Transmission line in Sichuan mountainous area always layout in steep slope

where Gravel soil and bedrock dual structure formation are common in the region. As such

proportional coefficient m of ground horizontal resistance coefficient is the problems to be settled urgently in the design of transmission line tower pile foundation in the steep slope. m value is obtained by the static horizontal loading test of single pile. Three methods including field experiment

indoor model test

and numerical simulation are used to investigate the changing rules

influence factors and accessor methods of the m value. The results indicate m value of slope site decreases linearly with the increase of slope

and the decrease of m in gravel soil is greater than in the gravel soil-bedrock foundation. The most influencing factors on m value are ground slope

soil compactness

pile length and pile diameter. The proposed prediction formula considers impact factors of m value of the gravel soil

gravel soil and bedrock in slope site

and provides the correction coefficient.