Coefficient of Friction between Directly Buried Hot-Water Heating Pipe and Soil

Bearing large temperature variation on the steel pipe, directly buried hot-water heating pipe will bear great thermal stress when the pipe-soil interaction is strong enough, which is harmful to the service life of heating pipelines. The performance of the friction between pipe and its surrounding soil plays an important role in the district heating for the safety and economy. To obtain the performance of friction between pipe and soil during the operating period, a test system was established based on wireless transfer technology for the in-situ long-time measurement. The results show that the friction variation during temperature-rise process differs from that during temperature-drop process. This investigation studies the variation of friction coefficient with temperature by in-situ measurement.