Prediction of Moisture Movement in Expansive Clays

摘要

The report describes two computer programs for determining changing moisture distribution with time. Program FLOPIP1 is arranged to work one-dimensional problems and computer Program GCHPIP1 solves moisture distribution problems in two dimensions. The equation governing the flow of moisture is a concentration-dependent, parabolic, partial differential equation which is solved numerically using the implicit Crank-Nicholson method of marching forward in time. Example problems are worked to demonstrate the capabilities and breadth of application of the computer programs and to prove the validity of the approach. The one-dimensional example problems are concerned with matching measured field data and with presenting the results of a parameter study of various suction and permeability factors. The field data can be duplicated to within very close tolerances. The two-dimensional example problems are arranged to demonstrate the versatility of computer Program GCHPIP1. Problems solved include a two-dimensional consolidation problem, ponding problems, and a problem of predicting moisture distribution within a concrete highway bridge girder. (BPR Abstract).