改进的最小二乘法计算固结系数

Improved Least Square Method for the Consolidation Coefficient Evaluation

目前计算固结系数常用的方法是时间对数法和平方根法,这两种方法属于作图法,同时这两种方法仅利用了试样固结试验中沉降量与时间关系曲线中较少的数据,人为因素影响较大,确定固结系数有一定误差,因此,如果利用固结过程中的实测数据直接求出固结系数将会是一种较好的计算方式。针对这种情况,采用工程上通用的最小二乘法,通过公式推导,改进边界条件,得出了实测数据与固结系数的关系公式,并用Matlab编程得到了固结系数的求解过程,由于采用计算机运算,从而避免了对固结初始值的依赖,减少人为因素的影响。计算结果表明,计算公式计算效果良好,有效的减少了计算中的误差。

At present, the logarithm of time and the square root of time methods are usually used to compute consolidation coefficient, from which only a few data were adopted for the consolidation coefficient. At the same time, the two solutions depend on the initial value from the curves and influenced the exactitude of consolidation coefficient directly. So, in this paper, an improved least square method is supposed to compute the consolidation coefficient with testing data. According to the derived formulae, a program is used to compute consolidation coefficient based on Matlab language and to eliminate human error. The computation results show a good effect and give a reduction of errors.