Abstract
Concrete is widely used in infrastructure.Due to its characteristics and environmental impact,concrete structures generally have durability problems[1].Maintenance management,therefore,must be carried out during the service period of concrete structures.Factors causing the durability problem of concrete structures include carbonation,rebar corrosion,freezing and thawing,alkali silica reaction,chemical erosion,and so on.By analyzing the mechanism and process involved in the durability problem caused by those factors,a maintenance manager can evaluate the deterioration degree,and finally makes decisions on a method of intervention according to the evaluation results.
However,conducting the durability analysis usually involves professional knowledge which is mastered by experts,and a maintenance manager is usually unable to do the analysis alone.The maintenance manager needs to consult experts to get analysis results.The knowledge gap between experts and managers makes knowledge utilization inefficient and leads to inefficiency in management.Moreover,durability needs to be analyzed multiple times throughout the maintenance management process of structures.After using knowledge to build a durability analysis model,it is very ef ficient to preserve and apply it to a similar durability problem in the future.Therefore,this paper attempts to explore a method to break down knowledge barriers for durability analysis.
Knowledge management[2]is proposed to promote knowledge sharing between experts and non-experts such as managers in terms of framework and process.Knowledge management is mainly composed of the following two steps:knowledge creating and knowledge sharing as shown in Figure 1.
Figure 1 Workflow of the knowledge management
Knowledge is a familiarity,awareness,or understanding of someone or something,which is acquired through experience or education by perceiving,discovering,or learning.Knowledge exists invisibly in the brains of experts in the initial state[3].In the knowledge creating(which also means the externalization of knowledge),an expert as a knowledge provider should retrieve the corresponding knowledge of durability analysis to build an analytical model and then apply it to a durability problem to be solved with visual tools.Advances in computer software,such as a finite element software and a discrete element software,have made it possible to decode expert's knowledge into a complete visual form such as a simulation model from ideas.
In the information sharing,due to the dif ferent needs and purposes of the participants,the levels of knowledge requirements are varied.The knowledge providers focus on the knowledge itself to conceive a model to simulate the reality as completely as possible,so they have high level of knowledge requirements.Since the knowledge receivers(usually as managers without professional knowledge reserve)are mainly engaged in engineering practice,focusing on the application of knowledge.They only need to carry out the durability analysis through a simulation model with simple operation,so they have low level of knowledge requirements.To eliminate the confusion caused by dif ferent levels of knowledge requirements in the process of knowledge sharing,the providers need to simplify a knowledge model and customize a user interface to meet the level of knowledge requirements of receivers.Open parameter models would be adopted to realize the simplification of the simulation model by experts,in which various theories applied in the analysis are hidden,while the parameters and oneclick calculations are operational.In addition,the results of analysis in open parameter models should be visible.Knowledge receivers can access the knowledge from the user interface and reuse the knowledge through the open parameter models.
The transmission of knowledge requires a carrier that exists in a visual form.A platform which can store and display the knowledge in the form of simulation model is used as a carrier to share the knowledge.Both people of knowledge provider and knowledge receiver can access the knowledge from the platform.The platform is a BIM-based integrated information platform[4],which ensures visualization and persistence in information storage.BIM is designed as a visual tool for management of structures with 3D models,and BIM software can be customized with new features via API(application programming interface)(Figure 2).Cloud technology[5]used for communication via the internet on this platform ensures that managers can access and process information of various forms anytime and can easily share information with others.
Figure 2 Im plementation of BIM-based integrated information platform
A case study on the durability analysis of chloride ion penetration into concrete tunnel was carried out to demonstrate the implementation process of the proposed approach.An open parameter model was created to simplify the simulation model.Then an information platform was established in BIM software,and eventually the open parameter model was successfully stored and displayed on the information platform.The results showed that knowledge management can be applied to durability analysis with the use of information tools.
The method presented in this paper gives useful instruction in the knowledge sharing between experts and managers breaking the knowledge sharing barriers in knowledge contents and knowledge carrier forms.By using necessary knowledge,a manager can make durability analysis alone to make timely decisions with the analysis results,ultimately improving the efficiency of maintenance management.