Method statement for raw material silo. Project description1。0 Raw material silo：RCC silo, outside diameter is 23.472m。A cone starts at 8。693。 Ring foundation is adopted。 Concrete structure for the top。 。 References1。0 Drawings of raw meal homogenizing silo kiln feeding system2.0 The construction organization and design 3.0 The relative construction codes and regulations。 Main construction method 1。0 Preparations1。1 Equipment: Mobilization and commissioning of tower crane， sliding devices, welder, etc, so as to ensure the slip form works in the normal way。 1.2 Materials: Work out the plan of steel and carry out the fabrication work， prepare the plan of concrete and other materials。1.3 Job site: Smooth and straight so as to ensure the convenience of material transportation.1。4 Adequate manpowers。2。0 Silo wall slip form construction2.1Slip form constructiona. ConcreteThe concrete adopted for this job will be ready mixed concrete。 The following data shall be noted in the plan sheet: pouring and vibrating time， pouring section， strength requirement， slumps and the quantity (cubic meters） intended to be poured and planned time of pouring. When slipform starts， the concrete shall be continuous, and the masons follows to vibarte。 The concrete will be put into formworks and vibrated at the same time from both directions， so as to avoid the occurrence of slots or cracks caused by the already hardened concrete when only work to one direction. The proper slump requirement for slipform is 90140mm。 Concrete transportation: the concrete in the selffabricated tipcart will be transported by the headframe to the sliding platform， and supplied to place of pouring by the tipcart.Vertical transportation： After calculation, the capacity of the tower crane meets the actual transportation demand。 At the same time vertical transportation of the concrete should meet the demand for different section, Therefore， three headframe, which could goes up with the platform, is needed for silo wall sliding up, and selffabricated tipcart, actually the capacity of the lorry is 0。18 cubic meters。 Concrete pouring: when the silo wall is sliding up， put the concrete from the tipcart onto the platform between two slip form supports， masons shovel all the concrete on the platform into the formwork， masons following to vibrate the concrete. The concrete shall be continuously, and put into formworks and vibrated at the same time to both directions， so as to avoid the occurrence of slots or cracks caused by the already hardened concrete when only work in one direction.After put the concrete into the formwork， vibrate it in time with poker vibrator。 The working principle is “quick insert and slowly pull out, “one vibrator after another”， “vibrating in parallel。 For each point, the vibrating time is 20s30s， the vibration could not be stopped only when the concrete surface does not go down obviously， and there is no air bubble comes out， and thick liquid occurs on the concrete surface. When vibrating the upper layer， the insert to the lower layer could not more than 5cm and connection joints between these two layers shall be eliminated. No vibration and over vibration is forbidden。When concrete is delivered, slump should be checked。 The proper slump for slip form construction is 90140mm.Records must be taken and kept for the strength test, and mark out the pouring section and strength etc. The concrete shall be crushed at 7 and 28 days。 When results are satisfactory, the documents shall be kept in the archives。 As for the disqualified cubes， the reasons have to be found out and actions for that batch have to be taken。b。 ReinforcementThe vertical rebars lapping shall staggered at 1/4， and the overlapped area of ring horizontal rebars shall be no less than 50d. when the overlapping joints staggered distance is longer than 1000, then one rebar could be overlapped in the same area every four pieces. The rebars above the door and of the silo wall shall be bond when sliding up， the binding works shall be done with the concrete grouting one after the other.The concrete cover and position of the rebars are ensured to be correct by the clips installed in the horizontal beam of the slip form supports。c。 slidingupPreliminary slidingup: when begin with silo wall grouting, the concrete shall be grouted in 3 layers into the formwork of 1200mm on both directions。 Try to slide up the wall after 4 or 5 hours with 2 to 4 courses。 Test the concrete out of the formwork with hand， when there is only a slight fingerprint and the concrete does not stick to the hand, then the normal sliding up procedure could be carried out after a short break.After completion of the soleplate construction, the above-mentioned method shall be taken for the grouting of upper silo wall. Attention：When start constructing silo wall above the soleplate, please pay attention to see whether the concrete strength of the sole