Kajima Corporation was founded in 1840 and is one of Japan’s leading super general contractors. It continues to build Japan’s leading high-rise buildings and infrastructure, including the country’s first high-rise building, which was considered to be impossible due to the country’s frequent earthquakes. It is expanding its business to over 20 regions.
Kajima Corporation (Kajima) was founded in 1840, and is one of the five companies in Japan known as the “super general contractors.” The company is deeply involved in improving infrastructure by constructing large-scale apartments, offices, department stores, museums, factories, stadiums, schools and hospitals as well as civil engineering projects, including roads, railroads, bridges, tunnels, dams and airports.
Fumito Ohya, acting head of the structural analysis group in the analysis technology department in civil engineering, explains, “Maintenance management has become an issue in recent years with the deterioration of infrastructure, but Kajima provides the optimal renewal technologies based on lifecycle engineering for civil engineering structures.” The company is focusing not only on building new structures, but also on maintaining and repairing existing infrastructure.
The structural analysis group engages in analysis supported by finite element analysis (FEA) for special proposals that cannot be analyzed with the usual tools used by the design department. The group investigates advanced technologies that are expected to be needed in the future based on information collected from interviews with each department in the company, and is in charge of developing alternative technologies.
With the growing need for structural analysis on a larger scale, 3D is getting more popular in civil engineering. The full-fledged introduction of construction information modeling/management (CIM) to achieve efficiency and sophistication in construction production systems is an example of this trend. Increasingly, computer-aided engineering (CAE) is being used in 3D to provide more complete data.
“Analysis is one area that our company has been particularly focused on in recent years,” says Ohya. “The (Japanese) Ministry of Land, Infrastructure and Transport issued CIM guidelines, and we are required to apply 3D analysis in various situations in the field of civil engineering design.”
Kajima’s civil engineering design spans various types of construction, such as tunnels, foundation structures, ocean fronts and harbors, bridges and nuclear facilities. For example, in the case of a tunnel, the analysis results are fed back to the design team to verify if there are any structural problems or if the reinforcement arrangement is appropriate. Product lifecycle management (PLM) specialist Siemens Digital Industries Software’s Simcenter™ Femap™ software pre/postprocessor is applied to such tasks.
“The need for 2D analysis is common in civil engineering design,” says Ohya. “However, when you try to perform a detailed investigation, the scope of what can be analyzed in 2D is limited, and the need for 3D analysis will likely increase going forward. If that happens, we will need to improve the tools further to apply them. Faced with this situation, we chose the easy-to-use Simcenter Femap pre/postprocessor.”
The superior graphical user interface (GUI), which can be intuitively operated, is a major feature of Simcenter Femap. Ohya rates Simcenter Femap highly, saying, “We compared Simcenter Femap to similar tools and found it was far easier to use than the others.”
He further explains, “In Simcenter Femap, the tree display is on the left side of the screen, the models can be shown as a list, and all tasks can be managed from the UI. In addition, the group feature is also designed to be easy to use. By using the mesh types, categorization by property and classification by groups, you can efficiently model complex models.”
Ohya also praised the geometry related features. “I feel that the geometry features are easy to use. It supports the loading of various CAD files and is user-friendly. We can use Simcenter Femap to successfully load and process CAD data that other similar preprocessors could not process or use to create a mesh from.”
Ohya states using Simcenter Femap has enabled them to streamline analysis tasks, in certain instances reducing analysis tasks from 20 minutes to one second. He says it is unsurpassed when it comes to the ease of developing custom efficiency tools using the application programming interface (API), and the technical manual makes it easy to develop by explaining all aspects of the API.
“For instance, in some cases we model a structure for a tunnel, and model the area where it connects with the ground with a spring element,” says Ohya, providing an example of using the Simcenter Femap integrated API. “We use the API to streamline the modeling of that section. In the construction field, we often attach a large number of springs. We then have to adjust the rigidity of the springs according to the size of the mesh. Doing that manually can take a lot of time. However, being able to do that automatically using the API is a significant advantage.”
He explains that previously they would calculate the distributed load and use a script or other method to configure the springs. “Before it used to take about 20 minutes to perform a series of tasks, which included dummy data output, conversion script execution and data merging. With Simcenter Femap automation, we can accomplish the same tasks in less than one second.”
In addition to ground spring configuration, Ohya explains that they are also applying the API in various situations to achieve operational efficiency and reduce management time: “With Simcenter Femap, you can close the modeling work in the UI so it’s easy to manage the data or edit and modify the data at a later date. Because there is no need to partially load separately created data, the operational efficiency is remarkably improved.”
Ohya further explains they were particularly impressed by the desire of the Simcenter Femap development team to meet user needs: “Last year we participated in the Simcenter Femap user round table, and we were able to speak directly with the person in charge of development. This meeting wasn’t just about unilaterally communicating user opinions and requests; we were also able to hear specifically about how the development team is supporting Simcenter Femap and what they plan to do in the future.
“We were also very grateful that they listed the requests from each user and promised to keep us up-to-date on their progress. I am hopeful the feature I need will be implemented in the near future.
“We rely on the continuing development of Simcenter Femap. Its basic structure is robust, and we find good new capabilities in every new version. We are confident this will continue in the future.”
Ohya states that sharing information with other attendees from the same industry at the user round table was extremely meaningful, and they hope to continue to participate.
Kajima is already applying Simcenter Femap in various situations. Ohya says, “I think Siemens is always working toward removing the barriers between modeling and analysis, and we look forward to that continuing. For example, I think it would be great if analysis became more common and could be achieved with a couple of operations, such as creating a template from the operation history or creating a mesh from a CAD model. We are looking forward to future advances in Simcenter Femap.”