Abstract:

The lining surface of different parts of canal accepts different solar radiation and has different temperature. In line with the balanced relationship between the amount of solar radiation and net solar radiation, a simple and practical solar radiation model was established for the back analysis of canal lining’s surface temperature. By using MATLAB programming, the atmospheric temperature T 0 at different parts of the canal and the variation of ling temperature T s with time t was calculated taking shaded parts into consideration. The relation between concrete temperature rise at different parts and atmospheric temperature rise were compared. Calculation example revealed that: the variation of atmospheric temperature T 0 and the lining plate temperature T s respectively at canal bottom, shaded slope and sunny slope were in consistency; with the rise of atmospheric temperature, the lining surface temperature increased rapidly and exceeded the atmospheric temperature and reached the maximum. But the range of temperature change varied significantly: sunny slope presents a widest range of temperature rise, followed by canal bottom and shaded slope. The maximum temperature of lining surface came later than that of atmospheric temperature. This model not only conforms with reality and provides a simple and feasible method for the back analysis of lining surface temperature.

Key words: trapezoidal canal, concrete lining, solar radiation, MATLAB, net radiation