ADDN/ALTN TO STRUCTURAL ITEMS OF BLDG NO P-6 AND P-7 FAFA MD ACCN UNDER GE (EAST) DELHI CANTT-10

M&L for Preventive treatment against the danger of carbonation in exposed faces of RCC members :- (i) Cleaning existing surfaces of RCC members and making surface free of loose material, oil, grease etc. by vigorous wire brushing including light grit blasting where necessary as recommended by Engr-in-charge. (ii) Further, cleaning using biocide(as recommended by manufacturer) to ensure that surface is free of algae and fungus and no trace of paint (any type) left out. Sand blasting to be done to remove trace of paint. (iii) Cleaned surface to be allowed to dry. (iv) Spray a coat of primer (as recommended by manufacturer) over dry cleaned surface as required prior to final finish. Primer shall be diluted in proposition 2:1 with mineral turpentine. After application, primer shall be allowed to dry for 03 hours or as directed. (v) Apply a coat of neat Aliphatic Acrylic anti-carbonation (ACC) over the primed surface with air / spray gun at nominal rate of 3.5 ltrs per sqm as recommended by manufacturer. (vi) Apply a more coat of Aliphatic Acrylic anti-carbonation (ACC) after 5-6 hours as recommended by manufacturer complete all as specified and directed. (incl necessary scaffolding to execute the work upto G+3 storied buildings complete all as specified and as directed)

M&L for followings for preventive treatment to RCC members:- (i) Removing plaster & finishes all around the coloumns, slabs & beams (on all four sides cription of column to full height, three sidescription of beam to entire span & bottom of slab to area as directed) (ii) After cleaning gently removing cover concrete using pneumatic/electric chipper or any other approved tool in entire portion of structural member (removal of cover concrete shall be done to an extent when reinforcement is visible) (iii) Removal of cover concrete with under cutting of up to a depth of 20mm beyond reinforcement around full circumference & full length of bar where directed. (concrete shall be stripped to an extent concrete substrate is exposed) (iv) Cleaning exposed concrete substrate by using water jet. (v) Removing visible rust along the length of reinforcement using hand tools as approved. (The Engr-in-charge may order sand blasting if rust is approved) (vi) Any other work as directed by Engr-in-charge to present clean surface for determination of type of repair to be carried out complete all as specified and directed. (incl necessary scaffolding to execute the work upto G+3 storied buildings complete all as specified and as directed)

M&L for providing rust proof /anti corrosive treatment to reinforcement bars :- (i) cleaning of all exposed bars (new & old) alround (ii) Apply a single coat of Alkaline rust converting primer on alround bars new & old as recommended by the manufactuer (iii) Apply two coats of Epoxy phenolic anti corrosive protective coat on bars alround new & old as recommended by the manufactuer. Note : Anti corrosive treatment shall be continuous espcially in the regions where pitting, imperfections, etc were present on the surface of the steel bars. It is important that the rear portions of re bars (those towards the concrete substrate) should not be left without coating. (incl necessary scaffolding to execute the work upto G+3 storied buildings complete all as specified and as directed) (Note: Treated area of steel reinforcement bar shall only be considered)

M&L for providing PMM (Polymer modified cementitious mortar) :- (i) Dry sub strate surface and free of debris & dust (ii) Applying Epoxy bond coat on the sound substrate using approved spray machine & ensuring that no pin holes are visible.(In case pin holes are still visible after a coat, a second coat shall be applied to ensure absence of pin holes). (iii) Immediately after application of epoxy bond coat as above apply PMM (Polymer modified cementitious mortar) of 25 mm thickness. Note : Application of PMM shall be preferably be in coats of appx 10mm thickness each. PMM work shall be executed in fairely rapid successions so as entire work is completed with in 30 mins). PMM shall be pre packed ready to use. (iv) PMM surface to be moist cured for three days followed by air curing in temperature as recommended by manufactuer complete all as specified and directed. (iv) PMM surface to be moist cured for three days followed by air curing in temperature as recommended by manufactuer complete all as specified and directed. (incl necessary scaffolding to execute the work upto G+3 storied buildings complete all as specified and as directed)

M&L for treatement of cracks found in the core concrete :- (i) Opening of crack by making a ' V' notch/groove of size 12mm x 12mm over the entire length of the crack as identified by the Engr-in-charge. (ii) cleaning ' v' notch/groove of all dust/debris/loose material (iii) Drilling hole of 16mm dia and about 40mm deep along the length of crack @ (300 mm c/c or thickness of structural member whichever is less) Note : In case length of crack is found less than 300 mm then min 2 holes shall be drilled. (iv) Inserting 12 mm dia flexible PVC one way injection nipple in the hole drilled above and fixing the nipple with the help of fast setting epoxy putty. (v) seal the surface around the nipple and the area of crack between successive nipples polymer modified mortar to ensure that there is no leakage from any gap. (vi) Allow the polymer modified mortar to cure for 24 hours and ensure that firmly fixed in postion. (vii) cleaning nipple one by one commencin from the top to bottom in case of column and one by one in alternate direction incase of beam/slab using blow compressed air followed by water injection. An Ensuring that there is no obstruction in free flow of grouting materials complete all as specified and directed. (incl necessary scaffolding to execute the work upto G+3 storied buildings complete all as specified and as directed)

M&L for treatement of core concrete when found to be porous/honeycombed :- (i) Marking the area in marker as directed by the Engr-in-charge. (ii) Drilling holes of 16mm dia in an orthogonal grid on exposed cone of member @ 150 mm c/c both way, depth of the hole shall be about 60% of the element thickness. (iii) clean the drill hole using compressed air removing the dust/dirt. (iv) Inserting 12 mm dia flexible PVC one way injection nipple in the hole with the annular space around the nipple sealed with epoxy putty. It shall be ensured that the injected grount does not leak. (v) Allow the nipple to cure for 24 hours. (vi) Injecting " Resin with very low viscosity monomer by mixing resin and hardener in proportions recommended by manufacturer by using injection gun equipped with pressure gauge & valves for controlling of flow of compressed air & resin. Note : pressure shall be in the range of 2-3 kg/sqm and shall be done in nipples one by one as per order recommended by manufacturer. Mixing of resin and hardenere shall be mixed in small quantities so as it is consumed with in 30 minutes. Before use mixer shall be stirred thoroughly. (incl necessary scaffolding to execute the work upto G+3 storied buildings complete all as specified and as directed) (vii) Allow entire effected surface to cure for 24 hours. (viii) cutting out projected parts of the nipple & seal the hole in the nipple with epoxy putty as recommended by manufacturer. (ix) cleaning exposed surface of substrate off any dust /loose material after ageing of the grout as recommended by manufactuer.

Supply & fixing 12mm dia steel sheer connector in grid pattern in between old core and new concrete as wherever directed by Engr-in-charge and as specifed by manufactuer including drilling hole of depth of 100 mm and chemical anchoring with pure epoxy resin anchoring mortar (Master flow 935 of BASF or equivalent FOSROC/SIKA). (The cost of drilling hole & chemical anchoring with epoxy resin shall be deep inclueded in this item) complete all as specified and directed. (incl necessary scaffolding to execute the work upto G+3 storied buildings complete all as specified and as directed)

M&L for Providing & Pouring Micro concreting M-40 grade :- (i) Dry concrete substrate surface and free of debris & dust (ii) Applying Epoxy bond coat on the sound concrete substrate using approved spray machine & ensuring that no pin holes are visible. (In case pin holes are still visible after a coat, a second coat shall be applied to ensure absence of pin holes). (iii) Immediately after application of epoxy bond coat as above pour Micro concreting M40 grade, Make : MasterEmaco S46T of BASF or equivalent FOSROC/SIKA using approved mixing machines/ pumping under pressure via approved pneumatic pump at the locations to be repaired in RCC slab, beams & columns etc,. Adding of aggregates will be permitted only as per manufacturer’s recommendation without compromising the strength. The rate shall include cost of all materials (except re-bar) labour charges for mixing, pouring concrete, cost of tools, lead & lift of materials, transportation etc., to carry out the complete work complete all as specified and directed. Note : The cost of micro concrete M-40 grade & Epoxy bond coat is inclueded in this item. (incl necessary scaffolding to execute the work upto G+3 storied buildings complete all as specified and as directed)

M&L for Drilling & chemical anchoring of new rebars/stirrups :- (i) Drilling in to the sound RCC members for anchoring of rebars/stirrups as directed, the dia of hole to be match with dia of rebar & length of drilling as under :- 8 mm dia bar - drilling length 80 to 100 mm - 384 Nos Note : Anchoring of new re-bars of any dia as directed in to the sound RCC members as directed using pure epoxy resin anchoring mortar (Master flow 935 of BASF or equivalent FOSROC/SIKA) with appropriate diameter of drilling of holes as mentioned above for proper bonding into the concrete etc., complete. (The cost of drilling hole & chemical anchoring with epoxy resin is inclueded in this item) (incl necessary scaffolding to execute the work upto G+3 storied buildings complete all as specified and as directed)

M&L for Drilling & chemical anchoring of new rebars/stirrups :- (i) Drilling in to the sound RCC members for anchoring of rebars/stirrups as directed, the dia of hole to be match with dia of rebar & length of drilling as under :- 16 & 20 mm dia bar - drilling length 160 to 180 mm - 700 Nos Note : Anchoring of new re-bars of any dia as directed in to the sound RCC members as directed using pure epoxy resin anchoring mortar (Master flow 935 of BASF or equivalent FOSROC/SIKA) with appropriate diameter of drilling of holes as mentioned above for proper bonding into the concrete etc., complete. (The cost of drilling hole & chemical anchoring with epoxy resin is inclueded in this item) (incl necessary scaffolding to execute the work upto G+3 storied buildings complete all as specified and as directed)