Open Source Concrete Work

From Open Source Ecology
Jump to: navigation, search

Notes

  • Get yourself a power trowel - [1]
  • Polymesh F is an extra $5/yard for concrete work - [2]
  • Fiber still requires rebar [3]
  • Use Steel Fiber Concrete for strength - not available in many places.

Workshop Foundation

  • 3000 sf build of prototyping area for the Seed Eco-Homes, for building a second workshop space, with various prototyping experiments from material production to large CNC machines, 2021. Large truss structure at Universal Prototyping Structure

Open Source Power Trowel

  • Combo blade - that is what they have at Rentall
  • This is their finish blade.
  • In video below, they show float and trowel blades as separate?

Notes On Technique

  • Source 1 - [4]
  • Temporary screed posts explained here for larger slabs poured in sections:

  • 14 foot sections are laid down, so it's convenient for a scree board. Work in 14 foot strips. Bull float follows right after screeding. But how do they keep the screed board level? This guy also sells a course on how to start a concrete business doing work like this.

  • Extender truck or chute extender; conveyor is another form of extender; pump truck otherwise for going uphill. Conveyor truck vs pump truck.. Here is a wet setting of edge rebar reinforcement:

Note also the height level rebar stuck in and cleared at 1:40 - to set screed level.

  • Concrete stakes - metal with holes:

These guys above use screen boards put in at the right height - note Mike Day in last video doesn't do that - they set the level with the height set at 1:40 in the last video

  • More slabs with screed board levels put in, as opposed to the level stake. Mike Day is much more elegant, not requiring the section boards. [5]. It looks like the skilled guys do the rebar stakes for level, the less skilled crews do the scree height boards? The skilled guys appear to stand on the outside of the concrete at ends of screed board, the others stand in the middle of concrete. Right - the effficient guys seem to use stakes in the middle of the field to mark the level of the screed boards - not using set screet boards with concrete stakes. Saves loads of labor in setting up the screen boards, and saves the screed board removal effort. See [6]. Mike Day takes 1 hour to pour 45 yards [7].
  • Wet pad - after you get the level - you screed an area that serves as a guide for where the level of the concrete has to be. You can use a laser or a stake in the field. You do a little troweled round area, and then a longer line that you can follow - see this time [8].
  • Lower shelf concept - lowering on edge so water doesn't get in. [9]
  • Power trowel - combo blades - same blade for float and trowel. Video also shows a pan blade for troweling - flat disk - [10]
  • More about power trowels [11]. How do you start one? Here - [12] - and the pattern you follow over the slab. [13]

Understanding Concrete Timing

In good weather - power trowel is about 2 hours after pour is finished.

  • 35 yard slab
  • 2 guys screeing, 2 guys behind them moving concrete around - 4 person job
  • Batched at 6.
  • Arrived on site at 7.
  • Finished pour 8:30
  • Start mag floats on edges at 10:20 AM
  • Edger at 10:30
  • 2:15 hours after pour ready to walk on, sinks about 1/8"
  • Float blades first, finish trowel blades second. Take off the float blades to use the finish blades.
  • Power trowel started at 11 am at 4 hours after start of pour - with float blades first. Only 1+ hour for power trowel. When start power trowel, your feet sink in about 1/8"
  • Notes: effectively, go from screeing step - to edger - to power trowel. Edger can be avoided. Power trowel does both float and trowel.

Tools

  • Concrete Placer - [14]
  • Clevis to button handle adapter - [15]
  • Bull float handle - 6' extensions - [16]
  • Magnesium Bull float 48" - [17]
  • Easy tilt bull float handle adapter [18]
  • Fresno trowel [19]

Links

Retrieved from "https://wiki.opensourceecology.org/index.php?title=Open_Source_Concrete_Work&oldid=260506"