To find suitable subject for your future research you could read review papers in the field you have mentioned. Structural Health Monitoring is one topic to take consider environmental effects on the structures using sensing technology and processing the structures response. For example you can evaluate thermal changes, climate changes and loading effects on the structures.
Here are a few topics you could explore based on your interests -
Optimizing Structural Design for Sustainability: Here you could explore how advanced computing techniques, such as artificial intelligence and genetic algorithms, can be used to optimize structural design for sustainability. You could investigate ways to reduce material usage and energy consumption while maintaining structural integrity.
Smart Structures for Resilient Infrastructure: Here you could research the integration of smart sensors and computing technology into civil infrastructure to enhance resilience. You could develop methods for real-time monitoring and response to environmental stresses, such as earthquakes, floods, and climate change.
Life-Cycle Assessment of Green Building Materials: Here you could utilize environmental science and computing tools to perform life-cycle assessments of green building materials. You could evaluate the environmental impact of materials from production to disposal and identify sustainable alternatives for construction.
Structural Health Monitoring Using Big Data Analytics: Here you could investigate the use of big data analytics to monitor the health and performance of civil structures. You could develop algorithms for early detection of structural issues and predictive maintenance, minimizing risks and repair costs.
Climate-Adaptive Structural Design: Here you could combine climate modeling and structural engineering to design infrastructure that can adapt to changing climate conditions. You could research how computational simulations can inform the design of resilient structures that withstand extreme weather events.