The short answer is that history.pushState (not History.pushState, which would throw an exception, the window part is optional) will never do what you suggest.
If pages are refreshing, then it is caused by other things that you are doing (for example, you might have code running that goes to a new location in the case of the address bar changing).
history.pushState({urlPath:'/page2.php'},"",'/page2.php') works exactly like it is supposed to in the latest versions of Chrome, IE and Firefox for me and my colleagues.
In fact you can put whatever you like into the function: history.pushState({}, '', 'So long and thanks for all the fish.not a real file').
If you post some more code (with special attention for code nearby the history.pushState and anywhere document.location is used), then we’ll be more than happy to help you figure out where exactly this issue is coming from.
If you post more code, I’ll update this answer (I have your question favourited) :).