHABILITATION OF OLD PAGARA. (A Case Study) & RECENT ADVANCE DEVELOPMENT IN DAM REHABILITATION & RESTORATION - 3 DAMS -. By Dr. Mahavir Bidasaria Er . Anupam Bidasaria Ferro Concrete Const. (India) Pvt. Ltd.,. INTRODUCTION. PAGARA MASONRY DAM 100 Years Old.

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By Dr. Mahavir Bidasaria Er . Anupam Bidasaria Ferro Concrete Const. (India) Pvt. Ltd.,

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  1. RESTORATION AND REHABILITATION OF OLD PAGARA.(A Case Study)& RECENT ADVANCE DEVELOPMENT IN DAM REHABILITATION & RESTORATION - 3 DAMS - By Dr. MahavirBidasaria Er. AnupamBidasaria Ferro Concrete Const. (India) Pvt. Ltd.,

  2. INTRODUCTION PAGARA MASONRY DAM 100 Years Old  Salient features of Pagara Dam a. Location : It is situated near village Joura nearly 39 Km from Morena town in North M.P. Joura is a Famous place, where not only this dam is situated but it is the place of famous dacoit MAN SINGH who had lived at this place for more than 30 years. b. It is a composite dam built on Asan River. c. It consists of 244 m long masonry non overflow section, 73 m long masonry waste weir, 1439 m long earthen dam on left flank. The Max. height of this dam is 27 m.

  3. 1.0. CAUSES OF DISTRESS IDENTIFIED I.E. BEFORE REHABILITATION (YEAR 1994). Causes of distress were Identified based on the Investigations carried out by Geological Survey of India and CSMRS, and few conclusions were drawn. 1.1.Existence of geological fault zone at the junction of masonry and earth dam, which was not treated at the time of construction. 1.2. The masonry dam was resting on sand stone formation which had open joints. These joints had not been treated and there existed high permeability in the upper layer of foundation rock. 1.3. Distress due to ageing i.e. cracking erosion of mortar due to weathering action 1.4. On D/s face, lime mortar from joints had washed out & voids have been created & body of Dam become porous.

  4. 2.0 Remedial Measures were suggested in two parts Part - 1. Steps • To prepare u/s face by cleaning with help of air and water jet. • To Drill holes for anchor fixing on masonry face in Grid of 1 m. • To fix 20 mm anchor bolts in drilled holes. • Fix hard drawn wire mesh of 100 x 100 mm. on Anchors and tighten the mesh with washer of steel plates and nuts on the anchors. • Apply 50 mm thick Gunite on the surface with mortar of 1:3 proportion cement to sand. A. To gunite the entire up stream face of dam alongwithwire mesh reinforcement. It was recommended that the reservoir be emptied and dam face thoroughly cleaned and the guniteapplied in one continuous operation to ensure proper bonding.

  5. Part – 2. Grouting the body of the dam and upper layers of rock foundation to fill in all the voids created by leaching etc. with cement grout. The test grout pattern is proposed in two rows one meter apart and holes being spaced at 3 m. c/c in staggered manner. The first row of grout holes being one meter from the u/s. face of dam. After test section, different reaches of masonry dam was proposed to be grouted accordingly. It was important to drill holes atleast 3 to 6 m in base rock, to grout the upper permeable layer of sand stone foundation.

  6. 2.1.DRILLING OPERATION :- a) Drilling in two rows, holes at 3 m c/c were performed by using Rotary cum percussive drilling Rigs. b) Drilling in masonry has been performed in descending order method, where holes were drilled at 3 m c/c. in stages of 6 to 9 meters. The first stage so drilled is washed with jet of air and water till all the drill cutting comes out. 2.2. WATER TEST / PERMEABILITY TEST :- Water test (cyclic) were taken in every stage. Permeability of strata is measured in terms of Lugeon. Lugeon is a unit of water loss measured in litres, per meter, per minutes at a water pressure of 10 Kg./cm2

  7. 2.3. Grouting Operation. Grouting has been executed as per IS 6066 by starting with thin mix of 1:10 cement to water and thickening the same as the grouts intake increases and ending with 1:1 by weight. Typical arrangement of grouting plan set up

  8. 3.0. CONCLUSIONS AND RECOMMENDATION. 3.1. With the use of cement grout, a very badly leaking masonry dam, having voids and high porosity was completely made water tight and structurally sound. 3.2. It is essential to provide pointing on the u/s and d/s surface of dam before starting of grouting. 3.3. For grouting a badly leaking masonry dam, cement grout is sufficient. At few places wherever porosity is very high, colloidal grout of sand and cement can be used. 3.4. It is essential to provide inclined pressure release holes in the masonry portion from d/s. face of dam, to release the pore pressure because there is no foundation gallery. The holes must penetrate through body of the dam, and minimum 1 m into the foundation rock, at about 5m from the u/s toe of the dam. Spacing of hole be 15 m centre to centre.

  9. AFTER GUNITING & GROUTING TREATMENT BEFORE GUNITING & GROUTING TREATMENT (Full dam view from D/s)

  10. RECENT ADVANCEMENTS IN DAM REHABILITATIONS. Pagara dam was constructed about 100 years back and rehabilitation took place in 1995. Now a days many more advance technological changes are taking place. Recently three old dams (Up to 90 years old) are under rehabilitation in Karnataka State by FCCI. These are heavily leaking masonry and concrete dams:- 1) KrishnarajaSagaraDam on Cauvery River , Near Mysore in Karnataka. This world famous hydraulic structure, designed and constructed under the guidance and supervision of father of Indian Civil Engineering Sir Vishveshwaraiah. 2) Almatti Dam near Bijapur on River Krishna, in Karnataka. 3) Bhadra Dam near Shimoga on River Bhadra, in Karnataka.

  11. Methodology adopted, to stop this seepage is to carry out : 1) Upstream face pointing, using UV resistant high strength shrinkage compensating polymer modified cementitious mortar. 2) Drilling & Grouting from top of dam, using Cement with chemicals. 3) Grouting of upstream face by inserting pipe on upstream face for Horizontal grouting 4) Use of Hydrophobic Polyurethane grout to stop large seepages.

  12. KRISHNARAJA SAGARA DAM Main dam view

  13. Downstream face of K.R.S. Dam showing prominent leaking spots.

  14. Upstream face treatment being done by raking out old mortar and providing new pointing of UV resistance high strength Cementitious mortar. Cradle Cradle

  15. Drilling and Grouting works in progress from top of KRS Dam by Rotary drilling method and grouting with OPC 53 Grade cement alongwith non-shrink admixture.

  16. Panoramic view of dam

  17. Downstream face of Almatti Dam showing prominent leaking spots.

  18. Drilling and Grouting works in progress from top of AlmattiDam by Rotary drilling method and cement grouting with admixtures.

  19. Downstream face of Bhadra Dam showing prominent leaking spots. Panoramic view Main Bhadra Dam

  20. Drilling and Grouting works in progress from top of Bhadra Dam.

  21. Material and Chemical used in these Three Old Dams for Upstream Pointing and Grouting are abstracted as below. Name of Dam Pointing Material Body Grouting Material Steripure 100, Kelox R-101, Kelox R-404, Nicomix 100 with OPC 53 grade cement, Kelmer A-80, Nicocoat PC with cement Cement OPC53 + Cebex100 (Admixture non Shrink / super Plasticizer) KRS Dam Mysore Almatti Dam Bijapur Reebaklens, Nitobond EP (Hardner + Base), Rendroc HS Xtra, Nitocote SN-522 Cement OPC43 + Silica + Tam Seal Crystalline. Proportion 1:3:½ Cement OPC43 + Cebex100 (Admixture non Shrink / super Plasticizer) Bhadra Dam Shimoga Reebaklens, Nitobond EP (Hardner + Base), Rendroc HS Xtra, Nitocote SN-522 Treatment work ON ALL THESE DAMS ARE IN PROGRESS.

  22. THANK YOU

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