Summary Report of Experimental Study on Dehydration Crack Appearing in the Construction of Turpan Civil Airport Cement Concrete Pavement - The Issues and Discussion of Modern Concrete Science - page 248

Fig. 16.25 Map crack
emerged after galling (adding
ber)

Fig. 16.26 Map crack
emerged after utilizing
troweling machine

Map crack which emerged after galling (adding fiber) is shown in Fig. 16.25 .

Map crack which emerged after utilizing troweling machine (adding fiber) is

shown in Fig. 16.26 .
Conclusions on map crack in the experiment were as follows. Map crack usually
emerged one week after ending of curing at other airports, while serious map
dehydration crack emerged massively in this experiment before watering curing on
the second day of concrete molding. It was resulted in by local special climatic
conditions.
In the past, we thought that main causes for map crack are as follows: effect

①

of wind speed; effect of high temperature; effect of drying; effect of W/C;

② ③ ④

effect of mortar thickness
on concrete surface. Among these reasons, cause of cement itself was regarded as
secondary reason in the past by us. Yet in this experiment, no matter adding

effect of admixture; effect of cement itself; and

⑤ ⑥ ⑦

ber