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Long-span suspension bridges require accumulated design and construction technologies owing to challenging environmental conditions and complex engineering practices. Building information modeling (BIM) is a technique used to federate essential data on engineering knowledge regarding cable-supported bridges. In this study, a BIM-based master digital model that uses a data-driven design for multiple purposes is proposed. Information requirements and common data environments are defined considering international BIM standards. A digital inventory for a suspension bridge is created using individual algorithm-based models, and an alignment-based algorithm is used to systematize them and generate the entire bridge system. After assembling the geometrical model, metadata and various BIM applications are linked to create the federated master model, from which the mechanical model is derived for further stages. During the construction stage, the advantage of this digital model lies in its capability to perform efficient revisions and updates with respect to varying situations during the erection process. Stability analyses of the bridge system can be performed continuously at each erection step while considering the geometric control simulation. Furthermore, finite element analysis models for any individual structural member can be extracted from the master digital model, which is aimed at estimating the actual behavior of bridge members. In addition, a pilot master digital model was generated and applied to an existing suspension bridge; this model exhibited significant potential in terms of bridge data generation and manipulation.
Cable-supported bridges, whose service life can exceed 100 years, represent the most significant investments in national transport networks. During its service life, there is a big challenge for bridge engineers in terms of maintaining the suspended structures in a safe condition; otherwise, it can cause many serious problems. For example, an unexpected disaster of bridge collapses leading to the lack of transport links can result in significant social problems, as suggested by the recent collapse of the Morandi bridge [1]. Moreover, the main cables in a suspended system are assessed based on the tension force they experience and their safety factors; however, a visual inspection is recommended only after a period of 30 years [2]. Recently, a methodology for evaluating the remaining service life of bridge cables was introduced [3]. New approaches for knowledge sharing necessitate learning from similar cases and avoiding such accidents. This varied knowledge, ranging from the first phase of bridge construction to the next 100 years, can then be utilized. The limitation of existing information storage and collection systems, which are operated by a few experts, is apparent.
It can be considerably difficult for engineers to determine appropriate structural systems where the following aspects are balanced: optimization of weight and cost, guaranteeing aerodynamic aspects during construction and service periods, and feasibility of construction [4]. Among the various types of bridges built worldwide, suspension bridges are considered superior in terms of aesthetics. Following the concept of a long-span bridge, the main advantage of suspension bridges is their ability to bridge considerably long spans, such as over deep water bodies where it is not possible, or significantly expensive, to build foundations for piers supporting the shorter spans of other types of bridges. However, the long spans of these bridges result in problems primarily associated with the construction process, aerodynamic stability, and the impact of self-weight on the static load of the bridge [4, 5, 6]. When engineers create an effective design that counters these problems, the potential of the design is abundant. However, in the absence of such an effective design, a significant risk of collapse exists, which must be considered.
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The conducted comprehensive review and critical analysis of a total of 198 publications in terms of building information modeling for transportation infrastructure have presented the state of the art of BIM implementation in this field, including the overview of the BIM domains, BIM applications, data schemas, and BIM uses [7]. It shows that there was an improvement in BIM research and application development for transportation infrastructure in general, especially for highways and bridges. It also highlights the current status of research, the usage of emerging technologies, and significant research gaps that still need to be addressed. On the other hand, it summarizes the constraints and challenges facing the transportation industry, highlighted the significant need for interoperability and existing interoperability initiatives, and presented recommendations to support future research. Recently, bridge information modeling (BrIM) was proposed for the innovation of bridge construction processes from planning to operation. Bridge information modeling (BrIM) using open parametric objects was introduced in detail by the FHWA (Federal Highway Administration, which is sponsored by the U.S. Department of Transportation) [8]. They opened the data schema, named OpenBrIM Platform, which focuses on transforming bridge practice from paper delivery to digital delivery, developing digital BrIM standards, providing interoperability between many platforms and life-cycle stages, and maintaining software neutrality. Based on that open XML data, the user can freely adapt and develop their own BrIM model for a certain purpose, such as a bridge monitoring system [9].
The 3D geometrical models for existing bridge structures can be created in various ways depending on the capability and resource of the originator. The geometric representation comprising each structural member can be referred to as the IFC Bridge model, which aims to flexibly link geometric representations with semantic objects [10]. IFC schema can be learned and developed for the bridge information system by appropriate compiling IFC Bridge and IFC Infrastructure extensions [10]. On the other hand, recently the author of this paper and his research team have widely introduced the digital information models using the BIM technique for various types of bridges, such as cable-stayed bridge [11, 12] and prestressed concrete bridge [13, 14, 15]. The alignment-based object-oriented design philosophy appears to be essential for the creation of a bridge information model. By applying a set of parameter definitions and appropriate algorithms, the entire bridge model can be realized without any discontinuity. The parametric design concept enables designers to alter any input factors of the model in order to match the target requirements. Moreover, during its lifecycle, the digital bridge model significantly helps engineers in managing the flow of information for multiple purposes. The interoperability of the design platform allows collaborative work among various stakeholders and stages of the project.
Cable modeling for suspension bridges is a major challenge for engineers. There is no unique undeformed configuration for cable structures in the stress-free state; this is because any applied tension generates lateral stiffness in the cable. Therefore, only the deformed shape of a cable structure under dead loads, which is predetermined at the design stage, is similar to the framed structures. The undeformed configuration of a frame structure is predetermined during the design process based on functional specifications and the experience of engineers. Basic analysis tools that are based on predefined undeformed configurations can be easily used to measure the displacement field under dead loads because framed structures possess an initial rigidity that is independent of the applied load. However, a specific undeformed configuration for the equilibrium state of a cable structure under a dead load has not been reported thus far. This is because the lateral rigidity of a cable, caused by the applied tension, can be considered as a distinctive mechanical property for general cable structures. Owing to its self-weight, a cable is loaded even without any externally applied loads; hence, sufficient tension should be applied to the wire to counter the self-weight in order to target the desired configuration [16, 17, 18]. The concept of an elastic catenary cable element has been widely introduced for the main cables of suspension bridges [19].
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Owing to the existence of an extensive range of variables, including construction methods, temporary supports, and alteration loads, geometric control for suspension bridges is always a difficult task. Moreover, for the main cable, geometrically nonlinear effects and multiple tension loads should be considered. During the construction stage of a suspension bridge, the cable profile continually changes according to the load, leading to a change in the specific geometrical configuration of other
Owing to the existence of an extensive range of variables, including construction methods, temporary supports, and alteration loads, geometric control for suspension bridges is always a difficult task. Moreover, for the main cable, geometrically nonlinear effects and multiple tension loads should be considered. During the construction stage of a suspension bridge, the cable profile continually changes according to the load, leading to a change in the specific geometrical configuration of other
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