CIRCULAR WALLS - CLIMBING FORMWORK

Salient features of the Formwork used for the Construction of CIRCULAR WALLS: Structure details: Total height of tower is 50m. Thickness of wall 400mm Total number of pour is 14 Pouring height per lift 3.60m Formwork details: 1. L&T Wall formwork with Travelling climbing system (CB 150F) used for circular walls. 2. L&T Flex / HDT used for inner slab & beams. 3. L&T Lift shaft system used for Inner platform 4. Approx. size of wall panel is 2.0m x 3.60m 5. Outer shutter panels are supported on a pair of brackets.

6. Each pair of shutter panel with brackets having in-built safety such as necessar y handrails for concreting & shutter platforms. 7. Tower cranes used for lifting of shutters from one pour to another. Method statement of L&T formwork system: 1. Casting of Starter with timber sides to suit wall dimensions. Assembly of formwork: (For 1st Pour) 1. Placing of Shutter panel, check the line and level, then placing other shutter p anels continuously along the one side of the wall. 2. Inserting the Tierods upto other side wall surface covered by PVC pipe at the re quired locations (ie. As per scheme drawing & design calculations) 3. Placing of other side Shutter panel and check the edges with plumb, then placing other shutter panels continuously. 4. Extending the Tie rods and fixing with Anchor plate & wingnut. 5. Placing Alignment props / Supporting bracket with Head adapter assembly & Foot a dapter assembly. 6. Joining the shutter panels together by using Std. Splice plate (ie. for standard panels; For panels of non standard size, Adj. Waling Extn. with Beam clamp arrangement) with Connectin g pins. 7. Fixing of Timber spacers (for wall thickness) at H-beam locations on the top bet ween the shutter panels 8. Plumbing of shutters by using alignment struts / plumb bobs. 9. Checking the straight line of the both shutters with the help of line thread. 10. Checking the wall thickness at the top. 11. Universal inside corners to be fixed according to the requirements of inside wal l corners. 12. Stop anchors, Anchor cones covered with PVC sleeves at 500 mm from the top of co ncrete level to be fixed for subsequent lift done for climbing system. (max distance should be 2 .40 m c/c) 13. Place the suitable pocket made of plywood for shaft main beam / climbing pawl. 14. Necessary dowels/ Bar couplers to be placed & bent suitably with stopper for the slab if any depending upon the construction joints.

Removal of formwork: First removal of Tie rods, Alignment struts, accessories Removal of shutters (each separately) with the help of crane Cleaning and shifting of shutter panels (with alignment props / supporting brack ets) to next lift. Assembly of formwork: (For Typical Pours) using Climbing CB150F 1. After dismantling the shutters, remove anchor cone using DK spanner and fix clim bing cone. 2. Climbing bracket 150F 2 nos (to suit stop anchor location which is already left in conc.) should be made as a set by bracing with NB 40 pipes and couplers. 3. Fix working platforms with 6 X 3 as supporting timber and 2 thick planks. 4. Fix the Vertical waling (roler below the waler should sit over the bracket and s cissor action spindle (in collapsed condition) with the help of Locking pins. 5. Brace the vertical walers properly with horizontal and Diagonal by NB 40 pipes & couplers. 6. Fix the vertical waler with Climbing bracket tightly with wedges to prevent move ment. 7. Fix Handraill post on each bracket and hand railing at 2 levels should be done w ith NB 40 pipes & couplers.

8. 1 thick timber planks to be fixed as toe board in the hole provided in the climbi ng bracket. 9. Lift the entire assembly of climbing bracket 150F (by putting the sling on the t op of the vertical walers) with the help of crane and place over the climbing cone correctly. Lock the clim bing bracket with the locking pin to arrest upward movement of bracket from climbing cone head. 10. Follow the procedures described in the assembly of wall formwork, however the al ignment props to be removed. 11. Vertical walers should be connected with horizontal walers using waling to brack et holders. 12. Top leveling of shutters and adjustment of verticality done by adjusting the scr ews at the bottom of the vertical walers. Aligning of shutters should be done with Scissor action spindle s. 13. Check the verticality of the shutter using plumb bob. 14. Make lift shaft platform at ground with climbing pawl for inner platform. 15. Shift the platform with help of crane & place it where the pockets already provi ded. Dismantling: Roll back the shutters from concrete face. Put the crane sling in the hook provided in the Vertical waler. Take out the locking pin in the climbing bracket, so that the climbing bracket c an be free for lifting. Lift the entire assembly (including shutter panel and climbing bracket 150F asse mbly) and place it in next position. Remove Inner shutter panels & shift by crane to available place temporarily. (lo w level slab if any) Lift the Inner shaft platform to next higher level. Folded Dowel bars will be taken out by chipping & Bent to required position. Structural consultants should approve the slab casting & free standing height of walls.