Abstract:

The long sequence of tunnel ambient exterior luminance L20(S) and the traffic data of 6 highway tunnels in the coastal hilly area of Eastern Zhejiang are obtained by using the improved environmental sketch method combined with the loop coil vehicle detector, so as to learn the variation laws of highway tunnel dimming and further solve the problem of dimming control matching with lighting demand of highway tunnel. The results show that: (1) In the Eastern Zhejiang, Area the ratio among peak values of L20(S) in spring, summer, autumn and winter, are about 0.95, 1,0.95, 0.85 respectively; and that in sunny, cloudy, overcast and heavy overcast weather conditions are about 1, 0.6, 0.18, 0.11 respectively. (2) L20(S) is the main factor which affects the lighting demand of the highway tunnel in eastern Zhejiang, and its contribution to energy saving is more than 95%; the influence of traffic on the tunnel lighting is limited. (3) The shorter the tunnel is, the more significant the energy savings is achieved by the dimming control; the stepless dimming of the short tunnels can save energy consumption by more than 50%.

Key words: highway tunnel, lighting demand characteristics, dimming control, improved environmental sketch method, daily sequential variation of access zone luminance