Abstract
This paper presents the regression analysis of the bearing capacity of a square footing on
reinforced pond ash. A power model has been developed to estimate bearing capacity of a
square footing ðqrsÞ on reinforced pond ash at any settlement using all possible regression
techniques based on 2088 model test data to select the significant subset of the predictors.
From the regression analysis, the predictors viz., the bearing capacity of a square footing ðqsÞ
at the same settlement on unreinforced pond ash, settlement to width of the footing ratio ðs=BÞ
in percentage, number of layers (N) of reinforcement, friction ratio (f), i.e. the ratio of the
pond ash—geotextile interface friction angle (c) to the direct shear friction angle of pond ash
ðfdÞ; depth of the upper most layer of reinforcement from the base of the footing to width of
the footing ratio ðu=BÞ; length of reinforcement sheet to width of footing ratio ðLs=BÞ and
vertical spacing of the reinforcement to width of the footing ratio ðSv=BÞ are found to be
significant to the model. The adjusted coefficient of determination ðR2
adjÞ for the proposed
model is found to be 0.9448 and for the regression model 72% data out of 2088 observed data
have prediction with less than 15% error. The additional set of 99 data was used for validation
of the model.
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