高频振锤薄壁板墙技术处理砂砾石堤基试验研究

Experimental study of high-frequency vibratory hammer sheet wall technology of dealing with sand-gravel levee foundation

高频振锤薄壁板墙技术在砂层堤基的垂直防渗施工中得到了广泛应用。为探索一种适用于洞庭湖区砂砾石堤基的垂直防渗施工方法,对高频振锤薄壁板墙技术的施工工艺、流程等进行了一些改进,实现了施工全过程的计算机控制。将改进后的工法应用到周家湾堤段试验工程中,并采用围井检测、钻孔取芯、测压管监测等手段检验了超薄防渗墙的成墙效果。结果表明,改进后的高频振锤薄壁板墙技术具有成墙连续、完整,防渗效果好、工效高、造价低等特点,是一种适用于处理砂砾石堤基的垂直防渗技术,可用于处理洞庭湖区及其他具有类似地质特征的堤防防渗工程。

High-frequency vibratory hammer sheet wall technology is widely applied to sand levee foundation in vertical cutoff wall construction. To explore a construction method of vertical cutoff wall dealing with sand-gravel levee foundation in Dongting Lake areas,some improvements of this technology including construction techniques and flow chart are made,and computer control in the course of construction is realized,then this method is applied to Zhoujiawan project. And some detections including enclosed well test,coring bit and piezometric tube are used to verify the effect of thin cutoff wall. Experimental studies indicate that improved high-frequency vibratory hammer sheet wall technology has the advantages over traditional grouting technology,such as continuum,integrity in forming wall,good anti-seepage effect,high construction efficiency and low costs,and it is an effective kind of vertical cutoff wall technology applied to sand-gravel levee foundation,it can be used to treat with the levee project in Dongting Lake areas and any other region with the same geological features.