Overturning of concrete poles are occurred annually due to natural disaster such as a typhoon. The present code for the resisting moment and the safety on overturning of concrete poles in inclined ground is inadequate. In this study, the concept of the code for those in flat ground is applied to calculate the resisting moment in inclined ground using general analysis program L-Pile Plus13.8. According to the analytical results, the resisting moment in inclined ground is rapidly decrease as increasing the slope angle although the embedded depth are added by the additional embedded depth on the code. It is revealed that the capacity in inclined ground is equivalent to that in flat ground if additional embedded depth is increased from 1.5 to 3 times.

The welded connection is known as an essential factor for establishing qualified construction and/or maintenance of wrapped steel pipe. In this study, welded connection conditions in the coated pipes with large diameter (over 700 mm) in Korea water distribution systems were estimated for suggesting technically and economically available welded connection method. For the study analysis, current steel pipe usage and accident cases were investigated. In addition, the characteristics of each welded connection method and automatic or manual connection techniques were also compared and estimated. As results, automatic welded connection method is superior than manual welded connection method in aspect of pure construction cost (average 9%) or pure welded connection cost (average 13.5%). When the poor welding-working situations in Korea are considered such as high tolerance of out-of-roundness in KS regulation, a number of lap joint welded connections, the real cost benefits of automatic welded connection should be much higher than those of manual welded connections.