Construction

POSCO delivers not only the high quality, high strength steel used in skyscrapers but also a
wide range of solutions for optimal construction including welding, design and performance testing, writing a new chapter for the erection of high rise buildings.

For the construction industry, POSCO is a dependable supplier of structural steel and highly functional finishing materials featuring diverse designs and good performance. Our products for civil engineering are extensively used for large scale suspension bridges and girder bridges.

Interior and Exterior

It is the major finishing material determining the interior and exterior of a building by using steel with various patterns and colors, and the panel that provides a safe and sound environment through insulation and fire resistance securement. This steel features a lower vulnerability to rust under the atmospheric influence and a good resistance to corrosion. The internal and external steels are less rusty and corrosion resistant in the atmosphere than the general steels, and weather resistance steels, PosMAC or stainless steels are applied.

Related Products
Weather Resistance Steel(HR) Weather Resistance Steel(Steel Plate) GI/GI(H) PosMAC Pos Treatment Steel Austenitic Series(300 Series) Ferritic Series(400 Series)

Construction Application Technology

[INNOVILT LAB] #3 Say Goodbye to Heavy Scaffolding, Meet Hybrid Jack Support
Meet INNOVILT LAB, the place where the best INNOVILT products are created. It is a kind of a base camp where POSCO is undertaking R&D for the next generation INNOVILT products.The INNOVILT product to be introduced today is “UL700 Steel-Aluminum Hybrid Jack Support”. POSCO Newsroom presents to you the story of a POSCO researcher who developed the product together with POSCO’s client, Daehan Scaffolding.

l Temporary Materials? Safety Materials!

I am Tae-Hyu Ha, a senior researcher at POSCO Steel Structure Research Group. I am working on developing construction materials using POSCO steel, and today I am going to tell you the development story of “temporary materials“.Let’s picture the construction of a building. Laying down the base work, building a framework, installing floors and ceilings, applying interior and exterior materials, and decorating the interior — these might probably be the construction processes that come to mind. However, there is one crucial process missing here. It is none other than “temporary work”.Temporary work is the phase where temporary and basic structures necessary for construction are installed. It includes bringing in electricity for the construction tools, installing water facilities for drinking and sanitizing, and establishing safety facilities to prevent accidents. And “temporary materials” are essential in this temporary work. Temporary materials include walk plates and passages installed to enable work at high areas, supports that temporarily hold the building framework, and a double-deck that allows vehicles and pedestrians to walk above the construction section. Put differently, proceeding with construction is impossible without temporary materials.Temporary materials are especially important in that they directly affect the quality of construction and the safety of workers on site. However, in most cases, they aren’t paid much attention because they are demolished once the construction is complete. Since temporary materials are perceived to be materials that are used for a short time anyway, many try to shorten the construction period by setting them up quickly and reduce costs by utilizing cheap materials imported from overseas.▲ High-strength system scaffolding installed on sitesIn this situation, POSCO set to pioneer the temporary material market using premium steel materials with its clients from 2009 as a measure to secure the safety of construction sites. The goal was to bring about a change in perception that temporary materials are not just temporary but are safety-related materials that are directly connected to the safety of workers. As a result, POSCO developed the premium steel tube “UL700 (Ultra Light 700)” for “scaffolding”. POSCO’s high-strength steel PosH690 was applied as the material for UL700.What is scaffolding? Well, when passing a remodeling site or a construction site, you might have seen a structure where narrow steel pipes are woven together vertically and horizontally as if they were wrapping the building. This is called scaffolding, and it is a kind of a walk plate that enables workers to safely climb up and down in the construction of high-rise buildings. Scaffolding made with UL700 adopts POSCO premium steel and has a tensile strength of 700 MPa, replacing conventional scaffolding that mainly uses general steel pipe of 400 MPa tensile strength.In the beginning, expanding high-strength premium products in the price-oriented steel pipe market was not easy. However, after receiving positive feedback from construction sites and being recognized for its economic feasibility and safety, demands for the products began to expand gradually.

l Making the Temporary Column “Jack Support” as Premium

As recognition for UL700 with its safety and high strength performance grew, product inquiries rushed in not only about scaffolding but about various other temporary materials. Then one day in February 2016, Min-Young Jeong, CEO of Daehan Scaffolding, visited the POSCO R&D Center in Songdo and shared his story with us.“We are a company that manufactures and supplies a product called Jack Support. Jack Support is used to distribute the load of the upper part of a building. When concrete is poured on the floor, its strength increases as the concrete hardens, but it usually takes more than a week for the concrete strength to become sufficient. So, to proceed with construction on the upper floor, temporary support must be installed under the floor plate while the concrete is hardening and the temporary support used here is Jack Support.”▲ Jack Support applied on construction sitesHe went on, “However, we have a problem. For places with high ceilings, such as the lobby and public space on the first floor, a Jack Support of at least 5m is required, but the problem is that as the product length increases, the weight increases as well. Manufacturing and supplying aren’t a problem but installing a product weighing over 100kg is a definite issue. Imagine that workers have to lift, move, and install a material that weighs over 100kg. So, that’s why we need to develop a Jack Support that is light yet long enough. I heard that there is a steel pipe for scaffolding called UL700, and I wondered what if we apply such high-strength steel to Jack Support as well.”Jeong’s suggestion was plausible, but I was not too sure. I could not help but think, “Oh, length issues. Again”. It was because I knew from my experience that when high-strength steel is applied to a long material, the performance does not come out properly due to “buckling”. Buckling is a phenomenon where a material, which has a long length compared to its cross-section, suddenly bends when the load is applied above the limit it can hold up. In the case of short types, high-strength steel can withstand much heavier loads without bending, but with the length increasing, even high-strength steel bends under similar loads as ordinary steels due to this buckling effect.I said, “CEO Jeong, Since buckling occurs in long materials, it is highly likely that the results might be indifferent even in the case of high-strength steel. So, let’s design products by length using high-strength steel first, and then conduct performance tests with the prototypes. Detailed directions can be discussed later.”First, as CEO Jeong suggested, I set on designing a standard-type Jack Support (with a height of 3 to 4m) and a high ceiling-type Jack Support (6 to 10m). The idea was to make four prototypes, two for each type — one with normal steel SS40 and the other with high-strength steel PosH690 — and check the maximum load each product can support. The design details were sent to Daehan Scaffolding and they were produced accordingly. Two months later, we met again at the Songdo R&D Center to evaluate the performance. After inspecting the completed prototype, we carefully started the testing. The results turned out as expected. The standard-type Jack Support adopting high-strength steel exhibited similar performance to conventional products while reducing the overall weight. However, in the case of the high ceiling-type Jack Support, both the high-strength prototype and the normal prototype didn’t meet the required performance, which is a maximum load of 30 tons.Things didn’t work out as CEO Jeong had expected, and it was a little disappointing for us as well. We couldn’t attain the desired results, but we couldn’t stop there. We carefully made a new proposal.“Developing a high ceiling-type Jack Support is difficult right now. How about applying high-strength steel to the standard-type Jack Support instead? As you could see in the testing, if high-strength steel is applied on the standard-type Jack Support, the product weight can be drastically reduced. It could enhance the price competitiveness of the product as well.” CEO Jeong considered our offer for a while and replied, “The product is widely applied, and the market is much larger, so it would be worth a shot. Let’s do it!” After that, we set on several detailed design and performance tests, and we finally launched a high-strength Jack Support with a maximum length of 3.8m.It wasn’t a product of the initial plan, but the response from the market was hot! The secret was its lightweight, which is about half the weight of conventional products. It was an opportunity to capture the need for lightweight Jack Supports in the market. In construction sites, time and labor force are important, so the demand for high-strength lightweight products gradually increased, and the client company producing and supplying these products became busier than ever.

l Steel & Aluminum Together! The Advent of a Hybrid Jack Support

In November 2018, almost three years later, Daehan Scaffolding CEO Min-Young Jeong contacted us for another visit to the research center. Since the commercialization of the high-strength Jack Support, we hadn’t received any direct communication, so CEO Jeong’s contact was quite a surprise. Was there any problem? The story of CEO Jeong was as follows.“Currently, our product is the lightest among domestic steel Jack Support products. The market has also expanded. But recently, more and more companies are making Jack Supports with aluminum. Aluminum is supposed to be expensive, but the price of these products aren’t very different from our products as well. So, I would like to take a chance to upgrade our products once again.”There were two things that Daehan Scaffolding desired. The first was expanding the maximum length of use from 3.8m to 5m. CEO Jeong explained that the length of the product had to be increased than the present to respond to various demands on the field. The second was extending the range of length adjustment. The adjustment range of current products is only 30cm, and so to meet the length requirements of each construction site, the products have to be manufactured accordingly, resulting in over 10 different types of products, which is too many. CEO Jeong wanted to extend the adjustment range to 70cm with a single product that could be applied to more sites.Listening to him, I realized that it was similar to what we had worked on three years ago. As I was going to say, “Let’s try a new method since it’s difficult to do that with high-strength steel.” CEO Jeong proposed an idea, “We designed a product where the length can be adjusted by inserting an aluminum inner tube into a UL700 steel pipe.”Combining aluminum and steel? At first, it sounded like a non-realistic plan. I thought, ‘This product can be made with steel alone. Why should we apply aluminum here?’ But my thoughts soon changed as I saw the prototype sample. Since the aluminum inner tube allows precise machinability, it became easy to secure the straightness of the product, and the strength of the product was also steady thanks to the application of high-strength steel. Making the outer tube, which must withstand the load, with high-strength steel, while making the inner tube for length adjustment with aluminum to reduce the overall weight — it seemed like a workable idea.We decided to come up with an optimal design based on the client’s prototype. First, we worked on finding the coefficient for the complex aluminum section design. Next, we calculated the buckling load of the steel pipe by length and improved the thickness of the steel pipe and the shape of the aluminum section accordingly.Four types of test specimens were produced by different lengths, and load testing was conducted for each. The commercial product lineup was also complete taking into account the test results and the most required height at construction sites. Considering the buckling strength and field workability of the inner tube, the length of the aluminum inner tube was set to 1m, and it was produced in four different sizes. After a year of research and testing, we finally launched a high-strength hybrid Jack Support with aluminum inner tube in July 2019. It was such an achievement in 4 years since the first meeting with Daehan Scaffolding in 2016.

l Safety for Workers, Economics for Contractors

The collaboration of steel and aluminum — the two different competing materials — was embodied into this Hybrid Jack Support. And within a year of its introduction to the market, it has been applied to more than 30 apartment construction sites of leading domestic construction companies, such as Hyundai E&C, Daewoo E&C, and POSCO E&C.▲ The UL700-Al Hybrid Jack Support applied on siteCEO Jeong said, “The product is really good because it’s light — this is what I hear a lot when supplying the products.” We started with the application of high-strength steel to temporary construction materials, which led to the development of ultra-lightweight, high-strength Jack Supports, and, finally, here we were with Hybrid Jack Supports.Compared to the conventional 5-inch product, the Hybrid Jack Support has the same strength but is 50% lighter. It also weighs about 80% of an aluminum product. Since UL700 is high strength steel, it is possible to reduce the outer cross-sectional area to one-third of that of aluminum, which results in remarkable weight reduction. Supposing that the conventional Jack Support is 60kg, an aluminum product is 35kg and the Hybrid product is merely 29kg. Other than the fact that it can be handled more safely by the workers, what meanings do this ‘lightweight’ feature have on sites?The most crucial fact is that it can be installed quickly due to its weight reduction. 29kg is a weight that a single worker can easily handle. Also, unlike conventional products, the length can be adjusted up to 70cm without bolts, so it allows quick and convenient work.See how a worker installs a Hybrid Jack Support on site in just 35 seconds!<span data-mce-type="bookmark" style="display: inline-block; width: 0px; overflow: hidden; line-height: 0;" class="mce_SELRES_start"></span><span data-mce-type="bookmark" style="display: inline-block; width: 0px; overflow: hidden; line-height: 0;" class="mce_SELRES_start"><span data-mce-type="bookmark" style="display: inline-block; width: 0px; overflow: hidden; line-height: 0;" mce_selres_start="">?</span></span>The simple and quick installation enables a reduction in labor costs and shortens the construction period. In fact, there was a case where labor costs were reduced by more than 30% as the time required to install and disassemble products was shortened. Also, since a more number of products can be loaded on the trucks to carry them, transportation costs are reduced by about 30%.However, there may be doubts like, “Wouldn’t there be a problem with durability if it becomes so light?” There might be concerns about the inner tube made of aluminum being damaged on sites. But the product we aimed to manufacture was a ‘light yet strong temporary material’ — not just a light one. Unlike conventional products, the Hybrid Jack Support is designed to be separated by parts, so there is less risk of damage, and even if it is damaged, the damaged part can easily be replaced, so the maintenance cost is also low. The exterior of the Hybrid Jack Support is made of POSCO UL700, which makes it much more durable.Four years have passed since developing Jack Supports using high-strength steel and improving them to meet the needs of the market. The market looks stagnant, but its trend is changing fast. That’s why we can’t just sit still in the lab and make an experiment to develop products.In that sense, the Hybrid Jack Support is the result of POSCO and its client going back and forth between the lab and the field, constantly thinking about ideas to overcome the weaknesses of the product. In the second quarter of this year, it was listed as one of the INNOVILT certified products as well.The temporary materials market is a place with unclear quality standards and a high temptation of low-cost goods. However, it is our mission to change this perception and eliminate the blind spots for the safety of workers with our products and technologies. At the same time, we should create solutions that can bring substantial benefits to the constructors as well. This is the reason why, even today, INNOVILT Lab is busy developing new solutions. INNOVILTINNOVILT LABTemporary MaterialTemporary WorkUL700UL700 Hybrid Jack Support
[INNOVILT LAB] #3 Say Goodbye to Heavy Scaffolding, Meet Hybrid Jack Support
[INNOVILT Alliance Journal] ⑤ Jooshin Co., Ltd., a Manufacturer of ZintaMax
Join POSCO Newsroom for its next story of INNOVILT Alliance Journal! The fifth story is about the visit to Jooshin Co., Ltd., a manufacturer of ZintaMax.Finishing materials are used to complete the exterior part of a building. They serve to enhance the aesthetic features of the building as well as protect the surface from external impacts. The materials are categorized into interior and exterior material, roofing material, etc., according to their usage. Since finishing materials are exposed — thus visible and touchable — unlike structural materials, the context of a building can vary depending on which finishing material is used.Jooshin Co., Ltd. specializes in producing and selling finishing materials optimized for various purposes, such as for exterior walls of buildings, interior, roofs, and so on. Founded in 2001, the company has worked on product development continuously and, as a result, grown into a small giant with more than 40 patents today. Behind the impressive performance, CEO Myeong-Woo Yoo’s management philosophy, change and innovation, lies.▲ CEO Myeong-Woo Yoo explaining the management philosophy of Jooshin Co., Ltd.“Jooshin does not develop a product unless a patent is a prerequisite. It means that we focus only on high value-added products that go beyond conventional products with new non-existent ideas. The conditions in the market change from day to day and demands from clients are becoming more challenging. That is why Jooshin aims to create new trends by grasping and responding to market changes.”The persistent efforts did bear fruits. Currently, Jooshin Co., Ltd. stands out as a company leading the top 1% of roof and exterior market in Korea. In 2016, the company developed roof and exterior materials that adopt POSCO steel plate and SUPER ALCOSTA, a highly corrosion and heat resistant aluminum plated steel plate, and participated in major public projects, such as the Pyeongchang Winter Olympic Stadium and Incheon International Airport. At the beginning of this year, seven of the company’s products were selected as POSCO INNOVILT products. As a result, it has become a single company with the most INNOVILT products. Among them, ZintaMax, the main product of the company, is the subject today.

l ZintaMax, The Beauty Imposed by Variations of Straight Lines

ZintaMax is a block-shaped finishing material that stretches out in a straight line. It can be installed on the exterior and interior walls of the building, on the ceiling, and all other places, excluding the roof. Since each finishing material has different strengths and employs different construction methods depending on where it is adopted, there aren’t many products that can be used for multiple purposes. On the other hand, ZintaMax is highly versatile as it can be installed anywhere a finishing material is needed with high strength and simple construction method thanks to PosMAC, its raw material.Then what about the design? At first glance, you might think that simple straight lines and curves are all about the product, but many different kinds of design can be created by using ZintaMax. Its sizing can be flexible to fit for various purposes. For example, if you drill a hole and install it with lighting, it transforms into a decent interior material.PrevNextAnd this is not all. By utilizing the color printed steel product, which is a trend in the market these days, it is also possible to produce ZintaMax in diverse colors and patterns, such as yellow, blue, wood, and marble. POSCO’s PosMAC, the raw material of ZintaMax, goes under surface treatment at POSCO C&C and is then sent to Jooshin to be fabricated into the product. POSCO’s Jin-Ah Kim explained, “The color printed steel of POSCO C&C embodies the features of other materials almost perfectly so there is little difference in appearance from actual wood or marble. It is an eco-friendly material that can realize the interior and exterior desired by clients without damaging nature.”PrevNextAnother thing, with POSCO C&C’s Multi-Color Steel Sheet, more diverse designs can be created. Multi-Color Steel Sheet is a color steel product where multiple colors can be expressed simultaneously on a single-coil, and POSCO C&C is the sole domestic manufacturer. POSCO’s Jin-Ah Kim said, “When ZintaMax is made with these Multi-Color Steel Sheets, all the colors of the convex and concave parts can be expressed differently. The distinct and specialized design can satisfy the diverse needs of clients.”PrevNext

l Design, Safety, Durability: 3-in-1!

ZintaMax, an innovative item in the conventional metal finishing material market, was born through collaboration between Jooshin Co., Ltd., and POSCO. While carrying out a joint study in 2019 regarding steel construction materials, Jooshin Co., Ltd., POSCO, and POSCO C&C came together to develop a finishing material with a unique design. Jooshin invested in facilities for production, while POSCO and POSCO C&C developed new colors and designs for the products. “No matter how good silk is, it can not be called a garment without proper altering. The case is the same here. Excellent products like the multi-color steel sheet and PosMAC will truly be acknowledged only when there are practical technologies to apply to buildings. POSCO and Jooshin worked on the details together, and ZintaMax is the result.”Finishing material should be safe as well as aesthetically pleasing. How strong is ZintaMax against external stimuli, such as fire or corrosion? CEO Yoo proudly explained, “ZintaMax does not burn in fire and also has aesthetic features as well. These days, the incombustibility of finishing materials, like the roof and exterior materials, is being emphasized due to a series of fires that broke out in warehouses. Relevant laws have also been revised, banning the use of flammable finishing materials in buildings above three floors. ZintaMax is safe to use because it is made of POSCO C&C incombustible colored steel that does not ignite at high temperatures and generate less smoke and harmful gases.”Since it is made of POSCO steel, the finishing material is also highly resistant to corrosion. “PosMAC, the raw material of ZintaMax, has a stronger plating layer than conventional galvanized steel, so it is highly wear-resistant and scratch-resistant. Generally, the cutting surfaces or parts that are scratched during installation gather rust. However, PosMAC has an oxide layer called Simonkolleite made by plating zinc with magnesium and aluminum. This layer prevents the corrosion of the surface as well as the machined parts.”

l INNOVILT ZintaMax: How Are They Made?

PrevNextThe aesthetic yet safe and durable ZintaMax. How is it made? The entire process was walked along with an explanation from Jae-Wook Yoo. He said, “The manufacturing process of ZintaMax is largely divided into three stages. The large steel coil that you can see over there is color printed steel made of PosMAC. POSCO’s PosMAC is coated at POSCO C&C and delivered here to Jooshin in coil shapes. The coil-shaped steel sheets go under an Uncoiler to make them flat. Next, they pass through the forming roll where they are shaped into desired forms. When they are put into the roller, the bumpy shapes of the ZintaMax are complete.” The manufacturing process was as simple as its construction method. The shortened construction period could also help reduce cost.<span data-mce-type="bookmark" style="display: inline-block; width: 0px; overflow: hidden; line-height: 0;" class="mce_SELRES_start"></span><span data-mce-type="bookmark" style="display: inline-block; width: 0px; overflow: hidden; line-height: 0;" class="mce_SELRES_start"><span data-mce-type="bookmark" style="display: inline-block; width: 0px; overflow: hidden; line-height: 0;" mce_selres_start="">?</span></span>What is unique is that most of these processes are performed directly on site. It is a differentiated part from general finishing materials that are transported to the construction site after making finished products at the factory. Director Yoo Jae-wook said, “Because we look at the building to be applied in the field and make it right away, it can be constructed without any length limitation.”

l You Can See ZintaMax Here!

Buildings adopting ZintaMax can easily be found around us. Starbucks, the mega-franchise coffee shop, is an example. The recent Starbucks coffee shop that opened in Gimhae adopted a wooden pattern ZintaMax to the front of its exterior wall. On the outside, it looks just like wood. “If the walls were made with real wood, the processing cost would have been high, and there must have been a fair amount of logging.” On the side and back walls of the coffee shop building, a dark-gray zinc pattern ZintaMax was applied. The entire building demonstrates the attractive features of the color printed steel sheets that can embody all materials and colors without any restrictions. The charms of ZintaMax can also be seen in other various buildings, including the Gwangyang POSCO Childcare Center and the Sharp Gallery in Seoul.PrevNextExport prospects also look bright. Jae-Wook Yoo said, “We have received positive responses from Southeast Asian clients for suggesting wooden patterned ZintaMax. ZintaMax, which has both the durability and design features of steel, will serve as a definite alternative in Southern Asia where the deformation of construction wood is frequent due to hot weather.” He also added, “Although all discussions have been temporarily suspended due to the COVID-19 pandemic, we expect tangible results soon.”

l Jooshin & POSCO, “Standing Out by Working Together”

If there is a single word that binds Jooshin and POSCO, it would be “First Mover”. Jooshin has been expanding the use of not only PosMAC but also PosPVD, a next-generation surface-treated steel plate developed by POSCO, in the steel construction material market. Regarding the cooperation between the two companies, Jae-Wook Yoo stated, “Working with POSCO Group, I could feel the passion that the entire group has for developing new products. They are eager to lead the market and do not hesitate to try out different attempts. Just like a pioneering leader. Such features fit well with the identity of Jooshin, which is to pursue creativity and innovation.”Jin-Ah Kim also responded, “Whenever we find clients who are worried about how to construct with colored steel, we show them ZintaMax. ZintaMax is proactively applied to projects of POSCO E&C, and so it is not an exaggeration to say that it is growing together with POSCO Group. Jooshin always stimulates us with new ideas making us wonder where else we can use POSCO products in such a variety of ways.”With the INNOVILT Alliance, the synergy shown by the two companies is expected to expand further. Both companies are working together on the R&D of a louver* with non-flammable performance. Conventional wooden louvers are flame-retardant, but not non-flammable, so if this collaboration is successful, a safer louver can be introduced to the market. *louver: interior wood material used to prevent glare.CEO Myeong-Woo Yoo commented that INNOVILT Alliance is a strategy of going together. At the end of the interview, he said, ”I’m excited for POSCO’s challenge to create a new structure with partner companies. Though the way of going together might not be easy, I am looking forward to the future that Jooshin and POSCO will create together.”※ This content was produced in compliance with the COVID-19 quarantine guidelines before ‘Social Distancing Step 2.5’ was imposed. INNOVILTINNOVILT AllianceINNOVILT Alliance JournalJooshinMulti-Color Steel SheetPOSCOPOSCO C&CPosMACZintaMax
[INNOVILT Alliance Journal] ⑤ Jooshin Co., Ltd., a Manufacturer of ZintaMax
[INNOVILT Fantasia] #5 Urban Hive: An Innovative Architecture Created by Smart Beams
Urban Hive, known for its unique appearance which features many round holes, is an office building constructed 13 years ago. Designed in 2004 and completed in September 2008, it is a 17-story building with a site area of about 1000m2 and a building area of 585m2.Seoul, the capital of South Korea, is a fast-changing city. Everything changes quickly including popular places to go where people tend to gather. The location of the Urban Hive is also quite notable. Before Sinnonhyeon Station (Line 9) was built, the adjacent area around the Urban Hive wasn’t all that impressive. At the time of the building’s completion in 2008, Gangnam Station — the nearest subway station then — had just exits 6 and 7 (currently expanded to exits 10 and 11), which meant that the building was located quite away from the downtown area. The block where Urban Hive stands served as a small place for people to enjoy the nights of the city at restaurants and bars hidden amongst low-rise residential buildings.Architect In-Chul Kim said that the design of the building started from the bustling vibes of Gangnam. He explained that his perspective was to calm down and relax the hustle and bustle of the city. Kim adopted a simple cube form in the building structure, which was a “movement to capture the atmosphere of the city”. However, the intended simplicity did not end with just the box-shaped design. It came to light through a unique concept and structure that reversed the inside and outside.

A Straightforward Structure on the Outside

The outer concrete wall, which has about 3,300 circular holes with a diameter of 1m, is a kind of bearing wall that supports the structure of the building. This is quite different from the conventional high-rise buildings where reinforced concrete columns are covered by layers of glasses and metals outside. Architect Yoon-Gyoo Jang exclaimed, “Since middle and high-rise buildings in cities mostly adopt the conventional method of applying curtain walls, the case of Urban Hive is quite exceptional. It has become an example which proves that the exterior of a building can be structured and it can be an element constituting the entire elevation.” Put simply, it means that the concrete walls of the Urban Hive weren’t built to cover up or block something. It is purely an indispensable core put in place to support the entire structure.PrevNext

Constructing a 17-story Exposed Concrete Building

Constructing a building of this size and height with concrete entirely is a rare case — even globally. This is due to the recent trend in modern architecture which is to capture a sense of lightness and openness in shape and materials. Other than that, there is a structural issue as well. The higher a building is, the heavier the reinforced concrete becomes, making it difficult to support the overall weight. Additionally, it is difficult to smoothly treat large surfaces of exposed concrete without other decorations because it causes a concern of rough or poor finish.Chang-Nam Lee, CEO of SEN Engineering Group, who participated in the structural design, explained that there were multiple discussions at the beginning, such as whether to use factory produced precast concrete or on-site concrete, and whether to use permanent molds to shape the holes on the wall or whether to form them into different shapes like a diamond shape. Reducing the possibility of cracks, which is a weakness of concrete, was another important factor to consider. Lee said, “The architect wanted the wall to be exactly 40cm thick. If it became thinner than that, the depth of the holes on it would be reduced, giving it a poor look. The architect was also against making the wall thicker or using a separate finishing material.”Would a 40cm-thick exposed concrete be able to act as a bearing wall to stand the load of a 17-story building? The width of the interior space is 17.35 meters. This means that there is space to add a column in the middle. However, neither the architect nor the structural design team chose the easy way. They stuck to the initial design. They chose TSC Composite Beam as material for the wall so as to build a bearing wall without any columns which would secure the usability and openness inside as well.

[Architect’s Pick : INNOVILT TSC Composite Beam]

TSC composite beam is composed of steel outside and concrete inside, which is slightly different from the conventional method where reinforced concrete surrounds the steel inside. It is constructed by filling concrete inside the mold made of steel plates. Adding rebars inside is possible, but this isn’t the case at most sites, including the Urban Hive. The composite beam consists of a web made of cold-formed steel plate, upper and lower plates, and inner concrete.The typical reinforced concrete consists of molds, rebars, and concrete. Among them, the molds are temporary materials needed just during the construction. However, they take up a large portion of the expense and make the construction period longer as well. The number of technicians who assemble the molds is also decreasing, therefore, increasing labor cost. How could this problem be solved then?TSC composite beam combines steel plates and concrete, becoming a new concept of material, free from molds and rebar. Compared to reinforced concrete beams, it has a smaller volume, yet less bending and deflection. The lower steel plate supports the structure in the tensile direction, preventing cracks. The amount of steel frame is minimized while long-span construction becomes possible. The construction period is similar to or shorter than that of steel-framed buildings and costs less. Another feature making the material suitable for urban structures, such as the Urban Hive, is that it is lightweight. Smaller tower crane capacity is an additional bonus.Modern architects contemplate for interior space without columns. If you are wondering what makes the TSC composite beam, built to reduce the columns in the interior space, so different, think of it this way. Suppose that there is a building that has an outer wall with holes like cheesecake and the same floor composition. What if this building has a column at the center of its inner space? All architectural concepts would be in vain. When a column is needed for the structure, the outer wall becomes a decoration once again. It no longer embodies the idea of the architect — a small but complete difference.PrevNextUrban Hive has been a hot topic for its exterior, but it is the interior that actually brings the architecture to life. Using TSC composite beams, the span is able to reach 17.35m long without a column, and the height of the beam stands at 60cm. All of this was accomplished with a cost reduction of 30% compared to the conventional steel composite beams. Between the outer wall of the Urban Hive and the glass wall of the offices is a space for outdoor air. The round holes on the wall are also hollowed out except for areas under the waist where acrylic plates are placed. The architect wanted to provide each floor with long corridors as spaces where outdoor air could flow. The building doesn’t have a separate lobby but there is a cafe on the first and second floor where people can access the building more easily and comfortably. At the cafe, you can see the TSC composite beam on the ceiling, because it is deliberately exposed without additional finishing materials.
[INNOVILT Fantasia] #5 Urban Hive: An Innovative Architecture Created by Smart Beams
[INNOVILT Fantasia] #4 A Twisting Stack of Layers: The National Assembly’s Communication Hall

A New Communication Hall for Press Coverage, Located Next to the Green-domed Main Assembly Building

A new addition to the Republic of Korea’s National Assembly complex building was completed late last year. Recent press conferences held at the new Communication Hall have brought the building into the public spotlight. The project began as a solution to two pressing problems: the National Assembly complex required more workspace and waiting rooms for government officials, as most of South Korea’s government branches have moved their offices to Sejong City, and expansion of pressroom space, as a growing number of journalists and media outlets demanded.PrevNextThe National Assembly complex is built on around 330,000m2 located at 1 Yeouido-dong, Yeongdeungpo-gu, Seoul, South Korea, home to 12 buildings in total, including the National Assembly Building, a Member’s Office, and a Library. The main National Assembly Building is a structure of 7 stories and one underground level that opened in 1975. Visitors who enter the main gate and walk across the lawn plaza are greeted by the Assembly Building with its gigantic colonnade and its majestic 1,000-ton steel-framed dome. To the west of the Assembly Building is the newly built Communication Hall.

A Design Featuring Twisting Stack of Individual Layers

We are now living in an era of mobile communications and Ubiquitous Internet connections in which anyone can express their complaints anytime, anywhere. What concept would have been the most appropriate for the new facility that was to replace the aged Welfare Hall? At the time the original project was announced, its design competition guidelines, themed around “Communication”, specified the design for a “symbolic smart office facility and press center” with a “high level of flexibility to meet the ever-changing needs of the society.”A simple square shape was the design the winning architect decided on, choosing to honor “the formal monumentality of the current National Assembly complex.” Utilizing the existing order of the complex in the design of the new building, the decision proved to be wise. The 4-story facility has a total floor area of 24,732m2 with a straightforward space arrangement designed following the project guidelines’ office space and pressroom requirements. The Press Center and the Smart Work Center are located on the 2nd and 3rd floor respectively. There is an underground parking space, a cafeteria, and a shop on the ground floor, as well as offices on the 4th. According to the architect’s explanation, the division of functions by level was “to keep each floor independent to make more efficient use of office space and provide a productive work environment.”As evident in the slight rotation of each floor, the design is much more dynamic than those seen in typical “boxy” building designs. From the outside, the building looks like a twisted stack of floor-plates, revealing exposed rooftop spaces which are then used as terraces that can be accessed with ease from the inside of the building. There are ample common areas, small and large, for short breaks and conversations, and the large central atrium incorporates green space into the structure. Four core areas surrounding the atrium divide the flow of press members, government workers, and the general public. In and around the building, the overall design gives a great sense of openness wherever you are.

[Architect’s Pick : AU Beam, D-Deck, ES-Column]

The AU Beam, a POSCO INNOVILT product, was applied in the simple and spacious Communication Hall building. The AU Beam is a composite beam made of an A-shaped steel anchor cover on top of a U-shaped lower steel plate filled with concrete. The steel beam’s slim structure, with a depth smaller than that of a typical concrete column, allows greater floor height. Despite its smaller size, The beam ensures an increased rigidity thanks to the composite action of steel and concrete. AU Beam acts as a fit for purpose solution to the problems of bending and deflection that tend to occur in long-span designs with fewer columns and walls. Unlike the widespread practice of building a stud bolt between a slab and the top-end of a steel beam on-site, the AU Beam system, with its steel anchor also functioning as a connector, is easier and faster to install.Another one of the latest construction technologies applied in the Communication Hall building is the D-Deck. D-Deck, a construction method designated as Korea’s New Construction Technology in January this year, uses an inverted-triangular-shape wire girder and a deck with two ribs. The girder is placed on the lower-part between two ribs of the deck which is made of steel plate. The wave-like shape of the deck, whose section looks like a series of camel’s humps, provides better strength preventing any potential deflection or deformation of the structure while allowing designs with fewer beams and longer spans. While the reinforced concrete deck can be installed up to 4m long without beam, the D-Deck can be installed alone up to 6-8m. The construction work is also straightforward and does not require welding – simply positioning the girder on a spot between the two ribs is enough.PrevNextThe third feature of the project is the use of the easy-to-construct and earthquake-resistant ES-Columns instead of the more broadly used H-beam or reinforced concrete columns. The ES-Column made of POSCO’s high-end earthquake-resistant steel is a composite column system that consists of a structural steel tube within a concrete-filled square-shaped steel pipe, bringing the total amount of steel used down to a minimum and offering better shock and fire resistance.The fact that no complaints were brought against construction costs is a testimony to the economic feasibility of INNOVILT construction materials. The INNOVILT products were applied in building the Communication Hall in order to minimize the workload at the construction site while providing improved levels of stability and shorter construction time at a lower cost.Open spaces in and around the Communication Hall are expected to be enjoyed by all citizens once the current COVID-19 crisis is over. Creating an abundance of delicate spaces, the new facility is a successful design that blends the 70’s architectural theme of the National Assembly Building with the innovative steel construction technologies of today.
[INNOVILT Fantasia] #4 A Twisting Stack of Layers: The National Assembly’s Communication Hall

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