When it comes to Manufacturing 4.0, the automotive and mechanical engineering industries are frequently referred to for orientation. In these sectors, everything is stored in digital models as well and the interaction between digital drawing and designing (CAD) and digital manufacturing works perfectly. The presence of human workers in factory halls is becoming an increasingly rare occurrence. Robots are moving swiftly and with pinpoint accuracy through digitally connected bays. Plus, the material that’s picked from high-bay warehouse racks by self-driving forklift trucks autonomously moves on self-driving pallets, guided by induction loops – at the right time to exactly the right place. Welcome to Factory 4.0. And what about construction sites? Digital transformation is forging ahead here as well. While GPS-controlled surveying instruments and autonomous construction machines have long been part of site equipment, Building Information Modeling (BIM) is a term that’s now becoming increasingly important.

The BIM planning method

So, what exactly is BIM? Building Information Modeling is no special software but describes the perfect interaction between a variety of software solutions and database systems. Just like every technical construction crew uses specialty tools, the software applications for planning, procurement, construction and utilization processes vary. BIM is like a digital machine that sorts and connects these processes. One of the key prerequisites for this is the availability of all data according to the IFC (Industry Foundation Classes) standard.

Building Information Modeling is still in its early development stages, but already improves adherence to project deadlines and budgets. The reason is that BIM – marking a major evolutionary milestone in this context compared to CAD – provides digital renderings of three-dimensional rooms, but also calculates time and cost parameters as a fourth and fifth dimension. Unsurprisingly, BIM is now a mandatory element of public tendering procedures in many countries.

Digitalization is bringing a new building culture. For the architect, it is a paradigm shift

Matthias Kohler,
Professor of Architecture and Digital Fabrication ETH Zürich

Evolutions are planned to elevate BIM to a level of creating a dedicated, connected virtual world: a digital twin of the entire construction project. Provided that the plan pans out, this new construction world will also incorporate the Internet of Things (IoT) and cyber-physical systems including machine control, sensors and real-time monitoring.

In spite of all the digitization and connectivity it features, BIM cannot and should not replace personal dialog and the shared understanding of a standardized organizational structure and workflow. The hardware and software as well as the databases here merely supply the requisite infrastructure and provide all the parties involved in a construction project with direct access to the relevant information at any planning stage. Plumbers and tilers are able to match their data and also share them with painters and electricians as needed. And if a crane for installing an elevator fails, all the technical crews affected by the equipment downtime will receive an alert in real time. Ideally, a plan B that minimizes the loss will be sent along with the alert.

From planning to teardown

BIM supports the entire lifecycle of a building or facility, from initial planning to construction and use to potential dismantling including environmentally compliant disposal. The latter aspect can be taken into account as early as in the planning stage and therefore closes the loop.

In the construction stage, the machines involved can be controlled using so-called BIM2Field applications. This is an increasingly important factor, because – just like factories – construction sites are using more and more advanced technologies. Even at this juncture, self-driving machines exist that distribute materials at the site just in time. Drones assist with surveying work and inspections. The successor of the bricklaying robot Hadrian X is said to be able to join 1,000 bricks together per hour instead of the previous 200. Plus, a huge 3D printer produced the first three-story 12.5 by 17.5 by 7.5-meter (41 by 57 by 25-foot) residential building on-site in Germany this fall – at a breathtaking speed of processing 10 metric tons (11 short tons) of a special cement per hour.

At the end of October 2020, construction equipment manufacturer Hilti unveiled its semi-automated mobile construction robot for overhead drilling jobs. The so-called Jaibot is able to independently and accurately position itself in interior spaces, drill holes and subsequently mark them for the various construction crews. The autonomous system is easy to use without expert knowledge. Hilti has no doubts that digitally planned construction projects and their implementation using BIM-capable robotic solutions promise to deliver a significant productivity gain. In addition, robotic solutions can mitigate the shortage of skilled labor.

Bearings for buildings

© Schaeffler

For 75 years, engineers in the construction industry around the world have been relying on Schaeffler’s plain bearings and consulting expertise. Hydraulic motion control cylinders for construction machines, grinding rollers in cement mills, continuous casting lines in steelworks, articulated pendulum joints for optimal steerability in roller-compactors, train doors and bogies, escalators and luggage belts at airports: all of them require plain bearings.

In buildings, plain bearings are used at particularly critical interfaces like in the glass roof of Berlin’s Central Train Station. The roof structure covers approximately 300 meters of railroad platform. Countless spherical plain bearings and bolt systems from Schaeffler are installed in the trussed frames, providing the necessary length compensation in the steel structure when external influences, particularly wind, act on it.

The weight of the roof structure at London’s Wembley Stadium rests on just two bearings from Schaeffler. Each of them supports a weight of 7,500 metric tons (8,270 short tons) and has been designed for a service life of 100 years.

Perfect planning, saving resources

The digital twin can supply not only the control data for such high-tech machines. Even traditional construction machines like excavators, dozers and road pavers have long begun to feature 3D machine control units that are fed with digital BIM and terrain models. Entire civil engineering models are shown to the machine operator on a display and facilitate faster and more precise work.

Look before you build

The digital twin offers another major advantage even before the first sod is turned: Thanks to VR headsets, clients can take a virtual walk through their projects to get a highly realistic impression of the planned outcome. As a result, the client’s wish can be compared with reality while the project is still in the planning stage, which practically precludes the risk of costly corrections after construction has begun. Even if the client should subsequently desire modifications, BIM will concurrently inform all the technical crews involved and warn them of potential issues that may be caused by the change in plans. In addition, material orders can automatically be adjusted and documented down to the smallest washer.

But BIM-optimized logistic processes not only cut construction costs and time. They also help reduce the consumption of so-called embodied energy, in other words, the energy required for production, storage, shipping, processing and disposal of construction materials.

The subsequent operation of the facility as a whole is significantly simplified and incurs less costs due to digitally connected planning as well. Experts refer to this as BIM2FM, with FM standing for Facility Management. In this context, it’s important to know that the lion’s share of a facility’s total costs is not incurred during the planning and construction stage, but that the greatest savings potential exists in the utilization stage. That’s why, as early as in the planning phase, all parameters such as insulation performance, heating output and ventilation data as well as the subsequent room temperature and energy costs at varying times of the day and during different seasons are calculated in advance. As a result, the digital BIM facility model becomes a ­real-time based control, monitoring and measuring center that technically and economically optimizes a building’s entire lifecycle. Here’s a case in point in this context: even before construction starts, architects can rotate and move the digital twin around the site, and simulate various locations in fast-forward mode across the four seasons in order to identify the building’s energetically optimal orientation and design, among other criteria.

Sorting the data maze

To prevent users from getting lost in the data spaces of a BIM model with many terabytes, the total information and complex pictures are split into layers in which the relevant data for the respective construction teams are stored. Structural engineers, for example, are only interested in data pertaining to the building’s design and structure, while façade planners will only be dealing with its exterior shell. Every planned, used or potentially used component is stored in a BIM-compatible database. In addition to the classic dimensions, facts about materials such as their thermal conductivity and flammability are important. Even the source from which a material was purchased can be identified at a later point in time by just clicking the relevant detail. The gaps and relations between adjacent components are captured as well.

Much of the BIM potential described here is still a vision. But when Henry Ford introduced the moving assembly line, he was a visionary, too. Nobody was ready to believe that it was possible to break down the production of complex goods or products into individual, monotonous steps. And that was just the beginning of progressive industrialization and automation. Aldous Huxley’s novel “Brave New World” begins with an epigraph in French that might be translated into English as “Utopias appear much more attainable than formerly was believed.” The construction industry has been following this proposition more than ever before. The BIM digital planning method and innovative production technologies create all-new opportunities for design that can also be achieved faster and at lower costs. Perhaps living in style and in complex architecture will soon become affordable for everyone. This would be true progress. The odds are in its favor. Welcome to the new building world.