Hrb

(c) The wedge subject to a normal end load — Figure 8.40(a)

From a combination of these cases any inclination of the load can easily be handled.

(d) Uniformly distributed normal load on part of the surface - Fig. 8.41

The result for orr obtained in eqn. (8.124) can be used to examine the case of a uniformly distributed normal load q per unit length over part of a surface-say 9 — f. It is required to find the values of the normal and shear stresses (cr^, oyy, zxv) at the point A situated as indicated in Fig. 8.41. In this case the load is divided into a series of discrete lengths <5x over which the load is 8P, that is SP = qSx. To make use of eqn. (8.124) we must transform this into polars (r, 9). That is dx = rd9/cos9. Thus, dP = q ■ rd9/cos9 (8.128)

q/unit length /

qMWWHt

Fig. 8.41. A distributed force on a semi-infinite plate.

nr n

The total stress values at the point A due to all the discrete loads over 9\ to 02 can then be written,

0 0

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