01. General concept
The desire to create an iconic building resulted in the main idea behind proposed design for Thematic Pavilion. Our inspiration came from 317 islands that Yeosu peninsula consists of and beautiful natural environment of the coastal triangle. Instead of designing another building we decided to create a landmark that will be harmonious with the existing landscape – a picturesque artificial island.
We strongly believe, that for almost everyone, no matter the cultural and educational background, an outline of a beautiful island brings the thoughts of pleasure and happiness. Discovering an island is for many people the moment of the most intimate contact they can make with the ocean and its coast. Islands have always exerted immense fascination upon the inhabitants of our globe. Spending some time on an island, away from the hectic life of our civilisation, taking pictures of this precious moment is a key point of many travels all over the world.
The industrialization of the existing EXPO site and disappearing of natural coasts have brought severe damage to the health of the ocean. By designing Thematic Pavilion on the open waters we felt obliged to think about restoring natural coastal landscape. The island theme seems to be an ideal answer to a difficult question of creating unique architectural icon and at the same time respecting environment and its issues.
02. Architectural design
In order to achieve an ideal island outline, but also to keep the cost of the construction at the reasonable level, we decided to design it as a spatial structure. We have used an ideal module that is not quite regular but can fill the space completely. In this way we created the whole structure using only one type of geometric element, and only differing slightly the filling elements in it. The scale and form of the module was also inspired by prefabricated elements that the breakwaters at Expo site are built from. This form is used worldwide and is strongly recognizable.
As a result, the whole island looks light and eternal, resembling a reef structure or pumice rock. The interior effect will be overwhelming, with the light penetrating the three-dimensional dome and the movement of shadows on all surfaces. The Thematic Pavilion should encourage all kinds of interrelations with the environment. We hope for the structure to become a home for different species of birds, and we plan to grow algae on its elements. This building should be functioning as a real island would, and it has to be able to change in time and space flexibly. Accordingly, the difficult conditions of its location in the ocean open waters will only enhance the architecture, adding life and patine to it. The slopes of the island will start to differ, the southern one getting more sun and allowing the greenery to spread.
All modules will be covered with shotcrete, concrete sprayed with high pressure pumps reinforced with fibers. Thus acquired surface will have the character of natural rocks and hopefully will encourage all life forms to set in. But true nature of the pavilion will show after the dusk. When enlighten from the inside, the island will suddenly come to life, showing transparency of the structure. The effect will be doubled thanks to reflection in steady waters of Yeosu bay.
03. Functional arrangements
The function in the building follows the logic of an island. It does not have any physical connection with breakwaters, and can be reached only by water. Water trams dedicated for this purpose circulate around the pavilion, making two stops at designed location. At first one, on the southern end of the island, visitors will descend onto a platform. This would be the main floor of activities, located during high tide just above the water level. Here it would be possible to make physical contact with the ocean and truly appreciate its unique climate. The outer space would be open to elements, only partially shadowed by the structure. The restaurant close to the descent to water will offer delicacies made from algae growing on the island, there will be sounds from birds and air full of oxygen and moisture.
From this level, where visitors will be experiencing the ocean with all their senses in a very emotional way, they will have access to exhibition spaces located underneath. They will be tempted by two grand openings with amphitheaters made off stairs and glass water tanks filled with structure and algae. These tanks will be in fact the lungs of the whole island, using energy from tides to pump water in all cells of structure, enabling algae to grow.
The exhibition space is divided into two parts: the Best Practices Area and Theme Exhibition Area. They can be visited separately if needed, or jointly creating a certain route. Because of their underwater location, the only daylight that is allowed comes optically distorted through the water tanks or perforation in external walls. The underwater space is designed to be flexible and allows to incorporate all kinds of exhibition plan.
After visiting the exhibitions, one can descend from the main platform to the 'sea walk', an underwater pedestrian connection with Big 'O', or leave by water tram using second stop at northern end of island.
04. Sustainable solutions
It was crucial during the design process to concentrate on solutions for the pavilion that will not only be eco-friendly, but will also have educational and architectural meaning. The main structure will be made of steel because of based in neighborhood Gwangyang Bay Area Free Economic Zone, that focuses on steel production, so the cost of transport will be relatively low.
Tidal power was chosen as renewable energy source for the pavilion. It would be effective because of tidal height in this location, and also the most representative for the ocean pavilion. To make visitors aware of the whole process taking place in the building, we decided to place strategically two water tanks that will show water movement dependent on tides. Due to this movement also the area and outline of the island will be changing constantly.
Another important issue is an after-life of the pavilion. We believe that that thanks to its original concept and constant change in time it will be attracting visitors long after Expo exhibition. But we can foresee the possibility of reducing program and floor area. The modularity of structure will enable further edition of the project.
Expo Thematic Pavilion in South Korea will be created as part of a regeneration programme of Yeosu harbour. The intention of the design team is that the pavilion is perceived as an island sitting in the harbour marine environment. Although the man-made object, the pavilion should be perceived as an object in harmony with the surroundings.
In optimising the design all three aspects of sustainability were taken into account – impact on environment, cost implications and social benefits were balanced to provide the best solution. The social criteria included provision of an attractive exposition pavilion that would encourage people to travel and be recognized as a place to visit. Environmental design focused on selection of construction materials, impact of construction methods on marine environment, maximizing use of renewable energy and locally available resources. Costs were considered in selecting the most appropriate and effective construction method and selecting a repetitive form of a star module. Also energy efficiency of the systems will be maximized and renewables used to reduce running costs.
Visually the pavilion will be corresponding with natural appearance of the rock islands typical for the region. Irregular and random surface created by star modular elements will refer to a natural structure of coral reef.
Structure and surface finish of the star elements will enable marine organisms to attach to the modules and survive in ‘water pockets’ created within the star shape. The pockets below the high tide line will be naturally filled with sea water during the tides. The higher elements may require additional water supply through the pipework. In time, the building skin will merge the building with the surroundings and give it even more natural look.
The structural solutions, described in other section of the document, were carefully and consciously selected to cause minimal interventions into the sea bed and protect natural environment. At the same time piling method provides opportunity for the structure to be truly surrounded by waters and integrate with the environment. It is envisaged that concrete structure will provide best durability and will perform in underwater environment well, providing at the same time benefits of high thermal mass and possibility to integrate heating/cooling ducts or pipework.
The building systems will be designed to maximize use of available resources:
The amplitude of tidal levels encourages introduction of power generating units. Although the efficiency of the system will be limited by the area available for a storage tank, it is believed that it would be appropriate to demonstrate how tidal energy could be used. It is considered that the tidal water will enter the building from underneath. The water will enter the pool through the opening created in the bottom slab. Transparent walls of the pool will allow spectators to observe how water evacuating from the pool is powering the turbine generating electricity.
At the moment it was assumed that waves entering the harbour will not be sufficient for a ‘snake’ type of power generator. However further studies will investigate how the installation in the open sea could support a system providing energy to the expo pavilions.
Steady temperature of the surrounding sea waters will be used to control internal environment affected by changing external conditions. To multiply efficiency of the temperature differences between the air and water temperature the heat pumps will be used to cool or heat the building. Lower source heat exchanger will be installed below the water level, at the depth providing optimal parameters. Thermal mass of the construction materials will be used to support mechanical systems in maintaining steady comfort parameters inside the building.
Throughout the building the high efficiency equipment will be used to reuse energy from evacuated air (heat exchangers).
Natural light will be delivered to the building through tubular skylights. If the overall natural appearance of the island will not be affected by installation of the external devices harvesting natural energy, the team will consider use of photovoltaic units or vertical, silent wind turbines, solar panels for hot water, etc. The devices would be installed to the star modules in discrete location at the best exposure to the natural source of energy (sun radiance, prevailing wind directions).
05. Structure and foundations design
Due to the fact that the building main level is in a substantial part under the water level, there are two major construction issues related to the building, which cannot be separated: foundations of the building and method of construction.
Foundations design has to take into consideration that the water level varies and with the high water levels the weight of the building will not balance the uplift force resulting from the hydrostatic pressure. The solution should minimise the impact on the underwater environment and represent also an economical approach. Same rules should be applied also to the proposed construction method.
Due to the above it has been decided that the building will be founded on piles, which will be supported on the soft rock layer and will provide stability against the changing water levels. The foundation slab of the building will not be laying on the bottom of the sea, but will be fully supported on the piles. This solution allows for a free water movement under the building minimizing adverse impact on the sea life. The foundation slab will be formed as box sections, which would enable introducing additional weight to the structure (by filling the empty space with concrete), in case the uplift capacity of the piles occurred not enough.