Cov tshuaj tiv thaiv alkali-silica, feem ntau hu ua "kev mob qog noj ntshav", yog cov tshuaj tiv thaiv o uas tshwm sim dhau sijhawm hauv cov pob zeb ntawm cov alkaline cement paste thiab cov reactive amorphous silica pom nyob rau hauv ntau yam sib sau ua ke, muab txaus. noo noo.
Dab tsi ua rau alkali silica cov tshuaj tiv thaiv?
Ua rau alkali-silica cov tshuaj tiv thaiv
ASR yog tshwm sim los ntawm cov tshuaj tiv thaiv ntawm hydroxyl ions hauv alkaline cement pore tov nyob rau hauv cov pob zeb thiab cov ntaub ntawv reactive ntawm silica nyob rau hauv cov aggregate (xws li: chert, quartzite, opal, strained quartz crystals).
YPuas silica react nrog alkali?
Alkali-silica cov tshuaj tiv thaiv (ASR) yog ntawm kev txhawj xeeb ntxiv vim tias cov khoom sib xyaw uas muaj cov khoom siv silica muaj ntau dua. Nyob rau hauv ASR, aggregates uas muaj qee cov ntaub ntawv ntawm silica yuav hnov mob nrog alkali hydroxide hauv pob zeb los tsim cov gel uas swells raws li nws adsorbs dej los ntawm ib puag ncig cov cement paste lossis ib puag ncig.
Cov tshuaj tiv thaiv alkali silica tshwm sim li cas hauv pob zeb?
Qhov laj thawj ntawm ASR yog cov tshuaj tiv thaiv nruab nrab ntawm cov alkaline cement's hydroxyl ions thiab qee qhov sib sau ua ke cov ntaub ntawv ntawm silicaQhov no tsim cov hygroscopic gel uas nthuav dav rau kev nqus dej, imposing. siab rau cov pob zeb ib puag ncig thiab ua rau nws tsis muaj zog nyob rau hauv ib txoj kev zoo ib yam li kev ua kom khov-thaw.
Vim li cas alkali silica cov tshuaj tiv thaiv tsim kev puas tsuaj rau pob zeb?
Nws ua kom nthuav dav sodium lossis potassium nplua nuj (alkali) silica gel uas muaj peev xwm nqus tau cov dej noo ntxiv thiab nthuav dav. Thaum no expansive gel kiag li puv lub pore system nyob rau hauv lub pob zeb nws exerts ntau tensile stresses (1, 2, 3, 4). Qhov tshwm sim yog hnyav tawg ntawm cov pob zeb.
