Corpus sync: neutrality remakes, note hygiene, datasheet relocation, transformer-split cross-refs
---
title: Concrete Curing and Finishing
…161 unchanged lines
## Curing Compound Compatibility with Floor Finishes {toc}
−### A permanent membrane-forming curing compound forms a film on the concrete surface that prevents bond of polished-concrete densifiers, tile thin-set, self-leveling underlayment, resilient flooring adhesive, and resinous coatings; if applied to a slab scheduled for any of these finishes, the film must be mechanically removed before the finish is installed, adding cost and schedule. {note}
+### A permanent membrane-forming curing compound forms a film on the concrete surface that prevents bond of polished-concrete densifiers, tile thin-set, self-leveling underlayment, resilient flooring adhesive, and resinous coatings; if applied to a slab scheduled for any of these finishes, the film must be mechanically removed before the finish is installed, adding cost and schedule.
### Where a slab is scheduled to receive polished concrete, ceramic or stone tile set in thin-set, resilient flooring, or a resinous coating, a permanent white-pigmented membrane-forming compound (ASTM C309 Type 2) shall not be used.
…90 unchanged lines
### Polyethylene curing sheet shall be clear or white film of nominal 6-mil thickness, placed over the wetted surface or over saturated burlap, lapped at joints, and weighted or taped to prevent moisture loss and wind uplift.
−### White polyethylene sheet should be used in lieu of clear film on sun-exposed placements to reduce solar heat gain and the discoloration that mottled clear-film contact can cause.
−
−### Burlap-polyethylene laminate curing blankets shall be pre-soaked before placement and kept continuously in contact with the surface for the curing period.
−
−### Wet curing by saturated burlap or soaker hose shall keep the surface continuously moist for the full curing period.
−
−### Intermittent wetting that allows the surface to dry between applications causes surface crazing and is not continuous curing. {note}
−
```datasheet
label: Polyethylene curing sheet
…5 unchanged lines
```
+### White polyethylene sheet should be used in lieu of clear film on sun-exposed placements to reduce solar heat gain and the discoloration that mottled clear-film contact can cause.
+
+### Burlap-polyethylene laminate curing blankets shall be pre-soaked before placement and kept continuously in contact with the surface for the curing period.
+
+### Wet curing by saturated burlap or soaker hose shall keep the surface continuously moist for the full curing period.
+
```datasheet
label: Wet curing material
…7 unchanged lines
```
+### Intermittent wetting that allows the surface to dry between applications causes surface crazing and is not continuous curing. {note}
+
## Temperature-Protection Blankets and Evaporation Retarders {toc}
…36 unchanged lines
## The curing period protects the near-surface zone, which lags the core in strength and durability and benefits from the full period regardless of cylinder breaks. {note}
+## The minimum curing duration shall be specified based on the cement type, supplementary cementitious material content, and durability requirements of the concrete placed.
+
```datasheet
label: Minimum curing duration
…7 unchanged lines
```
+## The cementitious system used in the concrete mix shall be specified, since it governs the minimum curing duration required.
+
```datasheet
label: Cementitious system (drives duration)
…13 unchanged lines
## Where the evaporation rate determined from the ACI 305 nomograph exceeds 0.20 lb/ft²/hr, protective measures shall be implemented before and during finishing.
−## Hot weather protective measures shall include one or more of the following as required to control evaporation: fogging upwind of the placement, erection of windbreaks, sun shading, application of evaporation retarder, and scheduling the placement for night or early morning.
−
−## Fresh concrete temperature at the point of discharge shall not exceed 95°F unless a lower limit is specified for mass or high-performance concrete.
−
−## Curing shall begin as early as finishing permits in hot weather.
−
−## The period between final finishing and the start of curing is when surface drying does the most damage. {note}
−
```datasheet
label: Evaporation rate trigger for protective measures
…6 unchanged lines
```
−```datasheet
−label: Maximum fresh concrete temperature at discharge
−type: range
−unit: °F
−min: 85
−max: 95
−step: 5
−default: 95
−```
+## Hot weather protective measures shall include one or more of the following as required to control evaporation: fogging upwind of the placement, erection of windbreaks, sun shading, application of evaporation retarder, and scheduling the placement for night or early morning.
```datasheet
…11 unchanged lines
```
+## Fresh concrete temperature at the point of discharge shall not exceed 95°F unless a lower limit is specified for mass or high-performance concrete.
+
+```datasheet
+label: Maximum fresh concrete temperature at discharge
+type: range
+unit: °F
+min: 85
+max: 95
+step: 5
+default: 95
+```
+
+## Curing shall begin as early as finishing permits in hot weather.
+
+## The period between final finishing and the start of curing is when surface drying does the most damage. {note}
+
# Cold Weather Curing {toc}
…48 unchanged lines
## Forms shall remain in place for a minimum of 12 hours on non-structural surfaces and 24 hours on structural walls and columns before form removal for the purpose of applying a curing compound, except as the Engineer of Record directs for the specific mix and conditions.
−## The form-removal sequence shall be coordinated with the curing plan so that stripping does not interrupt the required curing period.
−
−## Stripping schedule and curing duration are coordinated requirements, not independent ones. {note}
−
```datasheet
label: Minimum form-in-place time before compound application
…6 unchanged lines
```
+## The form-removal sequence shall be coordinated with the curing plan so that stripping does not interrupt the required curing period.
+
+## Stripping schedule and curing duration are coordinated requirements, not independent ones. {note}
+
# Surface Finishing {toc}
…4 unchanged lines
### Each surface shall receive the finish indicated in the finish schedule; where no finish is scheduled for an interior slab, a steel-troweled finish shall be provided, and where none is scheduled for an exterior slab, a broom finish shall be provided.
−### Finishing operations shall not begin until the bleed water sheen has left the surface; premature finishing seals bleed water under the surface and produces a weak, dusting wear layer. {note}
+### Finishing operations shall not begin until the bleed water sheen has left the surface; premature finishing seals bleed water under the surface and produces a weak, dusting wear layer.
```datasheet
…185 unchanged lines
## A slab scheduled to receive a moisture-sensitive floor covering shall be tested for internal relative humidity in accordance with ASTM F2170 before the covering is installed, and the covering shall not be installed until the measured internal relative humidity is at or below the covering manufacturer's limit.
+```datasheet
+label: Moisture testing required before floor covering
+type: radio
+options:
+ - Required for all moisture-sensitive coverings
+ - Required where indicated
+ - Not required (bare or non-sensitive finish)
+default: Required for all moisture-sensitive coverings
+```
+
## The internal relative humidity limit shall be taken as 75% to 80% unless the floor-covering manufacturer specifies a different limit, in which case the manufacturer's limit shall govern.
−## A drying period shall be allowed after curing ends and before moisture testing; as a planning rule of thumb the period is on the order of 30 days per inch of slab thickness under favorable interior drying conditions, but the ASTM F2170 result, not the calendar, governs acceptance. {note}
−
```datasheet
label: Internal relative humidity limit (ASTM F2170)
…6 unchanged lines
```
−```datasheet
−label: Moisture testing required before floor covering
−type: radio
−options:
− - Required for all moisture-sensitive coverings
− - Required where indicated
− - Not required (bare or non-sensitive finish)
−default: Required for all moisture-sensitive coverings
−```
+## A drying period shall be allowed after curing ends and before moisture testing; as a planning rule of thumb the period is on the order of 30 days per inch of slab thickness under favorable interior drying conditions, but the ASTM F2170 result, not the calendar, governs acceptance. {note}