Structural Lightweight Concrete

Summary

• Partial replacement of fine aggregates

• Lightweight aggregates

• Fiberglass and Copper Slag

• Low concrete unit weight

• Meet the traditional concrete strength

• Compare lightweight concrete to traditional concrete

• Testing for tensile and compressive strength

• Applicable for structural purposes

Importance

• Reduce dead load on the building

• Smaller members (Ex. high rise building)

• Reduce overall costs

• Improve structural performance

• Longer life span of structure

• Improve fire resistance

• Improve thermal insulation

• Reduce transportation and placement costs

Pantheon – 2000 years.Lightweight Concrete Building

Lightweight ConcreteBridge

Procedure

• Standard practice for selecting proportions (ACI 211.1-91)

• Obtain materials

• 4 sets of 6 cylindrical specimens

• 24 concrete cylinders

• 1st set: Traditional concrete mixture

• 2nd set: Replace 50% fine aggregate with Copper Slag mixture

• 3nd set: Replace 50% fine aggregate with Fiberglass mixture

• 4th set: Replace 50% fine aggregate with both Copper Slag & Fiberglass

• Testing days: 14, 21, 28 (Compression & Tension)

Experiment

• Follow ASTM standards for the concrete mixing procedures

• Perform the slump test

• Strip cylinders from the molds after 24 hours

• Cure concrete cylinders by immersion in water

• Measure the weight

• Sulfur capping

• Test on Days 14, 21, 28

• Test compression strength on 12 cylinders

• Test tensile strength on 12 cylinders

Results

0 0.002 0.004 0.006 0.008 0.01 0.012 0.014 0.016 0.0180

5

10

15

20

25

30

35Compressive Test - Day 28

Fiber Copper Standard Fiber/Copper

STRAIN

STRE

SS [M

Pa]

• Traditional concrete surpassed 30 MPa @ 28 days mark

• Concrete mixture with Copper Slag had comparable results to traditional concrete

• Concrete mixture with Fiberglass had a decrease in both weight and strength

• Concrete mixture with both Copper Slag and Fiberglass had comparable strength to traditional concrete

Results

0 0.002 0.004 0.006 0.008 0.01 0.012 0.0140

0.5

1

1.5

2

2.5

3

3.5Tensile Test - Day 28

Fiber Copper Standard Fiber/Copper

STRAIN

STRE

SS [M

Pa]

• Concrete mixture with Fiberglass & Copper Slag surpassed the strength of traditional concrete

• All mixtures had comparable strength except Fiberglass

• Ductile & Brittle

Recommendations

• Increase number of concrete cylinders for all testing days

• Replace fine aggregates by 25-40% of copper slag to reduce the weight of the concrete cylinder

• Reduce amount of Fiberglass in fine aggregates (sand) up to 40%

• Replace fine aggregates with recycled bottle wastes

• Replace fine aggregates with Silica fume

References

• http://study.com/academy/lesson/finding-the-area-of-a-cylinder-formula-example.html [cylinder]• http://

romeonsegway.com/wp-content/plugins/widgetkit/cache/gallery/738/Pantheon-day-rome-on-segway-26234d1acc.jpg [Pantheon]

• http://carolynsmith.websitehabitat.com/wp-content/uploads/sites/14/2013/10/should-you-leave.jpg• http://www.magicreteaac.com/aac-blocks.html• http://www.hpcbridgeviews.org/images/Benicia-Martinez%20Photo1.jpg• http://www.lmj-a.com/P1010361.JPG• http://img.frbiz.com/pic/z1d321e1-0x0-0/strong_style_color_b82220_silica_strong_fume_microsilica.jpg• http://www.hiwtc.com/photo/products/11/00/01/105.jpg

References

• http://www.tgrmcc.com/product-details.php?pid=236• http://www.poraver.com/wp-content/uploads/Leichtbeton_Poraver02.jpg• http://www.stalite.com/uploads/EngineeringProperties.pdf• https://core.ac.uk/download/files/434/18264203.pdf• http://esatjournals.net/ijret/2015v04/i13/IJRET20150413027.pdf