The transmission of ground movement to structures

The nature and extent of ground movements resulting from the extraction of coal can be predicted with a fair degree of accuracy as a result of extensive research carried out in the past. There is, however, little quantitative information about the effect of such movements on structures. This information is necessary for the protection of existing structures from damage due to mining operations and for the design of new structures for erection in mining areas. The work described here was carried out to study the factors governing the transmission of ground movement to structures, and the damage arising from the transmitted movement. Section 1 is concerned with theoretical aspects of the transmission of ground movement to structures. The effects of vertical and horizontal movements are considered separately. In each case an expression is derived for the critical length of structure at which damage will occur. Tests on existing structures which were subject to mining subsidence are described in Sections 2 to 4. The development and application of suitable techniques for the measurement of horizontal and vertical movements of ground and structures, and for the measurement of wall tilt, are described. Damage which occurred to the structures is listed and is related where possible to measured ground movements. Section 5 describes tests which were carried out with sand models to study movements in a cohesionless mass subject to horizontal extension