Comparison of shallow foundation design using Eurocode 7 and Polish Standard

Abstract

Bearing capacity of cohesive soils was calculated based on PN-B-03020:1981P and Eurocode 7. Strength parameters of cohesive soil modified by the authors: shear strength in undrained conditions c u , effective cohesion c' and effective friction angle φ' were adopted for calculations acc. to Eurocode 7. Values of these parameters depend on a leading parameter -liquidity index I L .Bearing capacity was calculated for two pad foundations of a size B × L = 2.0 × 3.0 m and 1.5 × 2.0 m and for one 2.0 × 14.0 m strip foundation. The capacity calculated acc. to EC 7 was reduced by multiplying by a factor α = 0.87 to account for different bearing capacity coefficients in Polish Norms and Eurocodes. Performed calculations showed comparable bearing capacity of substratum irrespective of adopted norms EC 7 and PN for foundation pads. In all analysed cases, however, the bearing capacity of foundation strips calculated acc. to Eurocode 7 was higher than those calculated acc. to PN-B-03020:1981P. The reason is in the values and ways of accounting partial security coefficients and in differences in the values of shape coefficients used in the equation for ultimate bearing resistance of soil substratum.

On The Optimal Forms Finding of Shallow Foundations Made Up of Four Foothills with Explicit Considerations of Structural Perturbations

“…In geotechnical structure the analysis of dimensioning and tolerances were developed by Hillyard and Braid (1978) and other workers as Light and Gossard (1983) had applied new methods to modify a part of geometry. The researcher Olchawa and Zawalski (2014) had found that certain values of coefficients obtained by using Eurocode 7 are higher than those prescribed in the design of shallow foundations. In accordance with the structural tolerance, some specific errors of dimensioning were detected by Zong and Mao (2015) through analysis and mathematical modeling.…”