桩网结构动力响应研究新进展

New research progress in dynamic response of pile net structure

桩网结构是近些年来出现加固软弱地基加固的路基,利用桩、路基、填土和土工材料之间相互协同作用,共同承担路基的上部荷载,提高结构承载力,具有土体侧向位移小、工后沉降易控制、地基处理厚度深、相邻建筑影响小等优点,故研究桩承结构路基在列车动荷载作用下的沉降变形特性和动力响应是十分必要的,桩承结构路基动力学已成为铁道工程、结构力学等众多领域的共同研究热点。首先简述了桩承结构的加固路基的机理;其次,分别从湿陷性黄土路基桩承结构的沉降计算、土拱效应和动力响应特性等方面进行理论研究与试验分析;并列举了采取桩承结构处理路基的工程实例,证明了其应用的可行性;最后指出其有待深入研究的问题,并展望高速铁路桩承结构发展的前景。

Pile net structure is a new type of weak foundation reinforcement technology that has emerged in recent years.It uses the synergy between piles,foundations,roadbed fills and geotechnical materials to share the upper load of the bearing subgrade and improve the structural bearing capacity.It has the advantages of small displacement,easy control after settlement,deep depth of foundation treatment,and small influence of adjacent buildings.Therefore,it is necessary to study the settlement deformation characteristics and dynamic response of the pile-supported subgrade under the dynamic load of the train.The subgrade dynamics of the pile-supported structure has become a hot topic of research in many fields such as railway engineering and structural mechanics.Firstly,the mechanism of the reinforced roadbed of the pile-supporting structure is briefly described.Secondly,theoretical research and experimental analysis are carried out on the settlement calculation,soil arching effect and dynamic response characteristics of the pile-stayed structure of the collapsible loess roadbed.The engineering example of the structure to deal with the subgrade proves the feasibility of its application.Finally,problems that need to be studied in depth have been pointed out,and proposes the prospect of the development of the high-speed railway pile-support structure has been proposed.