Several mechanics problems and related concepts in engineering design of anchored slide-resistant piles were analyzed and discussed. There are two mechanics models and corresponding calculation methods of embedding section of anchored slide-resistant piles

which were classfied into rigid pile model and elastic pile model according to the relative rigidity of pile-soil system. By means of mathematical operation of limit

the mechanics consistency of the two calculation methods was illustrated. That is

calculation results based on rigid pile model is just only a special case of elastic pile model. Comparition results of displacement and bending angle of embedding section between the two mechanics models showed that

by using elastic pile model is more safe for determining tensile loads of anchor cable than by using rigid pile model in design of anchored slide-resistant piles. The criterion of converted length of embedding section is 1.3 (“m method”) or 0.8 (“K method”)

for if calculating depth are less than them

the difference between two mechanics models are less than 5 %. Because the dip angle of pile’s anchor cable effect on horizontal restraining force and horizontal restraining rigidity as well

the optimal dip angle can give consideration to both diminish initial prestress loads of cable and decrease horizontal displacement of pile. The principle of bending moment equilibrating in engineering designs was conditional actually

because the target of making approximate equality of peak value of pile’s positive and negative bending moment extremely depends on sufficiently large tensile loads can be supplied by anchor cables and appropriate initial prestress loads were applied.