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

What is Mortar?

Applications 3D printing cementous mixtures Robotic brick masons

Colloidal Silica * Nano SiO2 particles that have been pre- suspended in liquid

Research Design 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 C8-1% 818 393 16.53 3,483 C8-2% 810 384 33.06 3,467 C8-5% 787 362 78.50 3,422 C30-1% 382 27.26 3,473 C30-2% 55.06 3,445 C30-5% 309 131 3,369

Cembinder Cembinder 8 Cembinder 30 Products of Akzo-Nobel™ SiO2 30% Avg. Particle Size 6 nm W/C Ratio .3-.5 Addition Rate 1-3% Cembinder Cembinder 8 Cembinder 30 Products of Akzo-Nobel™ Cembinder 8 SiO2 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) (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.

Flow Table Results Mix Avg. Diameter Flowability Control 9.19in 126.6% C8-1% 8.56in 114.1% C8-2% 8.69in 117.2% C8-5% 7.66in 91.4% C8-8% 6.66in 66.4% C30-1% 7.31in 82.8% C30-2% 7.19in 79.7% C30- 5% 5.56in 39.1% C8-5%-SP 8.88in 121.9% C8-8%-SP 7.94in 98.4% Flow Table Results Flowability =[(Avg. Diameter-4in)/4in]*100

Designed Mixes

Vicat Needle Results Mix Initial Set Final Set Control 125 min 170 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 SiO2 .

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

Printing Results Control Mix- cracks (fractures) in the base C8-5% 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% SiO2 Superplasticizers have little affect on compressive strengths except when silica concentration is above 5% by weight of cement Smaller SiO2 particles slightly improve setting time while drastically reducing flowability. Compressive strength are higher for all silica containing mixtures.