In the future, Bridge Management Systems (BMS) will contain three types of BIM models for each bridge:
- An ‘as-designed’ model, produced by the design team and also containing detailed information generated by the subcontractors and suppliers. This model will contain the performance requirements and other data necessary to define the bridge’s intended function.
- An ‘as-built’ model, produced by the general contractor and reflecting the state of the bridge at the time of its completion.
- A series of ‘as-is’ models, produced by the bridge management agency through surveys of the bridge at regular time intervals.
Performance monitoring will benefit from the ability to compare the ‘as-is’ model at any time with the ‘as-designed’ and the ‘as-built’ models with automated software routines. In addition, the rate of deterioration of any aspect, such as deflections, crack propagation, corrosion or other deleterious effects will be possible given the ability to compare series of ‘as-is’ models. If the cost and effort required for acquiring the ‘as-is’ models can be reduced, they can be collected more frequently, thus enhancing the effectiveness of monitoring.
The SeeBridge project scope is focused on the compilation of the ‘as-is’ models and on reducing the cost, duration and the effort required to acquire them. The scope will include detection, identification and mapping of cracks, spalling and bleeding on the surfaces of the building components. It will exclude measurement of deflections or of drift, but the investigation of the scanning will include a set of tests to determine the accuracy that can be achieved with the various non-contact survey methods with a view to establishing the future feasibility of monitoring drift and deflection by comparing ‘as-is’ models.
In terms of the compilation of the ‘as-is’ model, the research will not assume that either the ‘as-designed’ or the ‘as-built’ BIM models are available. Given the current state of affairs, in which thousands of bridges are in service that do not have models but must be monitored nevertheless, SeeBridge scope considers the need to compile the ‘as-is’ model of a bridge based on the non-contact survey information alone.