关于混凝土坝应力监测应变计组应变不平衡量调整

On the unbalanced strain adjustment for strain groups of concrete dam monitoring

坝体应力应变监测是高混凝土坝必设的重要监测项目。目前国内有关文献的应变计组的应变不平衡量处理存在不尽合理甚至错误的情况,这可能在混凝土应力计算中引入不必要的系统性偏差。本文明确指出应变计组的不平衡量调整与测绘学的条件平差数学上等价,并利用其算法来统一处理各向应变计组的不平衡量调整问题。与传统的公式相比,得到的应变计组的应变不平衡量调整公式,具有更严格的数学基础和更明确合理的物理意义,有助于提高混凝土应变监测的数据质量。

Stress and strain is among the mandatory and major monitoring items for high concrete dams in China.Currently there are some confusions and mistakes in prevailing publications about the unbalanced strain adjustment for strain groups,which might cause systematic biases in concrete stress computation.In this paper it is pointed out definitively that the unbalanced strain adjustment is mathematically equivalent to the condition adjustment used in surveying.The condition adjustment algorithm was adopted to deal with the unbalanced strain adjustment for strain groups with different numbers of strain gauges in a uniform way.The formulae thus obtained,compared with the traditional ones,are featured by a more rigorous mathematical foundation and clearer physical meanings,and are helpful to data quality assurance in concrete strain monitoring.