Sliding force

For example, consider the crack tip as it intersects a fiber (Fig. 16). The local stresses at the tip can cause fiber-matrix debonding. The crack tip continues to open causing the interfacial debonded region to extend. The fiber continues to interact with the matrix through a frictional sliding force even after the initial bond fails. The distance over which the force acts is the debonded length times the difference in strain between the fiber and the matrix. 

In order to estimate the extent of decrease in the particle velocity due to the pipe curvature, it is assumed that the drag force is negligible in comparison with the sliding force of the particle on the bend surface. With this consideration, Eq. (11.51) is reduced to... 

The coefficient of friction n is defined as the force fF required to initiate and maintain sliding divided by the load "W applied perpendicular to the surface l = fF/W. The coefficient of friction is found to be independent of the area of contact over a wide range of loads that cause plastic deformation. The reason for this is that both force and load are proportional to the same area of interface contact. For plastic deformation, we have already shown that W = Ap, where p is the average pressure over the contacts and A is the area of contact. At the contacts, chemical bonds are made that must be sheared or broken as one solid surface slides over the other. If the shear strength 5 is constant, the force S required to shear these contacts equals the area of contact times the shear strength (S = /4s). If materials of comparable hardness are brought into contact, the sliding force is equal to the shear force and proportional to the area of contact. Therefore we can write /A = (F/ W = s/p this observation that the frictional force is independent of contact area is known as Amontons law. 

Putting Equation (10) into Equation (6), the anti-slide force can be got which induced by difference of shear force under the slope s incline face. can be written as Equation (11). 

R and R2 added together are resultant anti-slide force induced by difference of shear force, the stability factor K of improved SBM can be calculated finally if the resultant anti-slide force be added into traditional SBM s anti-slide force. 

V.35. The horizontal force on the plane of the base is R. As the packaging is effectively fully chocked by bolting, the sliding forces to be withstood by the bolts on adjacent sides are Ma and May, respectively. For the bolts to be designed to resist R, they must be of the shear bolt type. 

LIU Yuan. Study on apparent sliding force for slope sliding—an example from the lianziya dangerous rockmass[J], Journal of Engineering Geology, 1999. 7(3) 272-278. 

However, for mechanical reasons, it is desirable to preoxidize zirconium. Properly oxidized zirconium has a much improved performance against sliding forces, although it can be damaged by striking action. Oxidized zirconium pump shafts are an example of a common application. Bolts and nuts are often oxidized for the purpose of preventing galling. 

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