Recently, a simple new approach -force balance method (FBM) -and its improved version have been proposed to calculate geometric correction factors [1][2][3][4]. In the initial FBM, the stress distribution in front of the crack tip along the crack line for a finite-width plate was assumed to have the same form as that in the corresponding infinite plate, modified by a geometric correction factor. In the improved version, the stress distribution ahead of the crack tip along the crack line for a finite-width was assumed to have a similar form to that in the corresponding infinite plate, modified by adding a geometric correction factor to the singular term only [1,2]. By means of the assumed stress distributions and the principle of force equilibrium, one can easily derive the geometric correction factors which were found to be in good agreement with the results reported in the literature. However, there is an argument that the above-mentioned assumptions do not seem very convincing, although the assumption of the initial FBM was numerically assessed by means of finite element method for the cases of the standard CCT specimen loaded by the remotely applied stress and a pair of tensile forces on the center of the specimen [5,6], and the results showed that the assumption is basically applicable. For the center cracked finite specimer subjected to a segment uniform pressure acting over an arbitrary part of the crack, the validity of the assumptions has been assessed. Therefore, in this report both types of assumptions concerning the stress distribution ahead of the crack tip are evaluated by means of a weight function method (WFM) for the center of a cracked finite strip loaded by a segment uniform pressure acting on an arbitrary part of the crack. The SIF solutions obtained by different methods for this loaded crack geometry are compared. Finally, based on the results obtained from the WFM, the basic assumptions and the accuracy of FBM are discussed.