中文摘要：

为量化既有线平面重构成果,建立以圆曲线半径,前后缓和曲线长为自变量,既有线上所有测点至重构线路拨距平方和为因变量的平面重构评价函数。考虑该函数为多元隐函数的特点,提出基于方向加速法优化求解评价函数极小值及其对应自变量的平面重构算法。并探讨优化求解过程中圆曲线半径,前、后缓和曲线长度初始值选取,规范中相关约束条件的引入问题。通过实例分析,证明该算法重构效果明显优于传统偏角法,完全满足工程实际要求。

英文摘要：

In order to quantify the reconstruction result, an evaluation function which has three arguments, i. e. circular curve radius and two transition curves＇ length was built. And its function value is the sum of squares of all distances from measuring points to reconstruction plane. Considering it is a ternary implicit function, a plane reconstruction algorithm that solves the minimal value of the function and corresponding three arguments by direction acceleration method was proposed. How to determine the arguments＇ initial values and import constraint conditions in design code in the process of iterative were also discussed. This algorithm has rigorous theory, simpie logic and can be applied easily. Examples analyses show its reconstruction result is obviously superior to the traditional deflection angles method and this algorithm is feasible for engineering practice.