2009年,在小湾拱坝的安全监测中首次发现,部分无应力计的工作性态出现异常, 其测值反映的不全是坝体的自由变形,从而严重影响了应变观测成果的可靠性。针对无应力计的异常测值,从研究自生体积变形变化规律着手,结合统计分析方法,提出了判别异常数据的依据、标准和方法,建立了无应力计异常测值的修正方法,并对二滩拱坝部分无应力计观测成果进行了鉴别和修正处理。研究表明,提出的修正方法是有效的,修正后的成果反映了二滩坝体的实际应变。

Recently, some deformation measured by non-stress meters are found abnormal, which affects the reliability of observation results of strain meters. In view of this, we propose the basis, criteria and methods to distinguish abnormal data by researching the regularity of autogenous volumetric deformation of concrete. We also suggest some methods to correct the abnormal data of non-stress meters, and applied them to the discrimination and modification of non-stress meter results for Ertan arch dam. The results prove that the modification methods are effective, and the corrected results reflect the actual stress of Ertan dam.