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

2. What is Mortar?

3. Applications
3D printing cementous mixtures
Robotic brick masons

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

5. Research Design
Design Mortar Mix
Prepare Samples
Test
Compare Results

6. 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

7. 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%

8. 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)

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

10. 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

11. 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.

12. 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

15. Designed Mixes

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

17. 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 .

19. 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.

20. 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

21. 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.