Tower erection - construction sequenceTowers to be erected equentially, starting with the right hand side to enable procedure to be adjusted and perfected for the more difficult left hand side1. Check as built dimensions of tower foundation, including overall foundation and pocket dimensions for both tower and A-frame2. Check dimensions and construction quality of main towers, bracing, gusset plates, and number of bolts. Make sure we have the correct number of bolts/braces etc!3. 4. Erect one-storey scaffold tower for assembling towers, Assemble flat on ground on RHS, may not be necessary on LHS?5. Place tower posts with base end adjacent to tower pocket and top end resting on scaffold tower6. Clean out tower pocket, A-frame pocket and top of tower column as best as possible. If raining, cover top of tower column with tarpaulin7. Fix bracing between posts and check posts are parallel is this by eye? Bolts to be hand tightened?8. In parallel to 5, assemble and install A-frame structure into place. Is this just embedded into pedestal? Tie down with guy ropes as well for added stability?9. Fix in timber beam and legs and attach to top of tower with guy ropes, here or later? Training to tie knots?10. Attach 4 guy ropes to top of tower (temporarily attach to posts to avoid trip hazards)11. Prepare plumb bob and fix to outward face of tower near top. Length of plumb bob such that bottom is close to top of pedestal. Proper plumb bob used? Or just rock on the end of a piece of string?12. Mark locations of embedment depth/pedestal height on posts (700mm from bottom, make sure this is visible when slotted in place!13. Fix 2# cables from top of each post to each anchor block to prevent over-rotating during lift. 1 cable per post? Attach to CHS in transition block or loop bar? Id recommend CHS to avoid potential local bending of bar14. Prepare hoisting cablea. Tie hoisting cable to the top of each postb. Thread hoisting cable through A-frame structurec. Secure winch or cable pulling device to transition block rebar on opposite side of riverd. Prepare location for pulling cable15. Place tyre at back of pocket to and coat with oil in preparation for erection of steel tower. This is to prevent any scraping damage to the pedestal. 16. Set a rope (sacrificial) over the bottom ends of the steel tower columns (this may need to be secured to prevent slipping off). This rope should be long enough to allow numerous pullers, at 10 m distance, on both lateral sides of the tower (no one should be positioned in the rotation direction of the tower). The purpose of this rope is to help control the movement of the base of the tower.17. Pull cables evenly and steadily to raise tower; initially test mechanism for locking winch during lift to allow for hold points18. Towers slides into pedestal pockets. Ensure tower sinks to correct depth (using marks made as a guideline on tower to confirm. If stuck, use jacking plates to lift and adjust.19. Fix guy ropes to ground and anchor blocks to provide temporary lateral stability. So what ropes are being used as support during lift itself?20. Adjust verticality (and pre-inclination) of posts using timber wedges and plumb bob21. Fill tower pockets with concrete (maximum 10mm aggregate size)22. After 2-3 hours remove hoisting cable from the top. How many hoisting cables will we have? Assuming 2, we will need to remove these to erect tower on other side prior to assembling scaffolding to get saddle joint in place. How to remove hoisting cable? Using a ladder?23. Assemble scaffolding (see scaffolding overview document).24. Fill top portion of tower with concrete (maximum 10mm aggregate size), stopping 100mm short of top of tower. As best as possible, compact the concrete (in steps) using a ~2m section piece of rebar. 25. Fill top of tower with 100mm fine grout, overfilling section26. Plunge saddle into grout and adjust as required27. Once concrete has cured sufficiently (24 hours after finishing concrete works) remove temporary ties and timber wedges, fill remaining portion with concrete