▁conditions ▁and ▁cond ens ation , ▁can ▁react ▁with ▁sul ph ate ▁ ions ▁to ▁cause ▁eff l ores c ence ; ▁po zz olan ic ▁chem istry ▁reduces ▁the ▁amount ▁of ▁Port land ite ▁available , ▁to ▁reduce ▁eff l ores c ence . ▁| } ▁ ▁Self - he aling ▁properties ▁ ▁Natural ▁po zz olan ic ▁re actions ▁can ▁cause ▁mort ars ▁and ▁con cre tes ▁containing ▁these ▁materials ▁to ▁" self - he al ". ▁The ▁E MC ▁Activ ation ▁process ▁can ▁at ▁times ▁increase ▁the ▁lik elihood ▁of ▁the ▁occurrence ▁of ▁these ▁po zz olan ic ▁re actions . ▁The ▁same ▁t endency ▁been ▁noted ▁and ▁studied ▁in ▁the ▁various ▁supporting ▁structures ▁of ▁H ag ia ▁Soph ia ▁built ▁for ▁the ▁By z antine ▁em peror ▁Justin ian ▁( now , ▁Ist an bul , ▁Turkey ). ▁ ▁There , ▁in ▁common ▁with ▁most ▁Roman ▁c ements , ▁mort ars ▁compr ising ▁high ▁amounts ▁of ▁po zz ol ana ▁were ▁used ▁— ▁in ▁order ▁to ▁give ▁what ▁was ▁thought ▁to ▁be ▁an ▁increased ▁resistance ▁to ▁the ▁stress - effect s ▁caused ▁by ▁earth qu akes . ▁ ▁Range ▁of ▁characteristics ▁Con cre tes ▁made ▁from ▁ener get ically ▁modified ▁c ements ▁can ▁be ▁designed ▁to ▁exhib it ▁superior ▁strength ▁and ▁dur ability ▁or ▁to ▁exhib it ▁rapid ▁and ▁ult ra - rap id ▁hard ening . ▁This ▁depends ▁upon ▁the ▁" po zz olan ic " ▁characteristics ▁of ▁the ▁raw ▁material ▁that ▁is ▁employed ▁to ▁make ▁it .