Integrated Qualitative and Quantitative Methodology to Assess Validity and Credibility of Models for Bridge Maintenance Management System Development

At the heart of a bridge maintenance management system (BMMS) is a set of performance prediction and maintenance decision-making models. If focused on quantitative methods alone, the ultimate validity of these models can only be established through implementation, thus delaying the applicability and acceptability of the models in practice. This is even more important for project management and infrastructure asset management domains, because the results and processes by which they are derived must be accepted by the academic and professional communities so that the new knowledge is quickly added, assimilated, and applied in daily practice. Given the poor state of physical infrastructure in many countries, the importance of improving asset management principles and practices is becoming critical. A comprehensive framework that integrates qualitative and quantitative methodologies for BMMS development is formulated, based on research and development of a BMMS model specific to Hong Kong that includes structured validation, verification, and credibility establishment. Integration of both qualitative and quantitative methods to assess validity and credibility of the models for BMMS development is expected to balance the strengths and weaknesses of each approach and lead to a more robust and reliable methodology with inbuilt credibility-building strategies. Finally, a qualitative case study of the validation methodology for the developed BMMS model shows potential sources of bias. These must be addressed in developing sound practices for applying these techniques so that research results can be more reliable and readily accepted in the field of bridge maintenance management.