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State-of-the-art concrete docks at Wangsan Marina in Incheon, South Korea, are setting a new standard for marina development in the region.
Marina Development in South Korea
Incredible surroundings, increased economic wealth, and a safe and secure social environment make South Korea an intriguing market for the boating and marina industries. During the last decade, a great deal of effort has been placed by the government as well as private investors on improving the region’s boating infrastructure. However, the country’s weak sailing culture and lack of experience in the construction and management of modern boating facilities has been a major hurdle in moving the industry forward at a faster rate.
Albeit slow, progress is coming. The opening of Wangsan Marina, a contemporary boating facility in Incheon, South Korea, is opening the door to boating for many Koreans who did not have the opportunity before. Prior to the opening of Wangsan, there were no large scale marinas in or around Seoul’s major metropolitan area. With 266 moorings and a dock facility on par with the world’s most modern marinas, Wangsan is expected to have a major impact on the market and be a key force in setting a new standard for boating facilities in South Korea.
The concept for Wangsan Marina was to build a start-of-the-art competitive sailing venue for the 2014 Asian Games that could later serve as a public marina with amenities and services that would cater to domestic as well as international boaters.
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The Unifloat concrete floating dock system from Bellingham Marine utilizes a waler system to connect individual float modules together.
Walers are structural beams mounted flush to the deck of the Unifloat concrete floating dock from Bellingham Marine. They attach to the float by long rods threaded at the ends. Called “through rods,” they span the width of the float and are held in place with washers and nuts.
Walers can be made of a variety of structural materials depending on the engineering requirements of the marina. These include structural timbers, composite materials, steel and other materials. The vast majority of Unifloat systems employ structural timbers although Bellingham Marine has built marinas with walers of other materials as appropriate to the project.
Concrete floating dock marinas are manufactured and assembled in modules. Modular construction allows bending at the float connections to provide flexibility appropriate to a structure on water subject to wave action. In addition, the manufacture and installation of the docks is more manageable when floats are cast and transported in modules. A further benefit is that modules can be removed and replaced; in the unlikely event that this is necessary, individual modules can be disassembled and modified as needed.
The vital structural purpose of the walers is to connect the float modules. In a Unifloat marina, no other connection method, such as hinges between floats, is necessary, or in fact desirable, as the waler system has proven itself under the harshest tests nature can deliver. Walers perform two other functions. First, they protect the concrete floating dock from impact from a docking boat. Secondly, they present a gentle surface to the hull of a boat using the moorage, especially when the walers are built of structural timbers and when combined with protective rub rails.
The birth of the waler.
The modern Unifloat waler system is the direct descendent of the waler-connected concrete floating dock concept patented by Ernest M. Usab of Long Beach, CA, on October 28, 1958. Usab was awarded U.S. Patent 2857872 and licensed it to Bellingham Marine the same year. Bellingham Marine introduced the technology to the world for the manufacture and construction of Shilshole Bay Marina in Seattle, Washington. In the following years it became apparent that Usab’s concept would revolutionize the marina industry and Bellingham Marine bought the patent.
Since that first project, Bellingham Marine has continuously improved the technology and has now manufactured and installed more than 20 million square feet of docks in tens of thousands of installations worldwide. The waler-equipped floats installed in Shilshole Bay Marina served for more than fifty years until the marina was refurbished to accommodate today’s larger boats. The marina was outfitted with new concrete docks, again built by Bellingham Marine. The final chapter attesting to the excellence and durability of Usab’s original design has not yet been written—many of Shilshole’s original floats were sold to private parties for residential and marina docks—and are still in service.
The genius of the waler system.
Usab’s patent describes the function of the walers as, “…to support the bolts or other fastening means, and to distribute the forces received therefrom throughout the structure.” This is the true genius of the waler system: distributed loads.
To understand the importance of distributed loads, consider alternate float connection systems in use today. Typical are systems which employ heavy-duty hinged steel bolts or large stranded cables at the corners of the floats. There are two problems with these systems. First, the connection hardware can, and does fail. It may weaken under repeated bending and attack from galvanic corrosion. Second, forces on the floats are not distributed, but are concentrated at the corners of the floats. Thus enormous shear loads are focused where they can result in irreparable damage to the concrete body of the float.
Quantifying the advantage of a distributed-load system.
Stress analysis of structures is a complicated science, but by reducing the analysis to its fundamentals we can compare the systems with clarity and understanding. The easy-to-follow example below will demonstrate the advantage of distributed-load systems over point-loaded systems.
A practical example: follow the stresses
A large powerboat is moored to a concrete floating dock in a storm. The boat’s considerable “sail area,” the currents in the marina, and the pulse of waves against the boat are all transmitted through its mooring lines into the floating concrete dock. These forces translate through the dock and are felt as shear forces at the module connections. In our example, the resultant shear force at the connection points between the floats is 10,000 pounds. In an actual marina in an actual storm, it could be more or less, but 10,000 lbs. gives us a round number to work with.
Figure A. Hinged Connection System
On the hinged or cable-connected system, the load is applied to the corners of the floats as a shear load of 5,000 lbs. applied equally to each of the four corners. The load is transferred through the hinge or cable to the concrete at the corners. The concrete structure must contend with a shear load of 5,000 lbs. at the vulnerable corners of the floats.
Figure B. Waler Connection System
By contrast, a Unifloat system with a typical complement of 10 through rods receives the same 10,000 pound load. Unlike the hinged system, where loads are concentrated at the corners, the shear load is translated up and down the waler and distributed among all the through-rod entry/exit points. Each of the 20 entry/exit points in the concrete structure must contend with 1,000 lbs. of shear force. The waler system, with its distributed-load design, has reduced the load on the concrete structure by 80%.
Other distributed load systems
Distributed-load engineered structures are everywhere around us. Donald Douglass and John Northrop transformed airframe design by using the skin of the airplane for load distribution in the DC-3. Cable-stayed bridges (see photo nearby) are easy-to-understand examples of distributed loads. In a more commonplace example, consider your house, constructed of dimensional lumber sandwiched between exterior plywood cladding and interior sheet rock. While houses are ubiquitous and taken for granted, they are actually marvels of distributed load technology as proven by their amazing strength in earthquakes.
The benefits of structural timber
As stated earlier, the vast majority of Unifloat marinas employ walers made of structural timbers. Marina owners intuitively ask, is a wood-waler marina as strong as it needs to be? It’s human nature to assume that floats connected by steel bolts or cables must be stronger. While it may seem counterintuitive, the choice of structural timber for walers is a deliberate decision taken for the purpose of building the strongest, most durable, most practical and most attractive marina on the market.
The selection of timber as the material of choice for walers is based on structural engineering considerations. Wood is the most widely-used construction material in the world. It’s the perfect material for corrosive environments that are in constant motion. Wood is a natural material. Its cell structure has adapted to bending motion. It maintains its strength under repeated bending motion when metal structures would degrade and fail under the same conditions. Wood can take more sudden impact without permanent deformation than equivalent metal structures. Wood is impervious to galvanic corrosion.
The test of a strong marina.
Most importantly, timber has proven itself in marinas around the world. The American coastline from the East Coast through Florida and around the Gulf of Mexico to Texas is a test laboratory for wood-waler marinas. They have been tested over the years in some of the most horrific storms recorded, and the wood-waler system has been more than up to the task. Hurricane Ike roared into Galveston Bay on September 13, 2008 and took aim at Unifloat-equipped Bayland Marina in Baytown, Texas. The “100-year storm” event was the third costliest hurricane ever to make landfall in the US. The Unifloat marina took the worst of the storm until a tide surge lifted the floats over the tops of the pilings. The floats then drifted toward a lee shore and were stopped by a line of trees. When the storm passed, marina officials found the marina largely intact on the beach across the bay…the floats still connected together by the wood walers!
Leonardo da Vinci said, “Simplicity is the ultimate sophistication.” He could have been describing the Unifloat waler-connection system. While it may look like a simple idea, Ernest Usab’s method for connecting the floats using a distributed-load concept is an elegant engineering solution that has proven its genius over time. While Bellingham Marine can, and has, built marinas with walers of other materials, the structural-timber waler is the standard by which all other float-connection systems are measured.
This innovative berthing solution for mid-sized bulk carries provided the client with a best value alternative to the original design concept.
Bellingham Marine’s company strategy is fairly simple; provide each client with a solution that provides the best value for their specific project and criteria. In order to find a balance between price and performance, each project must be looked at through its own unique lens. The company relies heavily upon the expertise of its employees, its experience in the industry, and its network of outside professionals to provide each client with a best value option.
Innovation is embraced as a means to achieve “best value” rather than a goal in and of itself. It is this focus on value and ability to provide innovative solutions that allows Bellingham Marine to excel in its niche market and to be comfortable and successful in taking on unique, one-off projects.
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Bellingham Marine now has an option for an FRP through-rod. The innovative product provides clients with a non-corrosive alternative to the traditional galvanized through-rod.
With a reputation for leading the marina industry in design excellence, Bellingham Marine looks toward the future with its eyes firmly fixed on innovation and user experience. The company’s unwavering commitment to customer service, engineering excellence, and its R&D program are key elements of Bellingham’s success in the marina industry and some of the key motivations behind buying a Bellingham Marine dock system.
“Our R&D efforts have long focused on improving user experience,” remarked Bellingham Marine President and CEO, Everett Babbitt. “Higher freeboards for greater user comfort; increased load capacities to support large crowds and vehicles on the docks; improved aesthetics and design details to set high-end facilities apart; and continued product refinement to promote greater longevity have been at the core of many of the company’s product advancements over the past ten years.”
“Now, new technologies and major breakthroughs in engineering are allowing us to elevate our product offerings and improve user experience on a whole new level,” added Babbitt.
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Paddleboarders cruise through the waters of Marina del Rey near Burton Chace Park in California.
If you spend much time at all around the water you’ve likely noticed an increase in the popularity of human powered watercraft – these include row boats, paddle boats, pedal boats, canoes, kayaks, surf skis, standup paddleboards, rowing shells or anything else that is propelled by human power.
Sales for standup paddleboards (SUP) have increased dramatically since 2007 when they were first introduced in the United States. Last year SUP sales were estimated at $15.6 million. Rowing clubs are springing up in cities everywhere that have access to an appropriate body of water and schools across the U.S. are experiencing a dramatic increase in participation in rowing programs. Kayak manufacturers are also reporting a steady rise in sales. Kayaking appeals to a board range of individuals including fishers and divers and is quickly becoming a mainstream recreational activity.
The growth in popularity of human powered watercraft is fueled by a number of things from cost, to ease of use and family participation, to rowing’s growing profile and to a greater emphasis being placed on the importance of physical exercise and being outdoors.
So what does this mean for the marina industry, which traditionally caters to sail and power boats 20’ and larger?
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Concern for the environment is not just good marketing—a healthy environment is essential for the future of boating.
More and more marinas are embracing a “green” approach to the design, construction and operation of their facilities. So, how do marinas that have taken this approach leverage their efforts to market their brand and increase their goodwill? We interviewed Jamie Welsh, CEO and founder of the environmental-services consulting firm 10% Solution to learn more.
As every operator knows, the marina industry is changing. Boat owners are becoming more conscious of the environment; they are beginning to see the earth’s resources are finite and the environment as fragile. Marina operators with an ecology story to tell can develop effective marketing programs that reach out to current and new generations of boaters.
Ecology marketing has power for three reasons. (1) An ecology story evokes universally positive associations. (2) Ecology is a simple, direct message that appeals on an emotional level. It commands attention and is easy to remember. (3) Marinas can leverage their ecology story to build connections to the community. While “cause marketing” has been misused at times, marina operators, as a group, should embrace it. We have much to be proud of. The industry’s record on the environment is excellent.
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Improvements made to the Unifloat concrete floating dock system have improved the system’s durability, longevity and performance.
Typically on our blog I like to write technical or educational pieces that have an overall focus on marina design best practice, innovation and industry trends. I make a conscious effort to stay away from brand specific pieces as I do not want to compromise the credibility of our blog by including sales pitches.
This article strays a bit from my traditional focus but I thought it still worthwhile to share as many of our readers are familiar with the Unifloat concrete dock system and may have the same question one of our recent clients had – What is the difference between the Unifloat system you produce today vs. the one you manufactured thirty to forty years ago?
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Milltown Marina is a great example of a modern, urban marina that was designed and built to provide the best value for the owner and the facility’s users.
Canada’s newest marina, Milltown Marina, sits on the outskirts of downtown Vancouver, B.C. in a well-protected basin on the North Arm of the Frasier River. The marina’s story is not that different from other Greenfield projects, and it’s actually the commonalities that it shares with other projects that makes it an interesting case study. Milltown started out the way many new marina projects do with a vision for the site, then a concept design and finally a layout for the docks followed by an issuance of a Request for Proposal (RFP).
Like a growing number of Greenfield marina projects, the response to the RFP is where the Milltown project deviated from its original course. The original plan was to get bids from dock builders to supply the docks that when assembled in the water by a general contractor would make up the configuration shown in the original drawing. The anchoring system would be supplied and installed by a third party and the utilities and accessory packages would be handled separately. This approach was designed to cut out any middlemen and avoid extra markups. In theory, the concept makes sense. The problem is that the modern marina is a complex web of interconnected systems that is most often best approached as a single system by a marina builder who specializes in the design/build of marina systems and who can take advantage of economies of scale. This is where the real savings happens.
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The LMU boathouse sits on a floating platform and features a low freeboard dock on the front of the building for launching shells.
The modern floating platform can serve a variety of functions for marinas as well as a number of other sectors. From gathering spaces to boat storage areas to foundations for floating buildings, advances in modern engineering have greatly expanded the possibilities for these unique structures.
In its simplest form, the modern floating platform is a custom-built structure, typically comprised of individual concrete modules joined together to form a broad surface or foundation that is, for all intents, a solid unit. These floating structures are extremely tough and can be designed to handle tremendous loads.
The simplest of the platform structures are those that serve as gathering and /or boat launch areas but even those can have a number of unique features and loading requirements. Examples include sloping freeboards, small boat or equipment storage areas, davit cranes, boat elevators, steps, railings and canopy systems.
On the other end of the spectrum are platforms designed to serve as floating foundations for large superstructures. When compared to those used to support people and boating activities, these platforms are extremely complex. Calculating the center of buoyancy and ensuring a final proper freeboard can be a challenge.
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Stamped concrete decks are an easy way to add an architectural detail to your marina facility.
As one year comes to a close and a new year begins, we are often asked “what is your outlook for the coming year for the marina industry” or “what are some of the trends you’re seeing and what can we expect to see more of.”
Although much of our comments are logged by editors and shared in their publications, I thought it worthwhile to share some of our comments directly with our readers…
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