水泥混凝土板水分迁移模型的近似解析解

Approximate Analytical Solution of Water Movement in Concrete Slabs

摘要:

为了研究早龄期混凝土板的水分迁移规律，建立了早龄期混凝土路面板在外部干燥条件下的1维水分迁移模型，推导了基于Adomian分解法的求解任意边界条件下的非线性水分迁移模型的初边值问题的近似解析解，并与早龄期混凝土板的干燥过程试验数据和Crank Nicolson有限差分法数值解的结果进行了比较.结果表明，Adomian分解法的收敛速度非常快，是一种有效的求解任意边界、初始和扩散系数下的混凝土板干燥过程的偏微分方程的方法.

关键词:道路工程; 水泥混凝土路面; 水分迁移机理; Adomian分解法

Abstract:

In order to study the development of moisture insider concrete slabs, a one dimension water movement model for early age concrete slabs subjected to external drying was established. Adomian decomposition method (ADM) as an approximate analytical solution to initial boundary value problem (IBVP) of water movement equation for moisture distributions in early age concrete slabs with arbitrary boundary conditions was derived. Comparison between numerical results by Crank Nicolson finite difference scheme and experimental results suggests that the proposed ADM based approximate analytical solution approach converges very fast and is effective for solving nonlinear diffusion equation with arbitrary boundary and initial conditions as well as any diffusivity coefficient function for external drying of concrete slabs.

Key words:road engineering; Portland cement concrete (PCC) pavement; water movement mechanism; Adomian decomposition method