The method of fragments is an approximate analytical procedure for computing groundwater flow. Principal assumptions used in the derivation of this method are: the flow is confined and of finite depth. Darcy's law is valid and, therefore, laminar flow exists. A steady state flow exists. The soil medium is homogeneous and isotropic. Equipotential lines at certain locations of the flow region can be approximated by vertical lines. This report documents CFRAG, a computer program for seepage analysis of confined groundwater flow by the method of fragments. The program provides the following information: (a) Flow per unit width through the specified soil medium. (b) Head loss per fragment. (c) Exit gradient. (d) The resultant uplift and lateral forces acting on the structure. and (e) A sketch of the structure with uplift and lateral pressure diagrams drawn appropriately. Data can be input by an interactive question-and-answer session, by a previously created data file, or by a pictorial menu using the crosshairs to select fragment types. The report presents example computer results with hand verification and example problems with comparisons made among the method of fragments, flownets, method of creep, and finite element analysis. It also presents a parametric study of a simple hydraulic structure to illustrate the effect on the solutions obtained by the various methods when the geometry of the structure is altered. Keywords include: uplift pressures.The method of fragments is an approximate analytical procedure for computing groundwater flow.
|Title||:||Computer-Aided Structural Engineering (CASE) Project. Seepage Analysis of Confined Flow Problems by the Method of Fragments (CFRAG).|
|Author||:||M. E. Pace, R. Mosher, D. R. Williams, T. F. Wolff, ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS.|