Flexural Behavior of Lightweight Concrete Reinforced with Basalt Fiber Bars

What is Basalt Rebar? Basalt rock is a volcanic rock deposit

Melted at 1700°C and extruded into thin fibers

Final product is 80% fiber and 20% epoxy bonding agent

History of Basalt Rebar

• Manufactured in the U.S. prior to WWII• Used in Russia during cold war for defense

and aerospace• Declassified for civilian use in the U.S. in

1995• Increasing efforts to commercialize and

lower cost

Overview of Analysis

Analyze the flexural behavior of lightweight concrete reinforced with Basalt Rebar. This task is to be achieved by studying:• Load - Deflection behavior• Concrete strain• Basalt rebar strain• Comparison with steel reinforcement• Comparison of non-linear finite element

analysis

Why Research Basalt Rod Reinforcement? Less than 1/3 the weight of steel Non-corrosive Stronger tensile strength than that of steel Non-reactive Non-conductive

Laboratory Procedures Concrete mix design Beam design and construction Testing

Mix Design Lightweight concrete =120 pcf Concrete Strength at 28 day = 6000 psi

Per 1yd^3

Sand Ne Solite Genevieve Cement

Chicago Slag

Microsilica Cementious Water

1450 935 657.5 100 25 782.5 210.5

Mixture Proportions

Beam Design 2 beams each with reinforcement of…

2 – 8 mm bars Cross sectional area = 100.5 mm2

= 0.16 in2

2 – 10 mm bars Cross sectional area = 157.1 mm2

= 0.24 in2

3 – 8 mm bars Cross sectional area = 150.8 mm2

= 0.23 in2

3 – 10 mm bars Cross sectional area = 235.6 mm2

= 0.37 in2

Length = 12 ft, width = 8 in, depth = 12 in

Testing

Testing 4 point flexural test Clear span length 11ft Electrical resistance strain gauges

attached to basalt reinforcement and compressive face of concrete

Linear voltage deflection transducer measured vertical deflection at center of beam

Loading Setup

Testing Results Load vs. Deflection Load vs. Reinforcement Strain Load vs. Concrete Compressive Strain

Load vs Deflection

Load Vs Reinforcement Strain

Load Vs. Concrete Compressive Strain

Performance Comparison with Steel Reinforcement

Load Vs Reinforcement Strain