Evaluation of strengthening through stress relaxation testing of organo-modified montmorillonite reinforced cement mortars

It is demonstrated that the addition of organo-modified montmorillonite (OMMT) particles to cement mortars can enhance their microstructure as well as mechanical properties. A series of static compression and stress relaxation tests on cement mortars reinforced with various dosages of OMMT particles under different temperatures and imposed strains were conducted. The consistency of the test results, including pore size distributions obtained from mercury intrusion porosimetry measurements and activation energies determined from stress relaxation tests, reinforces the positive effects observed on the initial elastic modulus, compressive strength and strain exponent of cement mortars. It appears that an important step has been achieved in assessing the benefits of using organo-clays in concrete. Accordingly, the adequate dosage of OMMT particles introduced in cement mortars to give a higher elastic modulus, compressive strength and activation energy of stress relaxation is proposed here.