| Traditional prestressed high-strength concrete pipe piles(PHC pipe piles)are delivered to the construction site for installation after prefabrication in the factory,which can greatly improve the construction efficiency,suitable for the rapid construction of pile foundations,and are widely used in domestic building structures.However,in order to meet the needs of on-site assembly and pile connection,the diameter of commercial PHC pile pipes should not be made too large,and the vertical and horizontal bearing capacity of a single pile are limited,making it difficult to apply to higher bearing requirements and more complicated construction conditions.Bridge engineering requirements.This paper presents a new prefabricated UHPC tubular pile without Prestressing Tendons and its construction method.Based on the ABAQUS finite element method,the bearing capacity of the new pipe pile is studied.The main contents and achievements are summarized as follow:(1)The Combined structure,mechanical characteristics,pile connection form and construction method of a new type of non-prestressed UHPC pipe pile foundation are described.The new UHPC pipe pile foundation proposed in this paper not only inherits the advantages of traditional PHC pipe piles such as good quality and fast construction,but also meets the needs of high bearing capacity of bridge engineering,which can provide a way of thinking for the design and construction of assembled foundations of bridge engineering.(2)The ABAQUS program was used to establish a three-dimensional finite element model of a single-section PHC pipe pile and a new UHPC pipe pile,to compare and analyze the bearing capacity of the two types of pipe piles,and to study the effects of different parameters on the axial compression and shear bearing capacity of UHPC pipe piles.law.The research results show that: the bearing capacity of the unprestressed UHPC pipe pile proposed in this paper is significantly improved;the axial bearing capacity of the UHPC pipe pile is positively correlated with the wall thickness,concrete strength,and coupling rate;the shear resistance of the UHPC pipe pile The bearing capacity has a positive correlation with wall thickness and hoop ratio,but has a negative correlation with the shear span ratio.(3)The ABAQUS program is used to establish the finite element analysis model of the assembled non-prestressed UHPC pipe pile.Through the pseudo-static simulation of the reciprocating load,the mechanical properties of the assembled UHPC pipe pile and the integrally cast UHPC pipe pile are compared and analyzed,Analyzed the influence of different parameters on the mechanical properties of assembled UHPC pipe piles.The research results show that: under the same conditions,the assembled UHPC pipe pile is slightly lower than the cast-in-place pipe pile,but its stiffness degradation rate is smaller than that of the cast-in-place pipe pile;Larger,the axial compression ratio and the strength of the pouring material have less effect on the ultimate force of the pipe pile. |
