2024/09/17

Taiwan Today

Taiwan Review

The complex engineering of China's architectural treasures

July 01, 1983
Traditional Chinese architecture-a graceful curved roof, multiple columns, and bright colors-is appropriately demonstrated in metropolitan Kaohsiung's Confucian Temple
Among evidences of the Yin period (the latter part of the Shang Dynasty) found in what is today Anyang County, Honan Province, in mainland China, are remains of the Shang capital. The Dynas­ty reigned from 1766-1123 B.C.: from its remains, we have learned that tou, (round underground caves) and chiao (square underground vaults) were already in existence over that period. En­graved artifacts found in the area included black ware, stoneware, bronzeware, and oracle bones. Earthen walls (with holes, seemingly to support wooden roof beams) were constructed around a cave entrance. From outside the cave, earthen steps led into its interior. Here we have, exactly, the primitive "thatched house with earthen steps" —the most ancient Chinese dwelling described in historical records.

At the Hsiaotun Yin ruins (Hsiaotun Village, five li nothwest of Anyang County) loess platform bases were surmounted by stone plinths, to each of which were attached bronze footings. We can infer their use in wooden buildings, thus establishing the existence of such structures in the Shang.

For several thousand years, tradi­tional Chinese public buildings, both large and small scale, adhered to certain rules. Generally speaking, each such complex was surrounded by walls, and the main hall of a complex took the north-south attitude, being sited at the north end and facing south. Secondary buildings were arranged facing either to the east or the west.

The Han people in the Yellow River Valley used hard rammed earth to build walls and as platforms for buildings; the earth also provided raw material for bricks and tiles. The verdant forests provided plentiful materials for columns, beams, doors, and windows. By the Chin (221-207 B.C,) or, perhaps, the Han (206 B.C.-220 A.D,) Dynasty, completely wooden construction was the rule, setting patterns followed for the next several thousand years of Chinese history.

The so-called "curtain walls" of such structures sustain no weight, except for their own materials. Usually, the south wall of the main building offers its only windows and doors. A broad sweeping roof shows from front and sides the grace and power of flying eaves. This design serves to intercept the scorching rays of the summer sun, whereas the south wall is kept warm in winter due to the low slanting sun of that season.

The weight of the majestic roof is sustained by columns. Between the roof and the capitals is a group of finely constructed, weight-bearing components - tou and kung. To bind these construc­tion parts, precision tenons are utilized instead of iron nails.

The columns themselves are planted on chih (a layer of something to pre­ vent the water coming up from the ground to erode the column, used only for certain ranks of buildings) and boul­der stone bases mounted on huge stone slabs. The columns are not cemented down, the weight of the stones them­selves and of the roof on the columns serving to keep them firmly in place.

Extant 9th and 10 Century buildings have survived more than one thousand years of aging, tempests, and other "vicissitudes," their structural designs resisting the severe winters of northern China as well as the torturing heat of the south. The old buildings have also en­dured the two most formidable natural disasters—the typhoon winds of the coas­tal areas, and earthquakes. This durability is the product of many related factors.

Since the structural framework of the roof is connected by tenons instead of iron nails, its resilience or pliancy is very great. During an earthquake, amidst the "falling heavens and cracking earth," the internal friction of each roof joint produces its own special fractional resistance. Despite the fact that the whole building will shake, internal counter movements among its parts enable the building to move with the earthquake. The finely constructed sustaining components of the roof restrain one another, braking the horizontal motion. Moreover, since the plinths are not cemented to the ground, the columns are not shattered by the horizontal movement.

The upward curve of the roof, from the eave to the ridge, is shaped by many short rafters. Such a design is to "collect sunbeams" according to "Hsi Tu Fu" (an article by Pan Ku, 32-92 A.D., who completed the History of the Han Dynasty begun by his father). The design is also to "facilitate drainage" according to Kao Kung Chi (an ancient book about all sorts of crafts). The sustaining bracket, which resists earthquake vibration, shares the weight of the huge roof. Thus, the structure is not fragile. The degree of steepness of the roof helps to guide rain water. So, the roof shape, while seeming to have mostly to do with aesthetics, actually evolved for largely practical considerations.

The Northern Sung Dynasty (960-1128) made its capital at Kaifeng. In 1085, Emperor Shengtsung died; his successor, Emperor Chetsung, pursued the task of nation-building with determi­nation and dedication. Beginning in 1093, the new Emperor initiated many imperial innovations. In December of 1097, he directed the then construction department to edit the Ying Tsao Fa Shih, a draft guide for construction (though the draft was begun in 1071 and completed in 1091, it had never been published).

The responsibility for the revision was given to Li Chieh, at that time, one of two assistant architects at the depart­ment. He completed the revision in 1100, and presented the guide to Emper­or Chetsung. The following year, the Emperor's brother, Huitsung, who was noted for his artistic accomplishments, ascended the throne, and in 1103, he ordered the revised construction guide officially published. The publication covered 36 chapters in 1078 pages, with a fore­word written by Li, and was printed by means of woodcut blocks, including illus­trations for the last six chapters. It was a very precious and unique publication; the original is no longer in existence.

In 1122, troops of the (non-Chinese) Tunguistic Dynasty of Chin (1115-1234) invaded China and captured the southern Emperors Huitsung and Chintsung. However, Emperor Huitsung's son, Chao Kou, escaped and made his way to the south of the Yangtze River, becom­ing Emperor Kaotsung in 1127, with Linan (Hangchou, Chekiang Province) as his capital. Thus the Southern Sung Dynasty began. In order to assure the standards of buildings in the new capital, Kaotsung ordered a second edition of Li's massive work, and this was completed in 1145, 20 years after the Imperial Court had moved to the south. This edi­tion, called the Shaoning Edition, was later lost. Now, only some material from the 1145 edition, supplemented by contributions of people of later generations, is available.

The original draft of 1091 which Li Chieh used as reference for editing, included much material of more ancient Chinese origin, and the 1103 edited publication presented concepts from the Han Dynasty and even from authoritative works of the Chou Dynasty (1122-249 B.C.).

In addition to the Ying Tsao Fa Shih, traditional Chinese architectural concepts can be traced through archaeology. The method of erecting wooden columns on stone plinths was in existence as early as the Neolithic Age. During the subse­quent Warring States period (403-222 B.C.), structural designs similar to that of the later bracket between the capitals and roof were depicted in painted illustra­tions on bronzeware. This design artifice was employed also on the stone beams of the Han Imperial Tombs. Therefore, it is recognized that Li's Ying Tsao Fa Shih also reveals China's oldest construction devices.

During the Sung Dynasty, due to warfare with Hsi Hsia (1032-1227, a state in the Sung Dynasty period which occu­pied part of today's Inner Mongolia and Kansu Province), the Chinese armies began to grow. The number of soldiers rose from 190,000 during the reign of Emperor Taitsu (960-975), to 820,000 during the reign of Emperor Jentsung (1023-1063). Along with local garrison militia, the number of armed men reached one million. The ensuing in­crease in military expenditures reached 80 percent of total national finance, re­sulting in major deficits. In order to boost revenues, the Court levied, under various guises, new and oppressive taxes, which led in turn to an uneasy society and numerous rebellions. At the time, the need for innovation in the social economy became most urgent.

During the reign of Emperor Jent-sung, the famed statesman Fan Chung-yen (989-1052) and others pressed reforms, but their effect was mostly focused on civil personnel affairs. It was not until the reign of Emperor Shentsung that Prime Minister Wang An-shih (1021-1086) took those further steps to implement innovations in the social economy that were to make the country rich and powerful.

Wang's "new deal" is a famous inter­lude in Chinese history. Before him, ordinary people were forced to labor at public works, such as road and palace construction, waterway cleaning or dredging, etc. Wang thought this policy too oppressive. He authorized labor duty to be replaceable by cash, such revenues being themselves devoted to wages for the carpenters, bricklayers, and other workers. He increased the incomes of low ranking civil servants, stabilized food prices, and set upper limits on inter­est for farming loans.

The Ying Tsao Fa Shih of 1091 was probably completed at the earnest behest of Wang An-shih, and then used by him as an instrument to examine the ex­penses of the construction department. In the guide, analyses of labor and raw material requirements and of calculation methods for various construction work were presented in great detail.

As a matter of fact, Ying Tsao Fa Shih was not employed just to help personnel of the construction department under­stand construction principles, or in guiding construction work, but mostly, to facilitate accurate calculation of construction accounts.

Following publication of Li Chieh's revision in 1103, Li became a prominent figure in Kaifeng, Honan Province. Li's father, Nan-kong, had already climbed to the post of assistant in charge of trans­portation for Hopei Province. Then in 1085, when only 20, Li Chieh was named to the post of chiao ssu chai lang (official in charge of sacrificial rites honoring gods or ancestors).

Li Chieh joined the construction department in its lowest position in 1092 and was promoted to assistant and direct­ed to revise the Ying Tsao Fa Shih in 1096. He completed the revision job in 1102, and was again promoted, this time to the department's second most important position. In 1105, he became the head of the construction department. He died in 1110, having supervised much of Kaifeng's public construction.

In Chapter IV of Li's Ying Tsao Fa Shih, tsai was used as a measure­ment scale for timber and was divided into eight grades. The first grade of tsai was for the construction of a tien (main hall) with 9 to 11 bays from the facade. The second grade of tsai was for the construction of a tien with 6 to 8 bays. The third grade of tsai was for a tien of 3 to 5 bays, or for a tingtang (a smaller hall) of 7 bays. The fourth grade of tsai was for a tien with 3 bays, or for a ting­tang of 5 bays. The fifth grade of tsai was for the construction of a smaller main hall with 3 bays or for a bigger tingtang with 3 bays. The sixth grade of tsai was for pavilions or smaller tien. The seventh grade of tsai was for small pavilions, for caisson ceilings inside the main hall, or for brackets.

Ying Tsao Fa Shih clearly specifies standard sizes for wooden building mate­rials. In the chapter, Rules for Structural Carpentry, he wrote, "The rules for the construction of all buildings take tsai as a base, divided into eight grades. The grade to be used is decided by the size and the type of the building."

Toukong are the elements in the three-dimensional ceiling along this columned corridor of the fine, old Wu family residence in Touliu County

According to Li's book, the width of a timber was divided into 15 fen (or 15 parts), the depth was to be 10 fen. There­fore, the fen was the smaller unit of the tsai. The rule of fen and tsai is equivalent to the module system of modem times. Li wrote in his Ying Tsao Fa Shih, "The width and depth of a building as well as the length and curve of any part of a building take the fen of the tsai as its system."

The first procedure of traditional Chinese construction usually is to fix the orientation, locating the north-south axi­ality so that the major building of a com­plex will sit to the north of the group and face south, thereby gathering the warmth of the sun in the winter and avoiding it in the summer.

Following site leveling, the founda­tion for columns around the building is made firm by filling the appropriate exca­vation with stones and broken bricks, using wooden posts to pound the loose earth and a stone roller to compact the stones and broken bricks. After the foun­dation work is done, a large stone slab is positioned at each column site.

On each stone slab, a plinth stone is set, and on this, a chih. To fix the pillar root to the chih, wooden "nails" are used, enabling replacement if the chih later decays. The columns around the hall are further stabilized by means of connecting ground-level stones, and by horizontal beams at their tops.

Columns along the front are not of the same height. The two pillars at the front-center of the main hall are the shortest, the two at each end, the tallest; the rest, gradually become taller as they recede from the center. Further, the pillars around the main hall are not strictly vertical; they incline slightly toward the center of the hall. The principle of such a design is similar to that of column-use in Greek architecture.

After the erection of the columns, brackets (toukung) are placed be­tween their capitals and the roof. The combination of these sustaining parts re­quires highly sophisticated techniques.

Stabilizing brackets and ornamental wood sculpture top a column of the old Wu family home

The bracket structure includes pieces known as tou, kung, and ang, which are connected by wooden tenons. No iron nails are used. The basic supporting block is the tou, which has four variations, namely, the lu tou, chiaohu tou, chihsin tou, and san tou. The lu tou, the biggest, is placed at the bottom of the cluster comprising the cantilever bracket. The second largest, the chiaohu tou, is placed on the end of the bracket. The third largest, the chihsin tou, is posi­tioned in the center of the kung, where another kung can be placed upon it. The smallest is the san tou, positioned at the ends of the kung, paralleling the facade.

There are five types of kung, namely, the hua kung, nitao kung, kuatzu kung, ling kung, and man kun. The hua kung is the only kung positioned perpendicularly to the facade. After the hua kung and nitao kung are combined in a crossing position, the two are placed on the lu tou. The bracing strips are secured to the nitao kung to increase the strength of the kung, two kuatzu kung then being attached to the two ends of the hua kung. Above these will be the longest kung, or ling kung. The kung at the highest level is the man kung, and on it are placed three tou (with a chihsin tou in the center, and san tou on the two ends). The three tou bear the weight of the roof purlins, which parallel the facade and are perpen­dicular to the beams.

The ang is a framing component part supported by the capital. Cantilevering out of the building, it is long and is slantly placed, being supported in position by a cuneiform-shaped component part called a shua tou. The ang's tail and middle part bear the weight of the purlins. The weight of the roof falls on the purlins.

The lowest beam of the roof is the longest, equivalent to the width of the building. Its two ends are supported by the bracket combinations at the north-side and south-side capitals. The higher the beam, the shorter it becomes. Such a design leads to the special curve of tradi­tional Chinese roofs. Purlins are placed on the ends of the beams. Then, rafters are laid on the purlins.

Since Li Chieh's time; there have been changes in the methods of construction. The structure of the bracket combi­nation in later times served, more or less, merely for decoration.

Nevertheless, and in spite of the fact that almost a thousand years have passed since Li Chieh revised the Ying Tsao Fa Shih, this intensive collection of the techniques of ancient times and its detailed rules for construction have been the basis of an unprecedented norm for con­struction quality. Although the people of later generations have not followed it exactly, the existing traditional Chinese buildings bespeak the tang ao of the past (tang ao- referring to the innermost recess of a hall, or in its symbolic mean­ing, the profundity of Li's knowledge of architecture).

—By Betty Wang/with architect Lynn Peh-nien

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