Worthy of Remembrance
The design, engineering and construction of the Missouri Korean War Veterans Memorial
By: Mitch Bloomquist | Tilt-Up Concrete Association
Each year, the Tilt-Up Concrete Association (TCA) selects a new location for its Annual Convention. Last year, Irvine, California was selected and Amelia Island, Florida will host the event in 2012. This year, the TCA selected the heart of this great country, in Kansas City, Missouri. This presented an opportunity for connecting and working with members on a level they never had before, applying the Tilt-Up construction method in a way that it is not traditionally thought of and contributing to a community and a moment in history worthy of remembrance.
As an international non-profit trade organization the TCA often cannot invest significantly in any one community or region. However, the members of the TCA indeed are imbedded in their respective communities and through the members throughout greater Kansas City, an interest in demonstrating the uniqueness of Tilt-Up while offering something to the community itself was identified. A decision was reached by the TCA Board of Directors to create or discover a project through which the TCA and its members could execute and donate to some local organization, charity, or the city itself.
One of the most exciting aspects of the idea was the opportunity to challenge the local TCA members in the area and let their community know more about the kind of people they are and the quality product and services they provide.
Multiple projects were considered including a house for Habitat for Humanity, a bus stop, a park pavilion, etc. It was decided that the project that offered the greatest potential for flexibility and visibility was a park structure that would be donated to the city following the annual convention. At this point TCA staff turned to a local resource, Christy Martin, Executive Director of the Concrete Promotional Group of Kansas City. Martin then contacted Jimmi Lossing with the Kansas City, Missouri Parks and Recreation Department in search of a project. This set in motion a timetable and a project challenge that few imagined possible but all were convinced should be attempted.
On April 1, 2011 Lossing suggested the possibility of working with the Missouri Korean War Veterans Memorial Commission. She stated that they had land, that they needed a memorial and that they may be interested in what the TCA was offering. Lossing also conveyed that the MKWVM had found difficulty in identifying a design or scope that could embody the remembrance that they aspired to deliver within a budget they could provide.
Less than six months separated this date from the opening of the 2011 TCA Annual Convention, yet the TCA committed to the project and began working on a schematic design. Within two weeks, Mitch Bloomquist, Project Manager for the Tilt-Up Concrete Association presented the Missouri Korean War Veterans Memorial Commission and the Kansas City, Missouri Parks and Recreation Department with a design proposal. It was well received and after the incorporation of a few requests, the design rapidly moved from schematic design to engineering and design development and a project team was quickly assembled.
Local TCA professional engineering firm member Needham and Associates, Inc. of Lenexa, Kansas was asked to serve as engineer of record for the project and graciously offered their services pro bono. Simultaneously the TCA approached a local TCA contractor member, Summit Concrete of Lee’s Summit, Missouri, about building the memorial. They too accepted the challenge and likewise offered to contribute their services. The amount of support given by these two member companies from the very beginning of the project was instrumental in moving the project forward. Without their commitment and good will the project would have gone no further.
As the project continued to increase in scope and complexity the Missouri Korean War Veterans Memorial Commission hired JE Dunn to serve as general contractor. JE Dunn followed suit and offered to provide their services at no profit. On June 8, 2011 the project team met for the first time in Kansas City at JE Dunn’s office. With less than 4 months to go, there was no time in the schedule for any missed steps.
The TCA and Needham and Associates moved ahead with construction documents.
Various factors, including the approval of concrete sample panels, delivery of images to be embedded in the memorial (to be used in the creation of the form liners), and fundraising efforts delayed the start of construction a few weeks and threatened to jeopardize the planned dedication ceremony which had already been published.
On July 27, 2011 the project received the notice to proceed and construction started, just two very short months before the opening of the 2011 TCA Annual Convention and the dedication of the memorial. As it would happen, the date set for the dedication surreptitiously coincided with a special day marking the arrival of American troops in defense of South Korea. “In Korea the day is celebrated still,” said Young Kim, A Korean-American and friend of Jim Shultz, Co-Chair of the Missouri Korean War Veterans Memorial Board of Directors. “It’s called Ku Yi Pal Su Bok in Korean, or September 28th, Recapturing Seoul.”
As with any work of architecture, this project is an addition to a dynamic context. The project is inserted into an already established built fabric, a continuous narrative, and the preconditions of each visitor. Its presence alters ones experience not only of Washington Square Park but also of the process of recalling memories. In return, it is affected, and will continue to be by the continuous development of its physical context and the variety of people that visit it.
Space flows freely in and out of the memorial from multiple directions but is slowed and concentrated within the structure. The memorial wraps each visitor in a defined space dedicated to the remembrance of those who served.
Each element of the structure is encountered individually, first the ground, then a wall, the roof and then another wall. While each element is separated in time, they collaborate to offer both the security and friendliness of transparency and openness, and the comfort and focus of enclosure. The effect is a perceived interior and exterior. This perception, with the scale of the memorial, encourages an intimate interaction with the content within and has an affect on the pace with which the memorial is experienced.
Perhaps the most meaningful role of the memorial is that it lends a haptic encounter to an otherwise intangible memory. It is a place.
Formally, the memorial is a composition of a symbol representing the individual and an action representing their act.
The chevron, a simple geometric shape, is often used to identify individuals serving in the armed forces. Depending upon the country and service, the graphic is multiplied and or altered to signify rank, branch, etc. But in all cases it is tied to the individual. The memorial, in elevation, can be read as a section of that symbol representing the piece of each individual that is present in spirit at this place.
The twisting form of the memorial is inspired by various aerial dogfighting maneuvers practiced during the Korean War. A “dog fight” in military terms refers to air-to-air combat to establish air superiority over the battlefield. Fighter aircraft are designed for such combat involving various evasive maneuvers and tactical approaches to counter those of the enemy. In the Korean War the first real air-to-air combat between jet powered aircraft took place between USAF and planes of the North Koreans most often supplied and piloted by Russian and Chinese forces. The increased speed of the aircraft and new armaments made the combat very swift and new maneuvers developed.
While this is only one component of a much larger effort, it encapsulates the action not only of the pilot, but that of the persons involved in creating the technology, the support surrounding the operation, and the enduring influence of the advancements in technology, individual skill and strategy.
Together these two guiding concepts represent the individual and their actions. The fact that they are more than their service, that they are part of a greater family and community, and that they took action on something that they believed in, be that the issues surrounding the war or serving their country unconditionally.
Beyond the programmatic elements of the project associated with the remembrance of those who served in the Korean War, the project was charged with demonstrating the versatility, applicability and beauty of Tilt-Up concrete construction. These efforts can be seen in the exploitation of the inherent benefits of Tilt-Up.
The articulation of the edges of the Tilt-Up panels and the use of them to mediate between the horizontal and vertical planes of concrete not only highlights the effectiveness of manipulating the one formed edge of a Tilt-Up panel, it aids in the reading of the overall form as a continuous ribbon.
The outside faces of the memorial were treated with a retardant prior to concrete placement in order to expose aggregate on the surface of the panel. The result is a texture that is familiar and one that gives depth to the surface. The interior of the structure and all of the edges were polished. This treatment reinforces the relationship between interior and exterior and also addresses the formality and monumentality of the content within.
Openings in the walls and roof break-up the mass of the large panels and aid in the composition of interior elements as well as provide additional layers of light and transparency. Reveals in the surface of the panels on both the interior and exterior reinforce the geometry of the structure and again aid in reducing the scale of the panels.
Large stainless steel plaques inscribed with over 900 names of those from the State of Missouri who paid the supreme sacrifice and gave their lives in defense of South Korea are inset on the interior of the structure. On the exterior of the memorial two large images, one on the outside face of each wall, are cast into the concrete. Grooves of varying depths and widths affect light cast on the structure to reveal the dynamic images. Their appearance changes with the light and viewing angle affording visitors a variety of experiences, becoming an interactive element of the design.
In panel design theory, the engineer typically designs the vertical column strip assuming that the panel acts like a one way flexural member using slender wall theory. This project, however, had very few vertical load paths. To account for the unusual load paths, Needham’s Karen S. Hand, P.E. designed reinforcing in four planes, two vertical, one horizontal and one plane at a 45-degree angle. The first analysis was done using only the vertical strips but the nature of the roof loads and shape of the panel left the overall design difficult to grasp. In order to finalize the design and determine how the panels would behave, Hand built a finite element model in STAAD (a structural analysis and design software). This allowed her to look for the stress risers in the panels to accommodate for the odd geometry and reinforcing load paths. Hand noted, “This project was the most geometrically complex project I have ever worked on.”
The structure has only two parallel wall panels so the lateral in-plane loads are resisted by fixed base connections. To ensure extra stability of the panels, special heavy-duty base connections were used. The panel was designed with outrigger “feet” to increase the moment arm and keep the panel more rigid than the standard fixed base connection. These were placed at 2’-0” on center and welded to a large embed cast into the footing. This also insured that the connections were robust enough that temporary bracing could be removed prior to the erection and placement of the roof panel. This was essential in the sequencing of the project as the flatwork around the panels and finished grading needed to move forward while the roof panel was being finished.
Needham detailed the steel embedment items as well. The roof connections went through several design iterations but ultimately a shelf connection was used. Deformed bar anchors in lieu of headed studs welded to plates and channels provide a substantial strength in the design of the connections. Tincher’s Welding, of Harveysburg, Ohio fabricated the embeds and personally delivered them to Kansas City.
The lifting and bracing design of the project was done by Scott Collins, P.E., Assistant Chief Engineer for TCA sustaining member Meadow Burke. The complex geometry of the panels made the lifting design especially difficult. The panel geometry caused the panels’ center of gravity to shift drastically to one side; this was remedied using special crane rigging to re-balance the lift points back onto the panels’ center of gravity.
With only two months to build the memorial, Summit Concrete was asked to do the impossible.
Due to a continuous string of events occupying much of the space around the site of the memorial in Washington Square Park and the foundation work being performed concurrently with the construction of the panels, the decision was made to cast the Tilt-Up panels on recyclable casting slabs located in Summit Concrete’s nearby yard. Casting slabs are utilized in many projects for various reasons, typically because of a lack of slab space due to the ratio of wall to floor area.
The process of forming the panels was complicated.
The overall shape of each of the three main panels (2 wall panels, 1 roof panel) was a parallelogram with 45-degree angles. However, the two faces of the panel were designed to be misaligned. At the bottom of the panel the faces were offset 8-inches in one direction and at the top 8-inches in the other direction. The edge of the panel in-between the two faces was to be triangulated creating a faceted edge. All of this was done within the 8-inch tall edge forming; the faces of the panels were flat. This is typical of most all Tilt-Up concrete construction. The way in which the edges were designed and formed however was not typical.
Because of the manner in which each panel interacted with the next, there was virtually zero tolerance and the schedule did not allow for any mistakes. Roger Meyer, Tony Turner and others from Summit Concrete began forming the panels and realized quickly that the angularity of the form coupled with the faceting of the edges created conditions that were not simple to construct. Bloomquist traveled to Kansas City on multiple occasions to assist in interpreting the form, working out the forming details and making adjustments to the design as needed to best utilize the advantages Tilt-Up offered.
Many pieces of the project however were already set into motion and the panels would have to accommodate pieces such as plaques and signage rather than field measuring altering the design of those elements, a unique condition for most projects Tilt-Up approaches.
ShadowCast form-liners used to cast the images in the exterior faces of the panels were fabricated and donated by Innovative Brick Systems of Denver, Colorado. In order to have these liners in place so that the panel would be ready to pour on time, Mike Denson pushed the capabilities of their facility to the max and turned them around in just days. To create the liners, photographic images were carved into a wooden “tool” or mold using a CNC milling machine. Each mold was then used to create the elastomeric liner. Innovative Brick Systems was able to create the very large, one-piece liners. They were incredibly durable and easy to work with and fortunately fit like a glove into the areas defined by reveal strips that wrapped the image and were already in place.
Once the first wall panel was formed, including reveals, insets and embedded images, Summit began to place the reinforcement. The reinforcement layout was incredibly dense and the support of the extremely heavy custom imbedded structural elements was to say the least, tricky. At this point, it was realized that because of the complexity and density of the reinforcement layout coupled with the size and weight of the structural embeds, the plan to tie it all together and remove it in one piece in order to apply the retardant to the slab would have to be reconsidered. Additionally, the angled edges and openings would prevent anything from coming straight up and out and any effort to remove the assembled structural mat would require additional time and reworking.
The decision was made to apply the retardant to the slab with the reinforcement in place. This was tedious work but an alternative had not presented itself.
Hardware to accommodate last minute modifications to the lifting design was rushed to the site courtesy of White Cap Construction Supply, the Meadow Burke distributor in the Kansas City area, who contributed the hardware and other rental items at no charge.
Once everything was in place, a final layer of insets and reveals to be cast on the top face of the panel was secured to the top of the forming and the panel was poured.
On a traditional Tilt-Up project, the next step would be to lift these panels in to place. On this project however the design called for the inside, or top side, of each panel and its edges to be polished. Summit Concrete got a crash course in polishing from Bledsoe Rentals, the company providing the equipment, and they began to work the surface of the panel. After hours and hours of work, Summit had a new appreciation for the time and skill it took to produce a polished concrete wall. Roger Meyer and Tony Turner spent days, nights and weekends working on the panels to stay on schedule. Scott Collins noted, “Never in my experience, have I seen the level of commitment to a trade organization or an industry than that of what Roger Meyer and Summit Concrete has put forth.”
Once the panels were to a certain point, they were lifted onto a steel frame where they were situated vertically so that work on polishing the edges could begin. They were then transported to the site on this frame in the vertical position and lifted into place.
What started as an effort to demonstrate the benefits of Tilt-Up concrete construction quickly turned in to something so much more. Not only is this project a testament to the versatility, applicability and beauty of Tilt-Up construction, it is a demonstration of the generosity, pride and good will of TCA members. Most importantly, it continues the legacy of Korean War Veterans and recognizes those who paid the supreme sacrifice and gave their lives in defense of South Korea.
The TCA and its members provided products, professional services and labor at absolutely no cost. Additional contributions to the project came from the city of Kansas City, Missouri, private donors and other local companies.
Tilt-Up Concrete Association (TCA) – Architectural Design, Member Coordination – Mitch Bloomquist, Project Manager
And TCA Members:
Needham and Associates, Inc. Consulting Engineers – Structural Engineering – Karen Hand | Jeff Needham – Also providing reinforcing steel through their steel division, Design Build Steel (DBS)
Summit Concrete – Tilt-Up Panel Construction – Roger Meyer | Tony Turner
Innovative Brick Systems, LLC – Form-liner for Embedded Images – Mike Denson
Meadow Burke – Lifting and Bracing Design and Hardware – Mike Wolstenholme | Scott Collins
Tincher’s Welding – Structural Embed Fabrication – Terry Tincher
White Cap Construction Supply – Lifting Inserts, Equipment – Dale Fuhrman | Anthony Callura
With support from the Concrete Promotional Group (CPG) – Christy Martin, Executive Director
Dunn Project Solutions – General Contractor – Bill Dunn | Mike Slattery | Lynn Newkirk
Lafarge A&C – Concrete for Tilt-Up Panels – Dale Eason | John Caldwell | Chuck Cox
PROSOCO, Inc. – Graffiti Guard
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