I develop a framework for C&D waste management that shows the best sustainable strategy throughout the project, from pre-construction to demolition. Now I need your advice for validation of the framework. is there any idea about it?
Use case studies, perhaps you may focus on each lifecycle stage. You can also use focus group interviews such that a 'college of experts' will advice you on the strength of the tool you have developed
The next step is to pilot it on a variety of case studies, monitor the outcomes and modify your framework accordingly (if you have not already done so). As well as the "college of experts" other responders refer to, you can also publish in a reputable peer reviewed journal. That will provide extra feedback.