The objective of this paper is to explore the differentiation of the system in traditional Korean wooden architecture specifically focusing on the overall structure. The reason for planning this study was the question of why the order of construction ...
The objective of this paper is to explore the differentiation of the system in traditional Korean wooden architecture specifically focusing on the overall structure. The reason for planning this study was the question of why the order of construction is always explained in the order of stylobate, foundation stone, plane, column, beam, king post, girder, and rafter when studying traditional wooden architecture. You might think “you can’t build a beam without a column.” but the reason for setting up a column is to lift the beam and girder. If there is no rafter, there is no need for a girder, and if there is no girder, there is no need for a beam and column. The order of construction and the order of structural inevitability are not the same. Although the detailed type classification of partial structures or decorations is also important, I was curious about the system that is divided and branched out logically from the most essential member and structure of framework from the perspective of the overall structure.
To establish the system, I traced the beginning of architecture. In the case of Korea, it is estimated to be in the Neolithic period, and the structural member that supports the thatch that block the rain by weaving linear members of wood, that is, the rafter, is the starting point of the architectural structure system. The occurrence of the ridge girder, which was made by making a one-dimensional line from a dimensionless point at the top of the rafters, revolutionized the architectural space. The column that lifted the rafters separated the roof structure from the wall structure. This is the differentiation of the structural system of the formation period of traditional Korean wooden architecture from the perspective of the overall structure.
Afterwards, Korea, along with China and Japan, shared the genetic factors of East Asian wooden architecture and developed the formal framework of architecture. Shared genetic factors include wooden structure, tiled roofs, deep eaves, high stylobate, and the development of Gongpo(栱包). Korea, China, and Japan have deeply influenced each other and have reached a technical peak. This is the establishment period of traditional Korean wooden architecture. However, it is not easy to trace the system because there are not many buildings left in Korea during this period.
Afterwards, Korea, China, and Japan evolved the structural system according to their respective circumstances while incorporating shared genetic factors of accumulated technical skills. This is the establishment period of traditional Korean wooden architecture. Many buildings from this period still remain in Korea, and I would like to trace the structural system through them. This will include the structural system of the establishment period.
From the original Rafter Structure, the structural system of the roof structure and wall structure that evolved separately was established.
The structural branching point in the roof structure is the topmost member of the roof. The structural system was differentiated into the Ridge Girder Structure, which made the top of the roof a one-dimensional line, and the Oksimju(a column that support the rafters at the center of plane, 屋心柱) Structure, which maintained the tradition of a dimensionless point. The Ridge Girder Structure has a grid-shaped plane, and the Oksimju Structure has a radial plane. Each has a different structural system for composing members due to the characteristics of load flow.
The arrangement of the rafters determines the shape of the roof, and the framework for constructing the shape of the roof becomes the structural branching point of the structural system. The arrangement of the rafters can be classified into three types: unfolded, joined, and overlapped. The unfolded rafters are the most fundamental arrangement that forms the roof plane, and each rafters is made in a Closed State or Open State. To make the width of the Major Two-dimentional Load-bearing Areas even wider, the rafters are joined, and the joint of the rafters requires a middle-purlin. The overlapping of the rafters makes the roof structure more abundant in various parts.
In the Ridge Girder Structure, the Open Eaves make an Open Roof called “matbaejibung” in Korean. If an Open State is formed above the Closed Eaves, it is called “paljakjibung” in Korean. If a Closed State is formed above the Closed Eaves, it is called “ujingakjibung” in Korean. The Oksimju Structure must have a Closed Eaves and a Closed Roof, and is called “moimjibung” in Korean.
The Ridge Girder Structure branched out into the Open Eaves and Closed Eaves to form a structural system. The Open Eaves have a relatively simple structural system, but the Closed Eaves form independent structural systems from the perspective of the side room framework and the roof-shaped framework, respectively, and are combined to form one structure.
The Oksimju Structure can only have a Closed Eaves and a Closed Roof, so the arrangement of the rafters cannot be a structural branching point, and the Busangju(an Oksimju that is over the ground, 浮上柱) Structure and Simju(an Oksimju that is on the ground, 心柱) Structure form a structural system depending on the state of the Oksimju. However, the structural system of the Oksimju Structure is entangled because the beams, middle-purlin frameworks, rafters, and floor state of the Oksimju do not have a strong dependency.
The wall structure evolved from a single-story structure that erected columns of appropriate height at the intersection of the beam and the girder to a multistory structure that overlapped storys by raising the wall.
The structural branching point in the multistory structure is the degree of the structural cohesion between storys. The structural system of the multistory structure is differentiated into a Respective Storys Structure that combines the stacked storys structure in which each story has an independent structural system and an Integrated Story Structure that adds structures that distinguishes story in the structure that surrounds the entire story.
There are structures morphologically with and without a horizontal reduction between the lower story and the upper story in the multistory structure. The structure without a horizontal reduction is a building with one roof externally and uses a “numaru(樓)” which overlapping the floor inside. The structure with a horizontal reduction forms a roof between storys externally, but internally, it can be used as a single floor without overlapping the floor or multi floor with overlapping the floor.
The Respective Storys Structure with a horizontal reduction stacks the floors that are structurally reduced. And the weak structural cohesion between upper and lower storys allows for subtle reduction. However, the Integrated Story Structure with a horizontal reduction does not have a structure that is structurally reduced, but the lower part of the integral structure forms a surrounding space and expands horizontally. For this reason, the Integrated Story Structure is reduced in units of one or half a unit(a distance between inner column and outer column, 間).
A case analysis on the structural system of 233 major buildings of traditional Korean wooden architecture was conducted to interpret the trends.
The structural system of architecture is dynamis. Energeia arises from the dynamis, but the dynamis cannot completely confine energeia within its boundaries. This is because there are mutations in energeia. Therefore, it is necessary to establish a structural system to avoid losing coordinates by jumping into the sea of energeia without holding a map of the dynamis.
Keywords: matbaejibung, paljakjibung, ujingakjibung, moimjibung, multistory