变电站中减饱和法液化地基处理的原理与方法
2021-04-27侍成鄢博陈俊杰
侍成 鄢博 陈俊杰



摘 要:地基液化会给建筑设施带来灾难性的影响,是岩土地震工程面临的主要问题之一。传统液化地基处理方法强夯法、挤密砂桩法、碎石桩和水泥土搅拌桩等在工程实践中存在成本较高且技术复杂的问题。新型的液化地基处理方法减饱和法,相对于传统液化地基处理方法具有成本低,简单易操作等诸多优势。从加固机理、减饱和的几种产气方法、产生气体的形态及稳定性等几方面对减饱和法进行介绍和分析,对变电站建设降低地基处理成本提供了技术支撑。
关键词:地基液化;砂土;减饱和法
中图分类号:TU473.1 文献标识码:A 文章编号:1001-5922(2021)07-0171-05
The Principle and Method of Liquefaction Foundation Treatment by Desaturation Method in Substations
Shi Cheng,Yan Bo,Chen Junjie
(Economic and Technical Research Institute of State Grid Jiangsu Electric Power Co., Ltd., Nanjing 210008,China)
Abstract:Foundation liquefaction will bring catastrophic effects on construction facilities, and it is one of the main problems in geotechnical seismic engineering. Traditional liquefied foundation treatment methods such as dynamic coMPaction method, coMPacted sand pile method, gravel pile and cement-soil mixing pile have high cost and complicated technology in engineering practice. The new type of liquefied foundation treatment method, the desaturation method, has many advantages, such as low cost, simple and easy operation, coMPared with the traditional liquefied foundation treatment method. Introduce and analyze the desaturation method from the aspects of reinforcement mechanism, several gas production methods for desaturation, the form and stability of the gas produced, and provide technical support for the construction of substations to reduce the cost of foundation treatment.
Key words: foundation liquefaction; sandy soil; desaturation method
0 引言
地震作為一种强烈的地质灾害,会带来巨大的灾难。大量的地震灾害调查表明,饱和土体液化导致的震陷和侧向扩展能够引起地上结构的不均匀沉降、倒塌、倾斜、道路开裂、地下结构上浮、破裂和其他形式的破坏等一系列严重的灾害[1-3]。近年来,诸多地震发生时,也都伴随有土体液化现象。例如,2011年的新西兰克赖斯特彻奇地震,2011年的日本东北地区大地震和2008年的汶川地震[4]。如今,在我国基础建设迅猛发展的新时期,如何有效处理地基液化问题是保证基础建设安全的关键问题之一。地基液化通常容易发生在松散的饱和砂土和粉土地基当中。由于其颗粒松散且处于饱和状态,在经受一定强度的地震荷载作用后,土体中的水不能及时排出,土中超静孔隙水压力不断上升,土颗粒间有效应力下降。……
