How can resistance to sliding in retaining wall design be increased?

Increasing the weight of the wall enhances resistance to sliding primarily because it increases the vertical load acting on the base of the retaining wall. This additional weight enhances the component of the wall's weight that resists lateral soil pressure and the driving forces acting on the wall.

When the weight of a retaining wall increases, the resistive forces at the base also increase due to the higher normal force acting perpendicular to the base surface. This contribution to resistance against sliding becomes critical in ensuring stability, especially in situations where the lateral earth pressure and hydrostatic forces are considerable.

Furthermore, heavier walls are less likely to be displaced by sliding forces, offering an added level of safety in design against failure due to sliding. Utilizing additional materials, such as using heavier concrete or incorporating dead weight, can significantly improve this aspect of retaining wall design.

In contrast, reducing soil weight or decreasing friction force would reduce the wall's overall stability, while increasing the wall's height could potentially increase pressures without providing proportional resistance, depending on the design configuration and conditions.