Rupture:
A mechanically stabilized earth (MSE) wall can fail due to rupture. Rupture occurs when the reinforcing elements embedded within the soil mass or facing material fail to resist the applied loads. This failure mode is often observed when the tensile strength of the reinforcement is exceeded, causing the soil to separate and the wall to collapse.

Bearing Failure:
Bearing failure can also lead to the failure of a mechanically stabilized earth wall. This occurs when the foundation soil beneath the wall is unable to support the applied loads, resulting in excessive settlement or deformation. Bearing failure can be caused by inadequate soil strength, insufficient compaction, or excessive loading.

Toppling:
Another mode of failure for an MSE wall is toppling. Toppling failure occurs when the wall rotates about its base, resulting in the overturning of the wall. This failure mode is typically observed when the lateral pressure exerted by the retained soil exceeds the resistance provided by the weight and geometry of the wall.

All of the above:
It is important to note that a mechanically stabilized earth wall can experience a combination of the aforementioned failure modes. The actual failure mode or modes observed depend on various factors such as the design of the wall, the properties of the soil and reinforcement materials, and the magnitude and direction of the applied loads.

For example, a poorly designed or constructed MSE wall with inadequate reinforcement may experience rupture failure when subjected to excessive lateral loads. Similarly, if the foundation soil beneath the wall is weak or poorly compacted, bearing failure may occur in addition to or instead of rupture failure. Additionally, if the wall is subjected to uneven or inclined loading, toppling failure may also be observed.

In summary, a mechanically stabilized earth wall is likely to fail under the modes of rupture, bearing failure, and toppling. The specific failure mode or combination of failure modes depends on the specific conditions and factors involved in the design, construction, and loading of the wall.