Mechanical Properties Of Double-row Piles Supporting Structure In Loess Slope Of Yan'an

The city of Yan'an, is located in the hilly loess plateau region, while the long and narrow watercourse makes lots of trouble in the process of city construction. Because the construction land is becoming increasingly scare, the city construction is intended to the slope on the both side of watercourse, so the security of slope engineering is getting more and more concern.Double-row piles supporting structure, as a kind of engineering measure, has been used wildly in slope reinforcement engineering and treatment of landslide geological disasters. However, the current research and application of double-row piles supporting structure is mostly concentrated in the coastal and southern regions, while less in the northwest loess region. For these reasons, the thesis is mainly discussed about the double-row piles supporting structure's work mechanism and pile-soil contact interactions in loess region, for the similar projects calculation to provide some reference.Firstly, it is sorted out the current domestic double-row piles on the calculation of several common methods, analyzed each method's characteristic and proposed the hand-count method calculating example in this thesis. The hand-count method is chosen the advanced correction factor method, combining with the pile-soil interactions factor and the Rankine active and passive earth pressure's distribution of the form, which of the concept is clear, simple and easy to guarantee accuracy.Secondly, the calculating model of double-row piles is given by the finite element program Marc. Some double-row piles correlative parameters, like the spacing of rows-pile,cross-section size,the height of joining beam and so on, are analyzed; In addition, on the role of pile-soil interaction, such as the critical contact depth, pile-side earth pressure and the distribution of frictional resistance are analyzed and obtained some reasonable spacing of rows, pile cross-section size and other related and reasonable conclusions.Finally, combined the relevant data of Yanan Ma Jiawan District 1 # eastern section of double-row piles supporting structure, the finite element calculating model is given and analyzed. Then, finite element analysis results with hand-count results are compared to prove the hand-count method proposed in this thesis for the loess region calculation of double-row piles is feasible, for similar projects to provide some reference.