Environmental Engineering Reference
In-Depth Information
10
Ground Subsidence, Collapse, and Heave
10.1
Introduction
10.1.1
General
Origins
The hazardous vertical ground movements of subsidence, collapse, and heave, for the
most part, are the results of human activities that change an environmental condition.
Natural occurrences, such as earthquakes and tectonic movements, also affect the surface
from time to time.
Significance
Subsidence, collapse, and heave are less disastrous than either slope failures or earth-
quakes in terms of lives lost, but the total property damage that results each year proba-
bly exceeds that of the other hazards. A positive prediction of their occurrence is usually
very difficult, and uncertainties always exist, although the conditions favorable to their
development are readily recognizable.
10.1.2
The Hazards
A summary of hazardous vertical ground movements, their causes, and important effects
is given in
Table 10.1.
10.1.3
Scope and Objectives
Scope
Ground movements considered in this chapter are caused by some internal change within
the subsurface such as the extraction of fluids or solids, solution of rock or a cementing
agent in soils, erosion, or physicochemical changes. Movements brought about by the
application of surface loads from construction activity (i.e., ground settlements resulting
from embankments, buildings, etc.) will not be considered here.
Objectives
The objectives are to provide the basis for recognizing the potential for surface move-
ments, and for preventing or controlling the effects.
