关于《建筑工程抗浮技术标准》的理解与思考

Understanding and Thinking about “Technical Standard for Building Engineering against Uplift”

针对行业标准《建筑工程抗浮技术标准》JGJ 476—2019中的一些问题提出理解与思考。对于抗浮设计等级为甲级的工程,该标准增加了较多的工作内容,使用期内的地下水位预测是一个难点,开展基础数据积累和建立地下水数值分析模型是一种可行的方式,该标准将抗浮设计等级与基础设计等级挂钩并不完全合适。除整体抗浮稳定验算外,尚需对地下结构薄弱环节进行“单元抗浮稳定验算”,并与底板强度和变形验算结合考虑。在承压条件下,地下室底板大部分区域的水头值与承压水水头值相同。抗浮锚杆筋体的截面计算公式存在概念不清晰的问题。采用主动抗浮方法时,应充分考虑地层、环境的适应性,对排水盲沟的保土防淤、渗流计算及截水帷幕的耐久性问题应进行更深入的研究。

In view of some problems in the industrial standard " Technical standard for building engineering against uplift(JGJ 476—2019)", this paper presents understanding and thinking. For projects with anti-uplifting design grade A, this standard adds a lot of work content, among which the prediction of underground water level in the service period is a difficulty. The accumulation of basic data and the establishment of groundwater numerical analysis model are feasible approaches. It is not entirely appropriate for the standard to link the anti-uplifting design grade with the foundation design grade. In addition to the overall anti-uplifting stability checking calculation, the "unit anti-uplift stability checking calculation " for the weak parts of the underground structures should also be carried out, which should be considered in combination with the strength and deformation check of the floor. Under the condition of artesian water, the hydraulic head value of most areas of basement floor is the same as that of artesian water. The concept of cross section calculation formula of anti-uplifting bolt reinforcement is not clear. When adopting the active anti-uplifting method, the adaptability of stratum and environment should be fully considered. The problems of soil retention and clogging performance, seepage calculation of the drainage blind ditch and the durability of cutoff wall should be studied more deeply.