碎石料干湿循环变形试验及计算方法

Study on experiment and calculation method of dry-wet cycle characteristics of rockfills

摘要:

为深入研究山区机场高填方中常用碎石料的流变及干湿循环变形特性,利用特制的大型侧限固结仪对其进行室内试验.结果表明:同等应力水平下碎石料在干湿循环作用下的变形比常规流变变形的后期增长趋势更为明显,其特点是在每次干湿循环中只是浸水初期变形增长较快,待排干水后变形趋于平缓;经分析干湿循环变形值与循环次数的对数之间有较明显的线性关系.另外,根据试验成果提出了考虑当地降雨情况的常规流变变形和干湿循环变形的简化耦合计算方法,并结合当地降雨规律对云南X机场填方体进行了工后沉降变形计算.

Abstract:

With the specially designed large-scale oedometer,routine rheological tests and dry-wet cycle tests have been conducted on specimens to investigate the rheological and dry-wet cycle characteristics of rockfills,which have been widely used in the high-fill foundations of mountain airport.The test results demonstrate that the long term deformation due to dry-wet cycle grows more evidently than the routine rheological deformation,which increases rapidly during early immersion,and gradually flattens after draining the water.There is approximately a logarithmic relationship between dry-wet cycle deformation and cycle numbers.In addition,a simplified coupling calculation method that can meanwhile compute the rheological deformation and dry-wet cycle deformation is proposed,by which the settlement of foundation after construction in X airport of Yunnan Province is computed according to local rainfall law.