85:
634:
of the hydrated cement system. High alite reactivity is desirable in
Portland cement manufacture, and this is achieved by retaining, as far as possible, high temperature polymorphs, in crystals that are small, distorted and highly defective. Defects provide sites for initial water attack.
456:
contributes "late" strength, due to its lower reactivity. Alite is more reactive because of its higher Ca content, and the presence of an oxide ion in the lattice. During clinker grinding, first step of partial dissolution of
709:
phases in lime mortars. The only explanation for the discovery of these silicate phases not normally expected in lime mortar is that they have been formed by the hydration of calcium silicate such as
938:
R. K. Mishra; R. J. Flatt; H. Heinz (2013). "Force Field for
Tricalcium Silicate and Insight into Nanoscale Properties: Cleavage, Initial Hydration, and Adsorption of Organic Molecules".
313:
Tricalcium silicate is thermodynamically unstable below 1250°C, but can be preserved in a metastable state at room temperature by fast cooling: on slow cooling it tends to revert to
659:
impurities up to 25 – 30 wt. %). Hydraulic mortar or pre-Portland cement may have been occasionally produced on a small scale in this way during the
647:(25.2 wt. %) (see the hereabove table) may help to understand why in particular conditions, if a sufficiently high temperature is reached in a
766:
builders of this area were aware of the hydraulic properties of their lime mortar or intentionally developed its use after their fortuitous finding.
762:
are particularly rich in amorphous silica and exploited as building stone and for making lime mortar since very ancient ages. It is unknown if the
65:
702:
68:
in 1897 to a crystal identified in microscopic investigation of
Portland cement. Hatrurite is the name of a mineral that is substituted
452:
Alite is the major phase in
Portland cement responsible for setting and development of "early" strength. The other silicate,
914:
860:
827:
257:
ions or orthosilicate ions requires that electric charges be kept in balance. For instance, a limited number of
693:(Belgium) exhibit an unexpected hydraulic character as revealed by a mineralogical study made by Mertens
1018:
706:
623:
793:
540:
57:
17:
631:
444:
The polymorphs differ structurally by minor deformations from the basic hexagonal structure.
60:), typically with 3-4% of substituent oxides. It is the major, and characteristic, phase in
8:
652:
93:
27:
1013:
643:
The composition of alite rich in CaO (71.6 wt. %) and relatively poor in SiO
638:
984:
920:
910:
856:
833:
823:
690:
96:. It is a solid solution and contains minor amounts of other oxides besides CaO and
974:
967:"Minéralogie des silicates de calcium présents dans des mortiers anciens à Tournai"
947:
675:
668:
250:
1023:
966:
61:
979:
965:
Mertens, Gilles; Elsen, Jan; Laduron, Dominique; Brulet, Raymond (2006-12-31).
1007:
988:
924:
740:
258:
851:
Bournazel, Jean-Pierre; Malier, Yves; Regourd, Micheline
Moranville (1998).
837:
461:
S involves hydration of superficial oxide ions and leads to a hydroxylated C
698:
904:
331:
As the temperature changes, it passes through several polymorphic states:
817:
787:
756:
686:
651:
during enough time, alite can also be directly formed by pyrolizing only
612:
249:. In practice, the composition varies with the bulk composition of the
877:
951:
92:
The alite found in
Portland cement differs in composition from simple
763:
759:
744:
664:
648:
627:
290:
796: – Abbreviated notation for chemical formulas of common oxides
660:
639:
Alite as precursor of silicate phases found in medieval lime mortar
790: – High temperature rotating oven used for producing clinker
752:
748:
274:
254:
84:
937:
775:
453:
314:
672:
679:
506:
It reacts with water (roughly) according to the reaction:
964:
850:
1005:
685:This is likely the reason why some old medieval
289:) ions, provided that for each sulfate ion, two
214:Based on this, the formula can be expressed as
253:, subject to certain limits. Substitution of
79:
626:– "C-S-H-" – phase. It grows as a mass of
978:
83:
697:. (2006) who evidenced the presence of
1006:
902:
815:
88:Simplified crystal structure of alite.
811:
809:
853:Concrete, from material to structure
822:(2nd ed.). London: T. Telford.
739:S) formed at high temperature along
13:
909:. Academic Press. pp. 10–11.
806:
622:The hydrate is referred to as the
447:
14:
1035:
539:Which can also be written in the
884:. Hudson Institute of Mineralogy
940:Journal of Physical Chemistry C
958:
931:
896:
870:
844:
1:
308:
305:) ions are also substituted.
103:. A typical composition is:
769:
273:) ions can be replaced with
7:
781:
10:
1040:
980:10.4000/archeosciences.150
41:, sometimes formulated as
15:
663:epoch in locations where
655:(containing amorphous SiO
630:needles that provide the
80:Composition and structure
800:
707:calcium silicate hydrate
624:calcium silicate hydrate
339:
111:
108:
64:. The name was given by
903:Taylor, H.F.W. (1990).
816:Taylor, H.F W. (1997).
794:Cement chemist notation
541:cement chemist notation
58:cement chemist notation
855:. Rilem Publications.
89:
18:Alite (disambiguation)
973:. Varia (30): 61–65.
87:
26:is an impure form of
523:O → 3CaO·2SiO
16:For other uses, see
946:(20): 10417–10432.
774:See the article on
653:siliceous limestone
94:tricalcium silicate
28:tricalcium silicate
689:used to build the
90:
1019:Calcium compounds
952:10.1021/jp312815g
747:. In the area of
691:Tournai cathedral
442:
441:
212:
211:
1031:
999:
998:
996:
995:
982:
962:
956:
955:
935:
929:
928:
906:Cement Chemistry
900:
894:
893:
891:
889:
874:
868:
866:
848:
842:
841:
819:Cement Chemistry
813:
734:
719:
669:amorphous silica
667:was cemented by
618:
617:
616:
615:
609:
608:
598:
590:
589:
588:
587:
583:
582:
565:
535:
502:
500:
499:
496:
487:
486:
483:
478:
477:
474:
334:
333:
327:
304:
303:
302:
299:
288:
287:
286:
283:
272:
271:
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267:
248:
106:
105:
102:
75:
55:
47:
40:
1039:
1038:
1034:
1033:
1032:
1030:
1029:
1028:
1004:
1003:
1002:
993:
991:
963:
959:
936:
932:
917:
901:
897:
887:
885:
876:
875:
871:
863:
849:
845:
830:
814:
807:
803:
784:
772:
738:
733:
729:
725:
723:
718:
714:
710:
658:
646:
641:
611:
610:
607:
603:
602:
601:
600:
596:
592:
585:
584:
581:
577:
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572:
571:
570:
563:
559:
555:
551:
547:
534:
530:
526:
522:
518:
514:
510:
497:
494:
493:
492:O → 3Ca + SiO
491:
484:
481:
480:
475:
472:
471:
469:
464:
460:
450:
448:Hydration steps
435:
421:
407:
393:
379:
365:
326:
322:
318:
311:
300:
297:
296:
294:
284:
281:
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278:
268:
265:
264:
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215:
205:
201:
189:
177:
158:
154:
143:
139:
128:
101:
97:
82:
73:
69:
62:Portland cement
53:
49:
46:
42:
39:
35:
31:
21:
12:
11:
5:
1037:
1027:
1026:
1021:
1016:
1001:
1000:
971:ArchéoSciences
957:
930:
915:
895:
869:
861:
843:
828:
804:
802:
799:
798:
797:
791:
783:
780:
771:
768:
736:
731:
727:
721:
716:
712:
656:
644:
640:
637:
620:
619:
605:
594:
579:
575:
567:
566:
561:
557:
553:
549:
537:
536:
532:
528:
524:
520:
516:
512:
504:
503:
489:
462:
458:
449:
446:
440:
439:
436:
433:
430:
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425:
422:
419:
416:
412:
411:
408:
405:
402:
398:
397:
394:
391:
388:
384:
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380:
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370:
369:
366:
363:
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355:
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341:
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324:
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245:
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137:
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118:
114:
113:
110:
99:
81:
78:
71:
51:
44:
37:
33:
9:
6:
4:
3:
2:
1036:
1025:
1022:
1020:
1017:
1015:
1012:
1011:
1009:
990:
986:
981:
976:
972:
968:
961:
953:
949:
945:
941:
934:
926:
922:
918:
916:0-12-683900-X
912:
908:
907:
899:
883:
879:
873:
864:
862:2-912143-04-7
858:
854:
847:
839:
835:
831:
829:0-7277-2592-0
825:
821:
820:
812:
810:
805:
795:
792:
789:
786:
785:
779:
777:
767:
765:
761:
758:
754:
750:
746:
742:
741:calcium oxide
708:
704:
700:
696:
692:
688:
683:
681:
677:
674:
671:or contained
670:
666:
662:
654:
650:
636:
633:
629:
625:
614:
569:
568:
546:
545:
544:
542:
509:
508:
507:
468:
467:
466:
455:
445:
437:
431:
428:
427:
423:
417:
414:
413:
409:
403:
400:
399:
395:
389:
386:
385:
381:
375:
372:
371:
367:
361:
358:
357:
354:Rhombohedral
353:
350:
347:
346:
342:
336:
335:
332:
329:
316:
306:
292:
276:
260:
259:orthosilicate
256:
252:
207:
197:
196:
192:
185:
184:
180:
173:
172:
168:
165:
164:
160:
150:
149:
145:
135:
134:
130:
124:
123:
119:
116:
115:
107:
104:
95:
86:
77:
67:
63:
59:
29:
25:
19:
992:. Retrieved
970:
960:
943:
939:
933:
905:
898:
886:. Retrieved
881:
872:
852:
846:
818:
773:
699:wollastonite
694:
687:lime mortars
684:
682:impurities.
678:or a lot of
642:
628:interlocking
621:
552:S + 6H → C
538:
505:
451:
443:
330:
312:
213:
112:Mass %
91:
23:
22:
888:November 5,
878:"Hatrurite"
788:Cement kiln
757:Tournaisian
705:along with
613:portlandite
531:O + 3Ca(OH)
465:S surface.
396:Monoclinic
382:Monoclinic
368:Monoclinic
328:) and CaO.
1008:Categories
994:2010-07-21
882:mindat.org
760:limestones
438:Triclinic
424:Triclinic
410:Triclinic
337:Temp (°C)
309:Polymorphs
1014:Silicates
989:1960-1360
925:925061061
770:Detection
764:cathedral
745:lime kiln
703:rankinite
665:limestone
649:lime kiln
359:1060-1070
291:aluminate
66:Törnebohm
838:38207086
782:See also
661:medieval
632:strength
599:C-S-H +
527:·3H
373:990-1060
348:>1070
343:Crystal
43:3CaO·SiO
755:), the
753:Belgium
749:Tournai
743:in the
676:nodules
604:3Ca(OH)
488:+ O + H
429:<620
415:620-920
401:920-980
387:980-990
275:sulfate
255:calcium
251:clinker
1024:Cement
987:
923:
913:
859:
836:
826:
776:belite
724:S) or
454:belite
315:belite
109:Oxide
801:Notes
695:et al
673:chert
597:O →
586:alite
564:+ 3CH
501:+ 2OH
479:+ SiO
340:Name
131:25.2
120:71.6
24:Alite
985:ISSN
921:OCLC
911:ISBN
890:2020
857:ISBN
834:OCLC
824:ISBN
701:and
680:clay
543:as:
519:+ 6H
242:0.01
238:0.95
234:0.04
230:0.03
226:0.01
222:0.06
218:2.90
208:0.2
193:0.1
181:0.1
169:1.1
161:0.7
146:1.0
975:doi
948:doi
944:117
730:SiO
715:SiO
578:SiO
574:2Ca
515:SiO
511:2Ca
470:3Ca
323:SiO
295:AlO
263:SiO
166:MgO
125:SiO
117:CaO
98:SiO
56:in
36:SiO
1010::
983:.
969:.
942:.
919:.
880:.
832:.
808:^
778:.
735:(C
726:Ca
720:(C
711:Ca
593:6H
591:+
548:2C
495:4−
482:4−
319:Ca
298:5−
282:2−
279:SO
266:4−
236:Si
232:Al
228:Fe
224:Na
220:Mg
216:Ca
174:Na
151:Fe
136:Al
76:.
32:Ca
30:,
997:.
977::
954:.
950::
927:.
892:.
867:.
865:.
840:.
751:(
737:2
732:4
728:2
722:3
717:5
713:3
657:2
645:2
606:2
595:2
580:5
576:3
562:3
560:H
558:2
556:S
554:3
550:3
533:2
529:2
525:2
521:2
517:5
513:3
498:4
490:2
485:4
476:2
473:+
463:3
459:3
457:C
434:1
432:T
420:2
418:T
406:3
404:T
392:1
390:M
378:2
376:M
364:3
362:M
351:R
325:4
321:2
317:(
301:4
293:(
285:4
277:(
269:4
261:(
246:5
244:O
240:P
204:5
202:O
200:2
198:P
190:O
188:2
186:K
178:O
176:2
157:3
155:O
153:2
142:3
140:O
138:2
127:2
100:2
74:S
72:3
70:C
54:S
52:3
50:C
48:(
45:2
38:5
34:3
20:.
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