Application of the Public Buildings for the Korean-style houses in the availability of R&D technologies : Focused on Drawings of Agricultural Education and Experience Center in Na-Ju, Korea

1.1. Purpose and meaning of the research

Various researches and architectural attempts on traditional architectural field prior on residential facility have been continued due to the rapid increasing of interest for Hanok. Especially, hanok type public building projects can be expected as cultural industry which can announce Korean architecture to the world with Korean wave as well as social ripple effect. Ministry of Land, Transport and Maritime Affairs has been selected ‘Hanok Building Support Project’ every year and support the budget as a plan to revitalize hanok type public building since June 2012, and to fulfill it, the revitalization plan of several government institutions are expanding all over the nation. Along with it, the research support and education for hanok preservation and culture support and promotion contents development also expanding the scale.

New-Hanok type public building model development and Implementation』project among hanok technology development research¹⁾ is succeed the brand value of traditional hanok and develop general hanok secures modern residential performance as well as public hanok building, and it is aimed to change the social understanding about hanok and create the foundation for hanok by popularization and generalization of hanok technology.

New-Hanok public buildings grafted advantages of hanok and rationality of modern technology have been built at Eunpyeong-gu, Seoul, Soonjang-gun, and site in Naju Agricultural Technology Learning Center, Jeollanam-do by New-Hanok Type Public Buildings Model Development and Implementation Project, and Naju Agricultural Technology Learning Center among them has been built as a education and research facility related to the agriculture for the lectures related to domestic agricultural technology and international agricultural exhibition. Naju Agricultural Technology Learning Center is one of the case applied new-hanok type public building concept of hanok technology development 2^nd phase demonstration implementation project. It applied the outcome of hanok technology development 1^st phase and also greatly significant as new style new-hanok type public building grafts modern architecture technology not usually used in existing hanok such as RC or glass curtain wall system.

In this thesis, the future value and improvement direction of new-hanok type public building applied on public building over the hanok shall be proposed through the check about the features of new-hanok technology applied on the design and construction of new-hanok public building and the planned features of total buildings reflected them based on the design documents of Naju Agricultural Technology Learning Center. Specially, the design change was mainly applied for effective construction of new-hanok type technology application, so to organize and analyze hanok applied technology appeared or disappeared during design change is positively necessary work for future expansion of new-hanok type public buildings and continuous competitiveness securing, and improving workability.

1.2. Method and Range of the Research

In this research, the research result of hanok technology development 1^st phase and hanok technology were reviewed preferentially to check the type and features of hanok technology applied on Naju Agricultural Technology Learning Center, and organize and analyze the application or not and applied degree of existing hanok technology as well as newly applied technology based on the trace for changed items on basic design drawings and detailed design drawings modified 9 times to reflect design plan discussion or construction suggestion, etc.

The basic and detailed design drawings of Hanin Architects & Associates elected for design of this project was reviewed for the analysis of hanok technology reflected on Naju Agricultural Technology Learning Center, and the technology suggestion of construction company and design discussion of research group also has been referred.

Object of the research is limited as Naju Agricultural Technology Learning Center. Besides, the definition or concept related to new-hanok in this thesis is following the standard of Hanok Technology Research Group.

2.1. Range of Education and Research Facility among New-Hanok Type Public Facilities

The definition of ‘New-Hanok’²⁾ under current law is not established institutionally, but it means the improvement to adapt modern life and environment by adopt advanced wooden architecture technology and system along with traditional value in academic significance.³⁾ Furthermore, new-hanok type public building is the building close to everyday life of the residents, and it includes the facilities to improve welfare, cultural benefit, and exchange of the residents.

Meanwhile, domestic education and research facility based on Building Act and Enforcement Ordinance includes every kinds of school, education center, vocational training center, private training center, laboratory, and library. These facilities are composed with education basic facility and research facility as well as support facility and affiliated facility. Among them, education center and laboratory are the space for main activity with unique independence and overall interconnection is most important. Especially, planned design on education and research facility as a public building is necessary to fulfill publicness and professionalism at the same time.

Fig. 1.

Distribution of Han-ok Public center

It is 128 sites⁴⁾ of hanok public buildings owned by central government and local government all over the country based on the statistics in 2015, and most of them are concentrated in culture and assembly facility in use (36.3%) (fig.1)⁵⁾.

As shown in fig. 1, the share of education and research facility⁶⁾ among hanok multi purposed facility is very low and more than half of them are located in Jeollanam-do, therefore, the regional deviation is severe and the construction was concentrated during 2008 ~ 2012. Most of them designed as wooden structure, but there are more than a little applied modern architecture technology such as reinforced concrete structure, etc. Also, the share of education center and laboratory including library and experience center is high in the check based on detailed facility type of education and research facility.

2.2. Construction Background and Design Outline of Naju Agricultural Technology Learning Center⁷⁾

The popularity of graft between education and research facility and new-hanok type public building shall be decreased than other use facilities because it has special features that the purpose of construction is clear and specific user range is limited.

Table 1.

Architecture and Structural Design Abstract

However, the graft of hanok with technology education facility planned based on Korean agriculture can be identity establishing of the facility and promotional alternative, and especially, in the case of Naju Agricultural Technology Learning Center, it is the space to host and progress agricultural exhibition, so the utilization plan before and after the exhibition should be considered separately.

Regarding Naju Agricultural Technology Learning Center, the detailed design was completed reflects the technology suggestion of construction company and research group on the basic design of elected plan decided by the discussion of professional organization and research group after select inviting organization through public contest of every local government for new-hanok type public building regional substantiation construction project on Dec. 2014. There had been 9 times of design change from elected plan to final detailed design based on the discussion among research group, engineering company, and construction company.

Naju Agricultural Technology Learning Center is a new-hanok type education and research facility located in Jeonnam Agricultural Research & Extension Services sites which is a building with two stories above ground combined RC structure and wooden structure. Building area is 374.94㎡ and detailed outline is as shown in below table 1. There are a Naju Plain village at northeast and formed continuous reservoirs and hydrologic system, and near waterside park and agricultural theme park.

3.1. Design Change Aspect and R&D Technology Application Range

The design plan have changed 9 times from first public contest prize elected plan. The characteristic change on plane plan for 3 times before and after detailed design from the alternation, and it is distinguished as previous plan and after plan by the detailed design reflects technology proposal of construction company after construction. Among them, design change stages are identified as 4^th, 6^th, and 9^th alternation and main contents and plane type are shown as in below Table 4.

A. The Substance of Naju Agricultural Technology Learning Center Design Change

The initial elected plan was designed traditional wooden technology and design method strengthen the symbolization, but modern construction way and the economic feasibility and efficiency expanding the range applying modern material were shown after detailed design.

The building-to-land ratio decreased 1.54% and floor area ratio decreased 0.68% than initial design plan and the mass also supplemented from parallel type to slenderly straight type. The alternatives which delete unnecessary design method and display space, secure convenient space, and fulfill economic requirements were applied.

Table 2.

Details design change in plan

Overall layout change including column lows and reducing mass was achieved until 2~3^th alternation, service space (toilet and storage) expansion plan to secure convenient space in 4^th alternation looks remarkable. Since then, the storehouse plan using upper part of 1st floor was suggested passing by 6^th alternation, and it is considering the traditional proportion and also considering construction workability and economic feasibility at the same time by omitting front column among 1 front column and 5 beams structure of initial design and changed as large arch type and could secure upper space and unified the mass arranged in a row for right and left.

Upper space of 1st floor is connected with 2nd floor and it is used as storehouse. Also, the preparation of frontality and openness assessment reflected after three times of discussion was completed based on higher accessability by omission of partial front columns and common hall type of front opens to front yard by independent positioning of stair hall at the rear from 6th alternation.

The change of the entrance of the toilet for disabled person is also for the amendment for publicness and convenience. Finally, the readjustment of toilet space, independent positioning of stairs, and improvement of public space shows the direction of the detailed design after selection of construction company.

Totally, maximized the traditional beauty of Korean style wooden structure and attempted the convergence with modern architectural structure adopted economic structure system, and at the same time, space composition of front corridor, exhibition hall at 2^nd floor, and terrace which are symbolic element of elevation design also placed emphasis on variable using of multi function space. However, concentrated the public function for the education room for lectures and hall including toilet considering service space and convenience to approach.

B. Range of New-hanok Technology Application Applied on Naju Agricultural Technology Learning Center

5 in 11 of 1^st Mandatory R&D technology firstly designated items reflected on the design of Naju Agricultural Technology Learning Center were constructed, but alternative technology 77 items had been amended or excluded after apply elected plan and detailed design. The reflection rate of alternative technology is 25% (19 items) and used at roof construction mostly from 6 construction process, and most of excluded technologies⁸⁾ (53%, 42 items) were mostly excluded because there was no work in this construction or the design condition was different.

Fig. 2.

NaJu Agricultural Education and Experience Center

Table 3.

list of R&D techniques & range of application

Also, 24 items of technology partially amended the method and applied or postponed to decide to reflect according to the site condition. It is worthy of notice on 9 technology groups applied after supplementation reflecting suggestion of construction company and research group. These improvement plans are the alternatives securing the reinforcement in performance for the defects can be appeared due to the difference of the construction condition (Table 2).

3.2. Focus on Hanok Cultural Assembly Facility Design

When simply imitation traditional design elements in new-hanok type public building, there can be a confusion when mixing other kind of materials or graft with modern architectural technologies. Also, the convenience and publicness of users should be considered when design education and experience center which are public facility though traditional architectural style is base for it.

A. Transmission Process of Traditional Beauty of Naju Traditional Government Office

The design concept of Naju Traditional Government Office is applied on Naju Agricultural Technology Learning Center. Especially, it was reconstituted the central place of Naju⁹⁾ Traditional government Office and hotel, "Geumseonggwan", so, it displaced 'space' concept, bilateral symmetry structure, realization of corridor and servant's rooms in traditional architecture for the symbolization as 'main government office' and fanciness.

Geumseonggwan has five rooms by 4 rooms and East-ikheon and west-ikheon¹⁰⁾ were restored during restore project and became current appearance.

Fig. 3.

Na-Ju’s Traditional Government Office (羅州牧 官衙)

Fig. 4.

NaJu Agricultural Education and Experience Center

To approach main office, passing through the main gate, 'Outer three gates' constructed as 3 rooms and 2^nd floor gate tower, then passing through 'Center three gates', and also 'Inner three gates' which is only remains as sites, then can arrive front yard of Geumseonggwan.

Table 4.

Symbolism of design approaches

These series of traditional processes had been simplified and reproduced through the 'Outer three gates' at the entrance part of existing construction site and 'Tall three gates' at the front of Agricultural Experience and Education Center'

B. Space Utilization Plan in Corridor as Multipurpose Use

Corridor is a passage installed to divide courtyard with main office as the center or surrounding the inner sanctum. In modern architecture, it is used as service space for events or indoor space meets outside air. Above all, the spatial atmosphere of corridor plays a buffer role for the traditional architecture transition to modern facility.

In Naju Agricultural Technology Learning Center, front of 1^st floor composed as corridor, so it strengthen the frontality and reminds open corridor of the main floored room of East-ikheon and west-ikheon, and rises the traditional beauty. Corridor completes three dimensional elevation looks like sticking out of the column of inner wall, and protect direct exposure of the opening connected to inside to outside air and possible to be used as front room.

Fig. 5.

Details design on corridor

Therefore, it was planned as a reception space for large scale events and lectures by a practical space connected with outside cultural facilities.

C. Storehouse Composition using Roof Upper Space

Use of attic frequently appeared in two storied hanok space have been mentioned several times in already constructed hanok-type public buildings. The attic in hanok library in Guro-gu established in 2009 used as children's space allotting it as sitting reading room, and used as assistant space for education in Geumgua Public Nursery School at Soonchang opened in 2016.

Table 5.

Details design in 1st floor on the attic

The plan using roof upper space as room basically a plan to increase the space utilization, but main structure should be come out as it is, so structural effect elements cannot be eliminated including plastering.

The construction method expanding roof space to omit crossbeam for right and left wings and installed hongye truss (arch truss) was applied on the roof space of Naju Agricultural Technology Learning Center.

The securing of storehouse was much needed because of the characteristic feature to perform the events related with agriculture. Insufficient warehouse facility by existing design could be solved by more enough attic space by hongye truss (arch truss) construction as storage and service space assists 2^nd floor exhibition hall.

D. Harmony between tradition wooden furniture structure and modern curtain wall

The stair hall installed at the rear of Naju Agricultural Technology Learning Center was constructed with modern structure using steel and glass not with traditional materials. It is interpreted as the plan to secure the safety for the lift for at weak pedestrians and to increase openness and conformability. Also, THK22 the curtain wall at stair hall two storied glass, so it solved visual closure due to the stair hall height.

Fig. 6.

Rear design

The glass which is modern architectural material is used for stair hall, but it is planned to minimize decoration elements and reducing the sense of difference, and the facility to assist indoor lighting and aims the convenience of the user was applied. It is the convergent of traditional hanok with modern material and construction method, and can be said as an attempt to suggest the development direction and possibility of new-hanok type public building in the future.

E. Reflection of Design Standard for Disabled Person Convenient Facility

Based on social requirement increasing the awareness and expectation for weak pedestrian including disabled person and seniors through advanced research, more detailed and reasonable standard is necessary on the barrier free certification system applied on new-hanok type public buildings.

Table 6.

Naju planning regulations pursuant to the Building Act

Table 7.

Disabled facilities installation plan lists and coverage

Jeollanam-do obliged BF certification for overall public buildings and it affected on plane design after detailed design as an important factor.¹¹⁾

The laws related to public building applied on Naju Agricultural Technology Learning Center are as shown in Table 8. Based on the BF design instructions applied by architectural area base according to the Naju-si planning ordinance, considered wheelchair moving line by the reducing the step difference between buildings and installed access ramp at the front of entrance, and expanded stair hall size which was poor due to the toilet arranged as parallel with classroom, and also adopted modern facilities to contribute in safety of elevator operation in Naju Agricultural Technology Learning Center.

Besides, it considered visually handicapped for vertical movement as well as horizontal movement in the space by installing braille signs and punctiform block in overall indoor space.

Table 8.

Details of Disabled Accessible Design

3.3. Moving Line Establishment focused on Publicness and Assembly

Outer space of government office was planned with gradual space movement and ideal symbolic trees, and the access road of Naju government also shows typical composition passing through outer three gates, middle gate and arrive main office. However, it is concentrated to build service area to prepare as a public facility and intermediate space embracing event yard according to the design direction based on the publicness and rationality than symbolization and traditionality through the modern reinterpretation process of Geumseonggwan in Naju government office for Naju Agricultural Technology Learning Center.

Representatively, it reduced the inconvenience in passing through by reducing the column quantities of corridor space which had symbolic design effect in initial design and arranged the service space such as toilet and supply room at front to increase the connectivity with outdoor event yard. Also, allocated the offices which were distributed closely with the classrooms, so improved the moving line of work and lecture related to be concentrated. Different with open type 1^st floor, divided the territory of 2^nd floor to be used as a complete exhibition space and rooftop terrace to be used as outside exhibition and rest area.

In general, the rooms have been arranged separating the floor according to the purpose and characteristics of space use, but planned design goal is revealed to secure publicness by the effort to reflect the design plan considering safe movement of weak pedestrian including disabled person and the elderly and the infirm and shorten the moving line.

4.1. Range of New-hanok Technology and Construction Suggestion Technology

New-hanok technology reflected at construction phase were applied through the discussion with research group and construction company based on reasonable construction cost and structure system advantageous for construction duration shortening.

The range of applied technology can be divided as construction for each part and maintenance program after completion of construction, and the reflected technologies totally increased after detailed design as shown in Table 5. But, reflected technologies were beyond half of the list research group suggested during design change process, it was largely because of unreasonable process and construction cost increasing, and also it was excluded because the technology was researched for residential architecture, so it was different condition with public buildings.

Table 9.

list of required R&D techniques

Iron reinforcement R&D application plan in wall construction technology was discussed to reflect it whether it is really necessary or not, but excluded because it was judged as unnecessary during construction, but flooring work which was excluded because it was different with design condition was managed to reflect partial construction method. Nevertheless, many of the technologies could not applied because they were not correspond with site condition and design condition.

Main new-hanok technologies in Naju Agricultural Technology Learning Center are Corner Column Type and Central Column Type Member of Framework Joint (Technology no. 10-1263628~1263630), Complementary Rafter (Technology no. 10-1374163), and Tubular Column Connector (Application no. 10-2014-0087245).

Among them, Korean style system window composition for openness, use of complementary rafter and light roof tile for lightening, danggolmakyee for insulation and improving air tightness are representative application case of R&D technology improving durability and considering traditional beauty.

Especially, it is necessary to pay attention that the roof upper space was secured on each iksa applying hongye truss (arch truss) which was suggest technology for construction on Naju Agricultural Technology Learning Center. The upper part structure planned as large scaled arch in initial design plan changed and constructed as hongye truss (arch truss)(Table 6).

Table 10.

Details design change in the attic

Table 11.

Details design on Hong-Ye truss

There are construction process that cut a groove on the purlin and whole setting and put up the ridge beam, then reinforce with metal joint. The roof of hongye truss section used dimension lumber rafters instead of circumference rafters, and OSB plywood for structural use instead of Ceiling Board to finish with exposure.

Hongye truss became direct element to solve the structural problem to secure upper space of roof , and has a meaning as first case constructed with suggested technology method of construction company for new-hanok public building.

4.2. Economic Feasibility and Construct Ability of New-hanok Technology

Based on the research for Korean style public buildings built for last 10 years¹²⁾ new-hanok type has highest rate of 41 in 60 cases.¹³⁾

Table 12.

Neo-Korean Style Public Architecture Status of the composition

In comparing with expense unit price between architectural area of new-hanok public building and total construction area in the contents of Table 5¹⁴⁾, regular correlation can be identified on design unit price between structure type and architectural area.

In case of architectural area, it is surveyed as large in principal for traditional type and wooden furniture structure combined with RC structure, and in case of cost, below 10 million won in unit price per pyeong are far higher in the structure combined with RC structure.

Naju Agricultural Technology Learning Center used combined traditional method and reinforced concrete method and medium range of traditional and modern method mixture group, but the construction cost is lowest in comparison.

Of course, to discuss about the economic feasibility with total construction cost and area without the comparison between the process is not a good comparison element. However, in considering that new-hanok technology is not generalized at this moment, so it can be identified that the construction cost in contrast with area in new-hanok technology secures the economic feasibility.

4.3. Reflecting Construction Company Suggested Technology and Combination with Modern Construction Materials

New-hanok technology divided as 88 detailed items separated as essential skill and optional skills under 12 processes. 22 R&D items were applied and 42 items were eliminated in Naju Agricultural Technology Learning Center.

24 items were partially applied or substituted with improvement suggestion and it can be announced that it got a fruitful outcome in the way that it suggested construction alternative to overcome the limitation of existing technology.

Table 13.

list of R&D techniques & range of application

Construction suggestion technology were reflected on 9 detailed items in wall, floor, roof, and ceiling process.

Representatively, the process used danggolmakyee in roof was arranged as amendment with partial modification and construction to supplement difficulty in use of standard part in site construction, especially in end pieces.

In wall construction, insulator construction to maintain insulation performance of wooden structure and used tight tape for joint on the gap created on frame when construct structure and improved by putting trimming timber to improve the durability.

New-hanok technology have been researched to improve existing construction method depend on the experts, and also improve overall materials performance, and the ultimate aim of them are widespread and generalization of hanok by reducing supply unit price and building the distribution structure as a result. However, to overcome the limit of technology group developed and researched based on residential architecture, the construct ability and economic feasibility in various aspects will be very important requirement. In this point of view, the reflection of construction suggestion technology in Naju Agricultural Technology Learning Center can be evaluated as the attempt to prove the improvement direction and development possibility of existing hanok technology.

Meanwhile, securing publicness giving priority as public building should reflect convenience and universality. In this aspect, the plan to increase the satisfaction of modern users will be positive plan to resolve existing inconvenience with most modern and technical equipments than the space stick to the traditional method, and it can be more realistic solution.

Naju Agricultural Technology Learning Center also reflects these social aspect and the stair hall finished with glass curtain wall was came from the safety and practicality not by simple considering of design function.

4.4. Design Plan applied Traditional Architectural Elements

New concept of publicness need to consider¹⁵⁾ history and culture of the region, urban context, or macroscopic frame premising nature, tradition, and long historical frame.

The hanok element of Naju Agricultural Technology Learning Center shows intentional design plan to highlight decorative beauty as well as following traditional method.

Representatively, designed the window type according to the function, latticed rib door for gate, transom window (comb) for dome window (high window), and band rib window for other windows, and constituted the eaves with all exposing rafters for everywhere not constructed boarded ceiling.

Improved Korean style roof tile increased construction performance through new construction method was used. Also, fire control wall and traditional pattern were used for modern reinterpretation for the harmony with Korean style outer wall in the finishing of outer wall treatment of RC structure.

Fig. 7.

Picture of Traditional design elements