I'm pretty sure that Tulyar has specified in detail on A. N. Other threat how Edinburgh's bus stops should be constructed to deal with the additional weight/power of modern buses.
Tulyar recommended setts (which is what you find in Newcastle):
http://citycyclingedinburgh.info/bbpress/topic.php?id=7282&page=4#post-79040
Other cities seem to manage to run buses without their roads crumbling to bits.
Like that London, for example.
And your own note, K, about axle loadings:
http://citycyclingedinburgh.info/bbpress/topic.php?id=7282&page=5#post-79654
It remains to be seen how Morningside Road's new surface holds up. I spoke for quite a long time with the site manager when the old surface was being removed, and he explained in great detail why it had crumbled and subsided. Something to do with the surface course and binder course being the wrong materials or not containing the correct chippings.