高压注浆法在提高地基剪切波速中的应用

《核电厂抗震设计规范》要求核电厂核安全抗震物项宜坐落在基岩或剪切波速大于400 m/s的地基上，当地基剪切波速小于400 m/s时，需要对其进行换填素混凝土或者加固处理，以满足设计要求。文中通过对台山核电废液储存罐厂房地基处理方案的介绍，从经济和技术两个方面对比分析了开挖换填素混凝土和高压注浆法的优缺点。通过现场实践证明，对于深厚回填土，砂石含量较高时，采用高压注浆法可以将地基的剪切波速提高至400 m/s以上，避免了换填素混凝土时边坡的开挖和支护，施工安全风险小，造价相对较低。高压注浆法特别适用于以提高地基剪切波速为主要目的的深厚回填土的处理。

Application of High-pressure Grouting Foundation Treatment Based on Increasing Shear Velocity in Taishan Nuclear Power Plant

To meet nuclear safety criteria and have an anti-seismic function, buildings in a nuclear power plant should locate on bed rocks or rocks with a shear wave velocity greater than 400m/s. Foundation treatment is needed if the rock does not meet the above condition. Through an introduction on the foundation treatment of the liquid waste hold up tanks building in Taishan Nuclear Power Plant, comparison and analysis on the advantages and disadvantages of two methods are made in this article, namely excavation and backfill by plain concrete method and jet-grouting method. Practice has proven that under certain condition, jet-grouting method could efficiently increase the shear wave velocity. By adopting this method, slope excavation and retaining can be avoided, thus with a smaller constructive safety risk and a relatively lower cost. This method is fully fit for foundation with thick backfilled soil layer.