摘要
工程上广泛采用基于Winkler模型的层状地基反力系数法对桩土水平动力响应进行分析,该方法忽略了地基土剪切作用的影响,与工程实际有一定偏差。另外,对桩土的非线性相互作用和如扩底桩、楔形桩等变截面桩问题常用的传递矩阵法或中心差分法,计算过程较为繁琐。基于Pasternak地基模型和Adomian分解方法,提出一种考虑地基土剪切作用的桩土水平动力相互作用近似计算方法,该方法计算简便且结果精度较高,对变截面桩问题有很好的适用性;并基于该方法,对扩底桩水平动力响应问题和影响因素进行分析。结果指出,扩底半径和上部桩周土弹性模量对扩底桩水平动力响应影响较大,随着扩底半径的增加和桩周土弹性模量的增大,扩底桩水平振动位移幅值逐渐减小。另外,在较低频率的荷载激励下,应考虑土层对桩的剪切作用。
To analyze the horizontal dynamic responses of a pile considering the interaction between the pile and surrounding soil,the layered soil resistance coefficient method,which is based on the Winkler model,is widely used in engineering.Shear action of soil around piles is neglected in this method,which does not correspond with engineering practices.Also,application of the transfer matrix method or central difference method in resolving the dynamic response of variable cross-section piles,such as belled piles,wedge piles,etc.,has some challenges.This paper proposes an approximate calculation method for the horizontal dynamic response analysis of piles based on the Pasternak model and the Adomian decomposition method,in which shear actions of the soil around the pile were considered.The method has a simple solution procedure and is suitable for the problems of variable cross-section piles.Using this method,the horizontal dynamic response of the belled pile and influencing factors on this response were analyzed.Results indicated that the expansion radius and elastic modulus of the soil around the upper pile had an important impact on the horizontal dynamic response of the pile.In addition,the amplitude of the horizontal vibrational displacement of the pile gradually decreased with increasing radius of the expansion and elastic modulus of the soil around the upper pile.Also,the shear action of soil on the pile should be taken into account under low frequency load excitation.
作者
丁肇伟
宋春雨
陈龙珠
DING Zhaowei;SONG Chunyu;CHEN Longzhu(Department of Civil Engineering,Shanghai Jiaotong University,Shanghai 200240,China)
出处
《地震工程学报》
CSCD
北大核心
2019年第6期1587-1596,共10页
China Earthquake Engineering Journal
基金
国家自然科学基金资助项目(51678361)
