The first and basic cause of the failure of concrete is repeated freezing (thawing) of moisture contained in the pores, microcracks, and cavities of the concrete. On transition to ice, water existing in the free state in cracks increases in volume, expanding the recess in which freezing occurs. A reduction in strength below the initial value is to be expected and further cycle of freezing and t...

The present study examines the effects of historic climate variability on cold-season processes, including soil temperature, frost depth, and the number of frost days and freeze–thaw cycles. Considering the importance of spatial and temporal variability in cold-season processes, the study was conducted in the midwestern United States using both observations and model simulations. Model simulati...

the purpose of this study is estimate waiting time of frost occurrence over iran. the daily data from 663 synoptic and climatology over iran during 1/1/1340 to 11/10/1383 have been used. data interpolated by kriging method on 15ã—15 km pixels. the data base with dimension 15992ã—7187 obtained that on the rows were days and on the column were pixels. by t student test the interval mean of waitin...

Damage is an important quality factor for grading, marketing, and end use of soybean. Seed damage can be caused by weather, fungi, insects, artificial drying, and by mechanical damage during harvest, transportation, storage, and handling. The current visual method for identifying damaged soybean seeds is based on discoloration and is subjective. The objective of this research was to classify so...

Stem tissues of red-osier dogwood (Cornus stolonifera Michx.) acclimated from -3 C to -40 or -50 C in 8 to 10 weeks under a short photoperiod (9 hours) and controlled temperature conditions. During the summer months plants did not acclimate as well as at other times. The sequence of day/night temperature regimes which induced maximum acclimation was 20/15 C for 5 to 6 weeks; 15/5 C for 2 to 3 w...