某住宅楼倾斜原因及相关规范问题的讨论

The reasons why a house inclined and discussions on some related questions of the code

分析了导致其倾斜的主要原因:①设计中对在高压缩湿陷性黄土地基上进行大面积填土认识不足;②忽视了周边环境的影响及工程活动对环境改变所产生的反作用;③勘察时将新近堆积黄土误判为一般风成湿陷性黄土。指出了在这一地区进行工程设计时容易忽视的问题:只盯着可能会发生的湿陷变形而忽视了必然要发生的压缩变形。对相关的两个规范问题进行了讨论:①通过理论分析和试验验证了在室内湿陷试验中采用固定浸水压力的不合理性;②对计算湿陷量公式中系数β和β0的合理性提出了质疑,并给出了修改建议,有助于澄清对于湿陷系数和计算湿陷量的模糊认识。

There are three main reasons that caused the house inclined：① The designer had a wrong understanding about the result of a large area fill on the highly compressible foundation of collapsible loess.② The effects of circumstances around the house and the reaction of its change caused by constructions were neglected.③ The investigator gave a wrong judgment on neo-loess as Q3eol ones.A problem that is often neglected by some designers in collapsible loess regions is pointed out.That is they always put all of their attention to the collapsible settlement which could only take place when its foundation is wetted.But the compression settlement which is inevitable is neglected in their design.Two related questions of the code are discussed：① Un-rationalization of fixed loading in immersion test was verified by theory analysis and test data.② The rationalization of coefficient β and β0 in collapse settlement estimation according to the code was doubted.At last some suggestions are advanced.They are favorable to clear up the misunderstanding about collapsible coefficient and collapsible settlement for some engineers worked here.