UTILIZATION OF POWDERED GYPSUM-WALLBOARD IN CONCRETE By Tarun R. Naik, Rakesh Kumar, Yoon-moon Chun, and Rudolph N. Kraus UWM-CBU, Milwaukee, USA Presented at the Second International Conference on Sustainable Construction Materials and Technologies, Università Politecnica delle Marche, Ancona, Italy, June 29, 2010. Center for By-Products Utilization
UWM Center for By-Products Utilization Reduce, reuse, recycle, and repair for sustainable developments. Minimize use of manufactured materials. Maximize environmental benefits: resource conservation, clean water, and clean air. Center for By-Products Utilization
Basic Approach WA$T € is wasted if you waste it, otherwise it is a resource. Resource is wasted if you ignore it and do not conserve it with holistic best practices and reduce societal costs. Resource is for the transformation of people and society. Focus on turning brown fields into green fields – Opportunities are here, now!! Center for By-Products Utilization
Basic Approach Recycle. Recycle as is. Recycle without additional processing, (i. e., without adding any cost to it). Avoided disposal leads to reduced GHGs. Center for By-Products Utilization
Progression: 21 st Century Solid Waste Management Recycling, sustainable infrastructures, sustainable management of resources (SMR), durable construction materials, global climate change, reduced GHGs, improved air quality, CO2 reduction & sequestration, and carbon offsets. Center for By-Products Utilization
INTRODUCTION • Gypsum-wallboard is one of the most common materials used in the construction of residential as well as office buildings in the United States. • It is mainly used as a surface layer on the interior of walls, partitions, and ceilings of the buildings. • It provides a surface that could be either easily painted or wall-papered. Center for By-Products Utilization
• It further adds to the fire resistance and sound reduction of the buildings. • In some cases it may also be used in exterior sheathing applications or in concrete formwork. • Gypsum-wallboard is commonly known as drywall, as the need for plaster is eliminated. • Over 30 billion square feet of gypsum-wallboard is manufactured each year in the U.S. Center for By-Products Utilization
ABSTRACT Two groups of concrete mixtures, one without sodium sulfate and other with sodium sulfate, as an activator, were made with recycled powdered gypsum-wallboard for this investigation. Center for By-Products Utilization
• Group 1 concrete mixtures were made using up to 20% of ASTM Class C fly ash and 20% powdered gypsum. • Group 2 contained up to 60% of fly ash and 20% of powdered gypsum by mass. Center for By-Products Utilization
EXPERIMENTAL INVESTIGATION Materials • ASTM Type I portland cement • ASTM Class C fly ash • Natural sand and crushed quartzite stone • Type A water reducing admixture (WRA) [ASTM C 494] • Gypsum-wallboard was obtained from two locations on the campus of University of Wisconsin- Milwaukee Center for By-Products Utilization
CONCLUSIONS • Up to 30% to 60% of cement in concrete mixtures could be successfully replaced with blends of Class C fly ash and powdered gypsum-wallboard. • Concrete mixtures containing up to 10% powdered gypsum-wallboard by mass of the total cementitious materials showed 28-day compressive strength equivalent to that of the control concrete mixtures. Center for By-Products Utilization
• Use of sodium sulfate as an activator was essential in improving the 1-day and 3-day strength of concrete containing blend of Class C fly ash and gypsum-wallboard. • A concrete mixture made with a cementitious blend of 40% cement, 50% Class C fly ash, and 10% powdered gypsum-wallboard showed a relatively large expansion (0.043%) during immersion in saturated limewater, but shrank during drying as much as it had expanded, resulting in very small net expansion at the age of 140 days. Center for By-Products Utilization
• A mortar mixture made with a cementitious blend of 40% cement, 50% Class C fly ash, and 10% powdered gypsum-wallboard showed much higher resistance to sulfate attack compared with the control mortar. • Use of powdered gypsum-wallboard in concrete causes a reduction in the quantity of cement clinkers required for manufacturing of cement, which would result in reduction of CO 2 emission and earning of carbon credits. Center for By-Products Utilization
RESOURCE CONSERVATION CLEAN WATER and CLEAN AIR “ The earth, the sea (water), and the air are the concern of every nation.” President John F. Kennedy, fall 1963, in a speech to the U.N. General Assembly. Center for By-Products Utilization
Spaceship Earth – La Bella Terra Center for By-Products Utilization
La bella terra Center for By-Products Utilization
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Thank you very much for your interest. Center for By-Products Utilization
Aabhar Tamaro, Afcharisto Poly, Arigatou Gozaimasu, Dziekuje , Maraming Salamat, Merci Beaucoup, Muchas Gracias, Grazie Molte, Muito Obrigado, Salamat, Shukriya, Spasibo, Thank you, Toda Raba. Center for By-Products Utilization
Proportions of Powder Materials Used for Concrete Mixtures CFNS- CFNS- CFNS- Mixture Designation C-2 CN-2 CFN-2 CFN-3 C-4 3 4 5 Laboratory mixture Ref-3 New-7 New-8 New-9 Ref-5 New-14 New-15 New-16 designation Cement (mass % of 100 90 70 60 100 60 40 20 Cm) Fly Ash (mass % of 0 0 20 20 0 33 50 60 Cm) New Gypsum- Wallboard (mass % of 0 10 10 20 0 7 10 20 Cm) Sodium Sulfate (mass 0 0 0 0 0 1 1 2 % of Cm) Cm: Cementitious materials (Cement + Fly Ash + Gypsum-Wallboard). Center for By-Products Utilization
Mixture Proportions and Fresh Concrete Properties of Mixtures Mixture Designation C-2 CN-2 CFN-2 CFN-3 C-4 CFNS-3 CFNS-4 CFNS-5 Cement (kg/m 3 ) 362 316 249 212 365 217 144 71 Class C Fly Ash, Weston 0 0 71 71 0 119 180 213 (kg/m 3 ) Powdered Gypsum- 0 35 35 71 0 25 36 71 Wallboard, New (kg/m 3 ) Water (kg/m 3 ) 164 164 170 153 163 154 153 157 Sand, SSD* (kg/m 3 ) 856 830 840 835 861 854 852 839 Crushed Stone, 19-mm max., 1030 999 1010 1010 1030 1030 1020 1010 SSD (kg/m 3 ) Sodium Sulfate, Na 2 SO 4 0 0 0 0 0 3.6 3.6 7.1 (kg/m 3 ) Water-Reducing Admixture 0 1.03 1.04 1.04 0 0 0 0 (L/m 3 ) Water-Cementitious Ratio, 0.45 0.47 0.48 0.43 0.45 0.43 0.42 0.44 W/Cm Slump (mm) 55 50 40 30 30 40 45 25 Slump, 30 minutes later (mm) 30 40 25 20 40 30 15 15 Air Content (%) 1.8 3.7 2.6 3.2 1.4 2.2 1.5 1.7 Air Temperature ( C) 23 24 23 24 23 23 23 24 Concrete Temperature ( C) 23 23 23 25 24 24 25 25 Density (kg/m 3 ) 2410 2340 2380 2350 2420 2400 2390 2370 Center for By-Products Utilization
Compressive Strength of Concrete Mixtures Age C-2 CN-2 CFN-2 CFN-3 C-4 CFNS-3 CFNS-4 (days) 1 16.8 11.1 4.2 3.9 15.9 5.8 3.8 3 30.1 19.7 17.4 13.2 30.2 23.7 17.8 7 35.4 23.2 26.5 15.4 34.7 30.1 29.7 28 44.8 28.5 41.4 21.1 40.8 41.5 42.0 91 50.8 41.9 50.1 28.9 51.5 44.3 49.7 Center for By-Products Utilization
Length Change of Series 1 Concrete Mixtures Length Change of Series 2 Concrete Mixtures Center for By-Products Utilization
SULFATE RESISTANCE Mixture Proportions and Flow of Mortar Mixtures Mixture Designation C-c C-b CFNS-1c CFNS-1b CFNS-2c CFNS-2b Laboratory mixture C-2 C-2 bar N-3 cube N-3 bar N-4 cube N-4 bar designation cube Cement (mass % of Cm) 100 100 60 60 40 40 Fly Ash (mass % of Cm) 0 0 33 33 50 50 New Gypsum-Wallboard 0 0 7 7 10 10 (mass % of Cm) Sodium Sulfate (mass % of 0 0 1 1 1 1 Cm) Cement (g) 500 740 300 444 200 296 ASTM Class C Fly Ash, (g) 0 0 165 244.2 250 370 Powdered Gypsum- 0 0 35 51.8 50 74 Wallboard, New (g) Sodium Sulfate, Na 2 SO 4 (g) 0 0 5 7.4 5 7.6 Water (g) 242 359 216 320.4 200 296.7 Water-Cementitious Ratio, 0.48 0.49 0.43 0.43 0.40 0.40 W/Cm Graded Standard Sand (g) 1375 2035 1375 2035 1375 2035 … … … Flow (mm) 190 185 191 Center for By-Products Utilization
Compressive Strength of Mortar (MPa) Age (days) C-c CFNS-1c CFNS-2c 1 14.8 4.5 1.1 4 31.4 17.4 11.1 … … 5 21.2 … … 5.125 16.7 … … 7 19.7 … … 24 25.0 28 39.6 31.6 Center for By-Products Utilization
Length Change of Mortar Bars (%) Age after immersion in 5% sodium sulfate C-b* CFNS-1b* CFNS-2b* solution (days) 7 0.007 0.016 0.006 14 0.013 0.024 0.009 21 0.016 0.028 0.009 28 0.020 0.033 0.009 42 0.027 0.044 0.011 56 0.034 0.063 0.010 *Number of specimens tested: Mixture C-b, five; Mixture N-1-b, six; and, Mixture N-2-b, three. Minimum three replicate test specimens required per ASTM C 1012. Center for By-Products Utilization
ECONOMICAL AND ENVIRONMENTAL APPRAISAL OF USING POWDERED GYPSUM IN CONCRETE • Environmental factors are moving against portland cement manufacturers due to large amount of CO 2 emissions created by the manufacture of portland cement. • Maximum use of recycled gypsum obtained from gypsum-wallboard in concrete and concrete products may reduce raw materials such as cement clinker and associated CO 2 emission. Center for By-Products Utilization
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