The torsion problem of aperture ring heavy-section bars was studied.

Normal section strength calculation for reinforced concrete flexural member with ring section

For partial prestressed concrete high-rise tower structure with ring section,in order to meet regular service,the higher prestress degree usually is applied.

Starting with the basic assumption while calculating the bearing capacity of the reinforced concrete normal section,the function expression is set up for different stress graphs on the ring section.

And the reinforcement design method for structures with annular section was elaborated.

Qualitative comparison between slide-resistant pile and other laterally loaded piles are made in terms of loading characteristics,simplicity for calculation and requirement for reinforcement distribution,and improvement is made to the computation method for the non-uniform distribution of reinforcement of slide-resistant piles with round or annular section.

The unified equations and graphs on the general failure expression were presented through the study of reinforced concrete elements with annular section.