1 / 18

Floor Flatness and Levelness

Floor Flatness and Levelness. Chapter 4. Chapter Topics. Measuring floor flatness and levelness The 10 ft (3m) straightedge method F-number system Factors affecting floor flatness and levelness. Definitions. Flatness Waviness or bumpiness of slab surface Smooth Levelness

ron
Download Presentation

Floor Flatness and Levelness

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Floor Flatness and Levelness Chapter 4

  2. Chapter Topics • Measuring floor flatness and levelness • The 10 ft (3m) straightedge method • F-number system • Factors affecting floor flatness and levelness

  3. Definitions • Flatness • Waviness or bumpiness of slab surface • Smooth • Levelness • Tilt or slope of slab surface

  4. Measuring Flatness and Levelness • Gap under a 10 ft straightedge • Oldest method • Measures only floor flatness; not levelness • Generally less satisfactory way of measuring • F-number system • Measures floor flatness and levelness • Must be used if floor exceeds 10,000 sf (ACI 301) • Measurements in accordance with ASTM standard

  5. The 10 ft Straightedge Method • Measured within 72 hours • Place an unleveled 10 ft straightedge on slab • Rests on two high spots • Measure gap at any point under straightedge between two high spots • 100% compliance with straightedge not realistic • Four out of five measurements more realistic

  6. F-Number System • Measure within 72 hours • FF – floor flatness FL – floor levelness • To get F-numbers • Measure surface elevations at 12 inches on-center • FF (bumpiness) calculated over 24 inch length • FL (tilt) calculated over 10 ft length • F-number pair always written in order: FF/FL • Higher F-numbers: the flatter and more level

  7. F-number System • Two different sets of F-numbers • Specified Overall Value (SOV) • Minimum Local Value (MLV) • Check specifications for requirements • ACI 302 provides recommendations • Measure in accordance with ASTM E 1155 • FL should not be measured on sloped slabs

  8. Factors Affecting Flatness • Concrete workability, finishability, and setting time; • The window of finishability • Sun, wind, rain, temperature extremes, • Amount of sunlight on the slab; • Timeliness of concrete delivery; • Uniformity of concrete slump, as delivered; • Consistency of final setting time; and • Site accessibility.

  9. Factors Affecting Levelness • Accuracy of edge forms • Quality of initial strikeoff • Wet screeds are harder to get higher FL • Smaller strip placements are easier to get higher FL

  10. End of Chapter 4

More Related