Dr Rackel San Nicolas

  • Room: Level: 04 Room: 418
  • Building: Engineering Block D
  • Campus: Parkville

Research interests

  • Alkali activated materials for constructions (Alkali-activation, Geopolymers, Constructions, Slag, Fly ash)
  • Durability of concrete (Durability, Additions, Performance-based approach)
  • Smart materials for construction (Self healing concretes, bioconcrete)


Rackel San Nicolas is working to develop reliable test methods for sustainable materials for constructions durability, and to understand the relationship between sustainable concretes microstructure, mechanical, structural properties and durability. She is also developing new smart materials for construction, as biomodified self-healing concrete for examples, using her multidisciplinary background and network.She is working in close collaboration with several industries.

Recent publications

  1. Kristombu Baduge, S.; Mendis, P.; San Nicolas, R.; Nguyen, K.; Hajimohammadi, A. Performance of lightweight hemp concrete with alkali-activated cenosphere binders exposed to elevated temperature. Construction and Building Materials. Elsevier BV. 2019, Vol. 224, pp. 158-172. DOI: 10.1016/j.conbuildmat.2019.07.069
  2. Walkley, B.; Rees, G.; San Nicolas, R.; Van Deventer, J.; Hanna, J.; Provis, J. Nanostructural development of synthetic C-(N)-A-S-H gels revealed by multinuclear MQMAS NMR. . Ecole polytechnic federal of Lausanne. 2018.
  3. Walkley, B.; Rees, GJ.; Nicolas, RS.; Van Deventer, JSJ.; Hanna, JV.; Provis, JL. New Structural Model of Hydrous Sodium Aluminosilicate Gels and the Role of Charge-Balancing Extra-Framework AI. The Journal of Physical Chemistry C. AMER CHEMICAL SOC. 2018, Vol. 122, Issue 10, pp. 5673-5685. DOI: 10.1021/acs.jpcc.8b00259
  4. Ren, J.; Zhang, L.; San Nicolas, R. Degradation of alkali-activated mortars in phosphoric acid-rich solution. . University of Southern Queensland. 2017.
  5. San Nicolas, RVR.; Walkley, B.; Van Deventer, JSJ. Fly ash-based geopolymer chemistry and behavior. . Elsevier. 2017, pp. 185-214. DOI: 10.1016/B978-0-08-100945-1.00007-1
  6. Rupasinghe, M.; Nicolas, RS.; Mendis, P.; Sofi, M.; Tuan, N. Investigation of strength and hydration characteristics in nano-silica incorporated cement paste. Cement and Concrete Composites. ELSEVIER SCI LTD. 2017, Vol. 80, pp. 17-30. DOI: 10.1016/j.cemconcomp.2017.02.011
  7. Walkley, B.; Provis, J.; Rees, G.; San Nicolas, R.; Hanna, J.; Van Deventer, J. Molecular structure of alkali-activated cements as determined by solid state 27Al and 23Na MQMAS NMR. . University College London. 2017, pp. 36-36.
  8. Walkley, B.; Nicolas, RS.; Sani, M-A.; Bernal, SA.; Van Deventer, JSJ.; Provis, JL. Structural evolution of synthetic alkali-activated CaO-MgO-Na2O-Al2O3-SiO2 materials is influenced by Mg content. Cement and Concrete Research. PERGAMON-ELSEVIER SCIENCE LTD. 2017, Vol. 99, pp. 155-171. DOI: 10.1016/j.cemconres.2017.05.006
  9. Bernal, SA.; San Nicolas, R.; Van Deventer, JSJ.; Provis, JL. Alkali-activated slag cements produced with a blended sodium carbonate/sodium silicate activator. Advances in Cement Research. ICE PUBLISHING. 2016, Vol. 28, Issue 4, pp. 262-273. DOI: 10.1680/jadcr.15.00013
  10. Un, CH.; Sanjayan, JG.; San Nicolas, R. Comparison of creep behaviour of geopolymer concrete and OPC concrete. Mechanics of Structures and Materials: Advancements and Challenges - Proceedings of the 24th Australasian Conference on the Mechanics of Structures and Materials, ACMSM24 2016. CRC Press (Taylor & Francis Group). 2016, pp. 437-442.
  11. Walkley, B.; San Nicolas, R.; Sani, M-A.; Rees, GJ.; Hanna, JV.; Van Deventer, JSJ.; Provis, JL. Phase evolution of C-(N)-A-S-H/N-A-S-H gel blends investigated via alkali-activation of synthetic calcium aluminosilicate precursors. Cement and Concrete Research. PERGAMON-ELSEVIER SCIENCE LTD. 2016, Vol. 89, pp. 120-135. DOI: 10.1016/j.cemconres.2016.08.010
  12. Walkley, B.; San Nicolas, R.; Sani, M-A.; Gehman, JD.; Van Deventer, JSJ.; Provis, JL. Phase evolution of Na2O-Al2O3-SiO2-H2O gels in synthetic aluminosilicate binders. Dalton Transactions. ROYAL SOC CHEMISTRY. 2016, Vol. 45, Issue 13, pp. 5521-5535. DOI: 10.1039/c5dt04878h
  13. Jayalath, A.; San Nicolas, R.; Sofi, M.; Shanks, R.; Ngo, T.; Aye, L.; Mendis, P. Properties of cementitious mortar and concrete containing micro-encapsulated phase change materials. Construction and Building Materials. ELSEVIER SCI LTD. 2016, Vol. 120, pp. 408-417. DOI: 10.1016/j.conbuildmat.2016.05.116
  14. Walkley, B.; San Nicolas, R.; Sani, M-A.; Gehman, JD.; Van Deventer, JSJ.; Provis, JL. Synthesis of stoichiometrically controlled reactive aluminosilicate and calcium-aluminosilicate powders. Powder Technology. ELSEVIER SCIENCE BV. 2016, Vol. 297, pp. 17-33. DOI: 10.1016/j.powtec.2016.04.006
  15. Tennakoon, C.; Nicolas, RS.; Sanjayan, JG.; Shayan, A. Thermal effects of activators on the setting time and rate of workability loss of geopolymers. Ceramics International. ELSEVIER SCI LTD. 2016, Vol. 42, Issue 16, pp. 19257-19268. DOI: 10.1016/j.ceramint.2016.09.092
  16. Tennakoon, C.; Sagoe-crentsil, K.; San Nicolas, R.; Sanjayan, JG. Characteristics of Australian brown coal fly ash blended geopolymers. Construction and Building Materials. ELSEVIER SCI LTD. 2015, Vol. 101, pp. 396-409. DOI: 10.1016/j.conbuildmat.2015.10.089
  17. Un, CH.; Sanjayan, JG.; San Nicolas, R.; Van Deventer, JSJ. Creep behaviour of geopolymer. . ICPMAT. 2015.
  18. Walkley, B.; San Nicolas, R.; Bernal, SA.; Provis, J.; Van Deventer, JSJ. Effect of MgO incorporation on the structure of synthetic alkali-activated calcium aluminosilicate binders. . Concrete Institute of Australia. 2015, pp. 1026-1032.
  19. Van Deventer, JSJ.; San Nicolas, R.; Ismail, I.; Bernal, SA.; Brice, DG.; Provis, JL. Microstructure and durability of alkali-activated materials as key parameters for standardisation. Journal of Sustainable Cement-Based Materials. Taylor & Francis. 2015, Vol. 4, Issue 2, pp. 116-128. DOI: 10.1080/21650373.2014.979265
  20. Un, CH.; Sanjayan, JG.; San Nicolas, R.; Van Deventer, JSJ. Mini-beam test for assessing the creep trend of paste, mortar and concrete. CONCREEP 10. American Society of Civil Engineers. 2015, pp. 1350-1359. DOI: 10.1061/9780784479346.160

View a full list of publications on the University of Melbourne’s ‘Find An Expert’ profile