© Since the back of the wall is inclined and friction is assumed to develop along its face, there are vertical as well as horizontal components of thrust from the backfill and surcharge.

© The design vertical action due to surcharge and backfill is treated as unfavourable for both sliding and toppling, since it comes from the same sources (backfill and surcharge) - both of which provide unfavourable horizontal actions.

© Additional stabilizing moments are derived from the vertical thrusts from the backfill and surcharge.

© The eccentricity is outside of the middle third and would normally not be acceptable for a mass gravity wall, as it implies tension within the structure. Note that Eurocode 7 only requires the eccentricity to lie withing the middle two-thirds of the base and hence this design satisfies its requirements.

© Sliding governs the calculation for Design Approach 1, with Combination 2 being critical. The degree of utilization (57%) is relatively low, suggesting that the wall may be over-designed. However, water pressure may develop behind the wall which will reduce the degree of utilization.

© The results for Design Approaches 2 and 3 are presented in summary only. The full calculations are available from the book's website at

Design Approach 2 applies factors greater than 1.0 to actions and resistance. Sliding governs the design for DA2 with a degree of utilization (51%) that is slightly lower than for DA1 and well within the limits of Eurocode 7.

Design Approach 3 applies factors greater than 1.0 to structural actions (i.e. the self-weight of the concrete) and material properties. Once again, sliding governs with a degree of utilization (57%) identical to DA1.

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