Page 72 - 2022年第53卷第1期

Experimental study on leakage detection of earth rockfill dams
using passive infrared thermography

1，2 1，2 1，2 1，2 1，2
ZHOU Renlian ，SU Huaizhi ，LIU Mingkai ，XU Lang ，HUA Qianyu
（1. State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering，Hohai University，Nanjing 210098，China；
2. College of Water Conservancy and Hydropower Engineering，Hohai University，Nanjing 210098，China）

Abstract：At present，manual patrol is still the main means to inspect leakage dangers of the embankment
in flood season，which seriously restricts the level of emergency disposal. To explore the feasibility of pas⁃
sive infrared thermography sensing earth rock dam leakage under natural environmental conditions，an earth
dam leakage model test platform which can fully simulate the real service conditions of earth rock dam and
river embankment in flood season is built. The test results show that afternoon and night are the better
time to detect the leakage of earth rockfill dams by infrared thermography. The leakage outlet usually shows
low temperature anomaly in the afternoon and high temperature anomaly during night. The concentrated leak⁃
age affected zone has obvious trailing contour characteristics and temperature gradient variation characteris⁃
tics centered on the leakage outlet on the thermal image. Whether the downstream dam slope is covered
with turf or not，it is feasible to detect the leakage of earth rockfill dams by passive infrared thermography
under natural environmental conditions.
Keywords：earth rock dam；embankment；leakage；infrared thermography；thermal image
（责任编辑：李 娜）

（上接第 53 页）
Discussion on water and sediment dynamic characteristics and layout optimization of typical
artificial reefs in Liaodong Bay of Bohai Sea

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SHU Anping ，QIN Jiping ，SUN Tao ，YANG Wei ，WANG Mengyao ，ZHU Jiapin
（1. KeyLab of Water and Sediment Sciences of MOE，Beijing Normal University，Beijing 100875，China；
2. Environmental Planning Research Center，Yunnan Research Academy of Eco-environmental Sciences，Kunming 650034，China；
3. Beijing Water Resources Dispatching Center，Beijing 100038，China）

Abstract：Artificial reef is an effective measure to improve the marine ecological environment and increase
fishery production. Different scale artificial reefs will produce different flow field effects. In this paper， 20
flume experiments were carried out to simulate the effect of the disposal spacing on the flow field of
square ecological reef unit reef in Juehua Island， Liaodong Bay， using PIV technology. The results show
that with the increase of velocity，the height，length，area and other eigenvalues of upwelling and back vor⁃
tex show an increasing trend，while the turbulence intensity shows a decreasing trend. At the same veloci⁃
ty，the eigenvalues of upwelling and turbulence intensity do not change with the spacing，but the eigenval⁃
ues of back vortex first increases and then decreases with the spacing increasing. On the other hand， the
entropy method is used to evaluate the flow field effect under the four spacings based on the hydrodynamic
characteristics and economic cost index. When only considering the hydrodynamic index， the comprehensive
score of flow field effect from large to small is 1.25L>1.00L>0.75L>1.50L， and the gap between 1.25L and
1.00L is very small； after the cost index is included， the comprehensive score is 1.25L>1.00L>1.50L>
0.75L. Moreover, the score diffrence between 1.25L and 1.00L is very small, and it reaches a relative maxi⁃
mum at 1.15L through meticulous simulation. According to the experimental results，from the perspective of
theory and practice， considering the ecological benefits and economic costs， it is suggested that the origi⁃
nal design spacing should be increased by 15% when the square unit reef is put into practice，which pro⁃
vides a reference for the construction of artificial reef.
Keywords： artificial reef； flow field effect； turbulence and sediment incipient-suspension； disposal spac⁃
ing；entropy method
（责任编辑：李福田）

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