摘要：Among the various physical external factors influencing the quality of concrete, the meteorological
ones play an extremely important part since they act not only when preparing the concrete, but also when
transporting and casting or putting it into forms. Out of all the meteorological factors, air-temperature exerts
the most powerful influence on the main features of concrete structures that may thus be affected both by low
(negative) and high air-temperatures. In the first case, low (negative) air-temperatures may substantially delay
the process of attachment and consolidation of concrete, and in the second case, high air-temperatures may
impede the moulding process, reduce the time of attachment and favour the rapid loss of water by intense
evaporation. In order to avoid the negative consequences of low air-temperatures, concrete must be prepared
and attached to various structures only after important measures of protection had been taken so as to severely
limit its heat losses and largely maintain, as long as possible, the heat radiated during hydration processes. On
the contrary, in case of high air-temperatures, one must take into account measures destined to largely
diminish the water losses during the evaporation processes, that may eventually lengthen the time of
attachment, thus ensuring better workable conditions.
关键词：air-temperature; concrete; preparing, transporting and attachment conditions.
