en Research Paper Research Paper <span style="font-size:11pt"><span style="line-height:200%"><span style="text-autospace:none"><span style="font-family:Calibri,sans-serif"><a name="_Hlk126074938"><span style="color:#000000;"><span lang="EN-US" style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" times="">In this study, the potential of calcined montmorillonite as a primary precursor for one-part alkali-activated cement incorporated with high percentage of limestone, is evaluated. Comparative studies on the properties of the sodium silicate activated metakaolin-limestone and metamontmorillonite-limestone fresh and hardened cement pastes depending on several formulation and processing parameters (precursor nature, dosages of limestone and alkali reactant, curing conditions) showed that metamontmorillonite exhibits reactivity comp</span></span></span></span></a><span style="color:#000000;"><span lang="EN" style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" times="">arable to that of metakaolin in the studied cement systems. </span></span></span><span lang="EN-US" style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" times="">The mechanical performance of o</span></span></span><span lang="EN" style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" times="">ptimal alkali-activated cement formulations consisted of 20-30% of </span></span></span><span lang="EN-US" style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" times="">metamontmorillonite</span></span></span><span lang="EN" style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" times=""> and 70-80% of limestone </span></span></span><span lang="EN-US" style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" times="">is provided by both reactivity of metamontmorillomite under sodium silicate activation and the filler, nucleation, and chemical effects of the raw limestone.</span></span></span> <span lang="EN-US" style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" times="">The reaction products and microstructures of alkali-activated metamontmorillonite-limestone cement-based hardened pastes were investigated using thermal, XRD, and SEM/EDS analyses.&nbsp;&nbsp;&nbsp; </span></span></span></span></span></span></span></span><br> <span style="color:#000000;">&nbsp;</span> metakaolin,metamontmorillonite,alkali,,cement 1 7 http://ijmse.iust.ac.ir/browse.php?a_code=A-10-4948-1&slc_lang=en&sid=1 Nailia Rakhimova nailia683@gmail.com 1800319475328460017344 1800319475328460017344 Yes Kazan state university of architecture and engineering Vladimir Morozov vladimir.morozov@kpfu.ru 1800319475328460017345 1800319475328460017345 No Kazan Federal University Aleksey Eskin eskin.aleksey@gmail.com 1800319475328460017346 1800319475328460017346 No Kazan Federal University Bulat Galiullin taubulat@gmail.com 1800319475328460017347 1800319475328460017347 No Kazan Federal University