Effect of different forms of silica on the physical and mechanical properties of gypsum plaster composites


  • A. A. Khalil National Research Centre
  • A. Tawfik National Research Centre
  • A. A. Hegazy National Research Centre
  • M. F. El-Shahat Aim Shams Univ.




composites, gypsum plaster, silica, physical and mechanical properties, building units


Gypsum plaster/silica composites prepared by dry blending (0.2-10 %) natural sand, silica fume or silica gel and subsequently hydrated. Their physical and mechanical properties, including normal consistency, setting time, apparent porosity, bulk density and compressive strength, were determined after hydration for 7- and 28-days. The results indicated that adding different forms of silica lowered the bulk density and increased the normal consistency, setting time, apparent porosity and, to some limited extent, compressive strength of the composites. This improvement in properties can be attributed to the existence of silica in the interstitial pores in the hardened plaster matrices. While most of the composites revealed only scant rises in compressive strength, their composition was beneficial in so far as it included either a readily available low-cost constituent (sand) or industrial by-products. Consequently, the formed plaster-silica composites are of economic value, contribute to a cleaner environment by minimizing waste and can be used for applications where high porosity, lightweight units are required or recommended for low-cost buildings.


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(1) McDowell, S.J. "Development of Proposed Standards and Tests for Plaster of Paris in Ceramic Industries" Bull. Am. Cer. Soc. 14 (1935) 229-235.

(2) Khalil, A.A.; Gad, G.M. "Mineral and chemical constitutions of the UAR gypsum raw materials". Indian Ceramics, 16 (1972) 173 - 177.

(3) Said, R. "The Geology of Egypt" A. A.Balkama, Rotterdam (1990).

(4) Gartner, E M: "Cohesion and expansion in polycrystalline solids formed by hydration reactions: The case of gypsum plasters". Cem. Concr. Res. 39 (2009) 289–295. http://dx.doi.org/10.1016/j.cemconres.2009.01.008

(5) Bas_pinar, S. M.; Kahraman, E. "Modifications in the properties of gypsum construction element via addition of expanded macroporous silica granules". Construction and Building Materials 25 (2011) 3327–3333. http://dx.doi.org/10.1016/j.conbuildmat.2011.03.022

(6) Combe, E. C.; Smith, D. C. "Some Properties of Gypsum Plaster" . J. Brit. Dent., 17 (1964) 237-245.

(7) Peters, C. P.; Hines, J. L.; Bachus, K. N.; Craig M. A.; Bloebaum, R. D. "Biological Effect of Calcium Sulfate as Bone Graft Substitute in Ovine Metaphyseal Defects" J. Biomed. Mater. Res. A., 76, No3 (2005) 456-462

(8) Craig, R. G. "Restorative Dental Materials" 7th Edition, St. Louis, Toronto, and Princeton. The C.V. Mospy comp., (1989) 303-330.

(9) Papageorgiou, A.; Tzouvalas, G.; Tsimas, S. "Use of Inorganic Setting Retarders in Cement Industry" Cem. Concr. Res., 27 (2005) 183- 189.

(10) El-Maghraby, H.F.; Gedeon, O.; Khalil, A.A. "Formation and Characterization of Poly(vinyl alcohol – co – vinyl Acetate – co-itaconic Acid/ Plaster Composites: part II: Composite Formation and Characteristics" Ceramic Silikaty 51, nº 3 (2007) 168-172.

(11) Arikan, M.; Sobolev, K. "The Optimization of Gypsum Based Composite Material" Cem. Concr. Res., 12 (2002) 1725-1728. http://dx.doi.org/10.1016/S0008-8846(02)00858-X

(12) Khalil, A.A.; Abdel kader, A. H. "Preparation and physicomechanical Properties of Gypsum Plaster-Agro FiberWastes Composites" Interceram Int. J. Refractories Manual (Special Technologies) 21 (2010), 62-67.

(13) Murat, M.; Attari, A. "Modification of some physical properties of gypsum plaster by addition of clay minerals", Cem. Concr. Res., 2 (1991) 378–87. http://dx.doi.org/10.1016/0008-8846(91)90019-E

(14) Wen, L.; Yu-he, D.; Mei, Z.; Ling, X.; Qian, F. "Mechanical properties of nano SiO2 filled gypsum particle board" Trans Nonferrous Metals Soc China 16 (2006), 361-364. http://dx.doi.org/10.1016/S1003-6326(06)60210-0

(15) Fu, X.; Chung, D.D.L. "Effects of silica fume, latex, methylcellulose, and carbon fibers on the thermal conductivity and specific heat of cement paste." Cem. Concr. Res., 27, nº 12 (1997), 1799-1804. http://dx.doi.org/10.1016/S0008-8846(97)00174-9

(16) Shebl, S.S.; Seddeq, H. S.; Aglan, H. A. "Effect of micro-silica loading on the mechanical and acoustic properties of cement pastes" Construction and Building Materials 25 (2011), 3903-3908. http://dx.doi.org/10.1016/j.conbuildmat.2011.04.021

(17) Ogawa, K.; Uchikawa, H.; Takemoto, K.; Yasui, I. "The mechanism of the hydration in the system C3S- pozzolana", Cem. Concr. Res., 10 (1980) 683-696. http://dx.doi.org/10.1016/0008-8846(80)90032-0

(18) Khalil, A.A. "Gypsum Plaster: II-Constitution and Properties of the Prepared β-Hemihydrates" J. Appl. Chem. Biotechnol. 22, nº 6 (1972), 703-709. http://dx.doi.org/10.1002/jctb.5020220609

(19) Khalil, A. A.; Saniour, S.H. "Characterization of the prepared dental gypsum plasters" Interceram 46, nº 4, (1997) 250-253.

(20) Ohama, Y.; Oikawa, K.; Terata, O. "Process Technology of Polystyrene Gypsum Mortar Systems" Proc. Jpn. Congr. Mater. Res., 22 (1979), 348-351.

(21) Khalil, A.A.; Tawfik, A.; Hegazy, A. A.; El-Shahat, M. F. "Gypsum plaster composites: I-Characterization of the starting materials" Egypt. J. of Appl. Sci. ISSN 1110-1571, 27, nº 9 (2012) , 746-760.

(22) ASTM, Standard Methods for Physical Testing of Gypsum, C472-99(2009).

(23) Khalil, A.A.; Mohamed, A.I. "Firing Characteristics, phase composition and physicomechanical properties of Tushka Clay bodies fired at different temperatures" Interceram 60, nº 1, (2011)20-24.




How to Cite

Khalil, A. A., Tawfik, A., Hegazy, A. A., & El-Shahat, M. F. (2013). Effect of different forms of silica on the physical and mechanical properties of gypsum plaster composites. Materiales De Construcción, 63(312), 529–537. https://doi.org/10.3989/mc.2013.04312



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