Ageing treatment measures of filling material forexpansion joint of reinforced concrete box culvert

After the aging and cracking of reinforced concrete box culverts in dykes, seepage and leakage will occur from these culverts in high water periods, resulting in dangerous conditions and posing serious threats to the dyke safety. There are many reinforced concrete box culverts in the Yangtze dykes, and seepage and leakage phenomena arise from the contraction joints of some culverts. This paper presents two methods to treat the cracking of culvert contraction joints, i.e. establishing a rubber strip with clip plate or patching the old water stop strip. The water-stopping effect of the first method is good, but its cost is high, and this method has high technologic requirements and is adapted only to culverts having stable foundations and no remaining settlements. For the second method, the late placed concrete is likely to be split from the old concrete and its water-stopping performance is not as good as that of the first method, but it has advantages of low cost and being convenient for construction. The two methods have been applied to the treatment of several dozens of old culverts, achieving good results.