Rapid Setting Cement Based Mortars Using Nano Materials

Rapid Setting Cement Based Mortars Using Nano Materials November 30, 2018 Advisor: Mohamed Zeidan Benjamin Boyett Blake Mc. Hugh Jordan Perez

s i t a h W ? r a t r o M

Applications • 3 D printing cementous mixtures • Robotic brick masons

Colloidal Silica * Nano Si. O 2 particles that have been presuspended in liquid

Research Design Mortar Mix Prepare Samples Test Compare Results

Mix Designs Mix Cement Sand Water Silica Total W/C S/C Control 826 2, 273 401 0. 00 3, 500 0. 49 2. 75 C 8 -1% 818 2, 273 393 16. 53 3, 483 0. 49 2. 75 C 8 -2% 810 2, 273 384 33. 06 3, 467 0. 49 2. 75 C 8 -5% 787 2, 273 362 78. 50 3, 422 0. 49 2. 75 C 30 -1% 818 2, 273 382 27. 26 3, 473 0. 49 2. 75 C 30 -2% 810 2, 273 362 55. 06 3, 445 0. 49 2. 75 C 30 -5% 787 2, 273 309 131 3, 369 0. 49 2. 75

Cembinder • Cembinder 8 • Cembinder 30 • Products of Akzo-Nobel™ Cembinder 30 Si. O 2 30% Avg. Particle Size 6 nm W/C Ratio. 3 -. 5 Addition Rate 1 -3% Cembinder 8 Si. O 2 50% Avg. Particle Size 35 nm W/C Ratio. 3 -. 5 Addition Rate 1 -5%

Flow Table Test • Fill mold ½ way; tamp 25 times. • Fill mold the rest of the way; tamp 25 times. • Remove mold; turn handle (drop table) 25 times in 15 seconds. • Take average of 4 diameters. • Flow = (100) x (Avg. Diameter of Mortar – (Inner Base Diameter of Mold)

Compression Test • Compressive Strength = Max Load / Surface Area (PSI) • Surface Area = Average cross-sectional area

Normal Consistency Test • Cement, Water, and Additives • Control, 1%, 2%, and 5% • Combine cement, water, and additives (if any). • Place ball into conical ring. • Normal Consistency = 10 mm of penetration after 30 seconds. Vicat Needle Plunger Rod Conical Ring

Vicat Needle Test • Initial Setting Time/Final Setting Time • Control, 1%, 2%, and 5%, • Use Normal Consistency Mix to determine initial and final setting time. • Begin a timer when water touches cement. • Initial Setting Time = The elapsed time from when water is added to cement to when the needle penetrates 25 mm or less. • Final Setting Time = The elapsed time from when water touches cement to when the needle no longer penetrates the Cementous mix.

w o Fl e l b a T s t l u s Re Mix Avg. Diameter Flowability Control C 8 -1% C 8 -2% C 8 -5% C 8 -8% C 30 -1% C 30 -2% C 30 - 5% C 8 -5%-SP 9. 19 in 8. 56 in 8. 69 in 7. 66 in 6. 66 in 7. 31 in 7. 19 in 5. 56 in 8. 88 in 126. 6% 114. 1% 117. 2% 91. 4% 66. 4% 82. 8% 79. 7% 39. 1% 121. 9% C 8 -8%-SP 7. 94 in 98. 4% Flowability =[(Avg. Diameter-4 in)/4 in]*100

Strength (PSI) Cembinder 8 Compressive Strength Results 9000 8000 7000 6000 5000 4000 3000 2000 1000 0 0 7 Control 14 21 Time (Days) C 8 -1% C 8 -2% C 8 -5% 28 C 8 -8%

Cembinder 30 Compressive Strength Results 8000 7000 Strength (PSI) 6000 5000 4000 3000 2000 1000 0 0 7 14 21 28 Time (Days) Control C 30 -1% C 30 -2% C 30 -5%

Setting Times 180 Time (min) 150 120 90 60 30 Designed Mixes 0 Control C 8 -1% C 8 -2% C 8 -5% C 30 -1% C 30 -2% C 30 -5%

Vicat Needle Results Mix Initial Set Final Set Control 125 min 170 min C 8 -1% 115 min 155 min C 8 -2% 107 min 152 min C 8 -5% 84 min 134 min C 30 -1% 106 min 150 min C 30 -2% 95 min 129 min

Superplasticizers • ADVA 190 • Product of Grace Concrete Products™ • Water reducing agent that retains workability of mortar. • Addition of superplasticizers allows us to maintain water-to-cement ratio while implementing higher concentrations of Si. O 2.

Colloidal Silica with Superplasticzer Results 9000 Compressive Strength (PSI) 8000 7000 6000 5000 4000 3000 2000 1000 0 0 5 10 15 20 25 Time (Days) C 8 -8% C 8 -5% C 8 -8%-SP C 8 -5%-SP Control

Printing Methods Mortar Gun Tamale Gun Grout Bag Failed due to over compaction at condensing point. Failed due to the pressure build up ceasing the flowability. Successful printing method. Condensing point can be massaged, allowing the mortar to flow at the rate of the person operating the bag.

Printing Results Control Mix- cracks (fractures) in the base C 8 -5% with 1. 1% SP (ADVA 190): - Best 28 day compressive strength & best all around mixture. - Little to no cracking

Research Summary • Experiment results display decreased flowability, decreased set times, and a increased compressive strengths with mortar mixtures containing up to 5% Si. O 2 • Superplasticizers have little affect on compressive strengths except when silica concentration is above 5% by weight of cement • Smaller Si. O 2 particles slightly improve setting time while drastically reducing flowability. • Compressive strength are higher for all silica containing mixtures.