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Chapter 29 "Regulations of Qing-style Construction" Introduction (2)
The method used to frame the wooden frame is to form a room around the upper ends of the four columns with two beams and two beams.Then set up a stacked beam frame on top of the two beams to support the truss; the truss passes through the left and right ends of the room, and descends step by step from the top of the beam frame to the front and rear squares.The tile slope curve is thus determined.The rafters are nailed to the trusses, and the rows are juxtaposed, and the lookout boards are used; the tiles are laid above the lookout boards, which is the simplest way to say that the frame is the backbone.This "room" is a unit of Chinese architecture; every building is composed of one or more rooms.

The impact of this architectural approach on its appearance is most obvious in the following points:
([-]) The height is limited by the length of the wood, and never exceeds the possible range of the wood.If there are buildings with a height of more than two floors, each floor forms a frame by itself, which is stacked on top of each other, such as the stacked columns of Greece and Rome.

([-]) Even a very solemn building also presents an absolutely exquisite appearance.Structurally, regardless of the size of the building, there is absolutely no need for a strong and thick load-bearing wall, unless it is deliberately thickened for the purpose of expressing majesty, such as city towers and other buildings.

([-]) The size of doors and windows is not limited; light-transmitting small wooden works such as door screens and window sashes can be installed between columns to allow sufficient light in the room.Unlike the doors and windows of a stone building, which are holes in the load-bearing wall, the size of the doors and windows is inversely proportional to the strength of the wall.

([-]) The stacked beam frame is increased layer by layer, forming a "lifting frame method", so that the roof tile slope is natural, and the structure obtains a special oblique curve.

four

The most notable and unique feature of Chinese architecture is the transitional bucket between the roof and the columns.The rafters are eaves, and the eaves are supported on the eaves. In order to make the eaves protrude far, overlapping curved woods--warped--outward are used to support the eaves.In order to reduce the shear force at the intersection of the truss and the warp, the curved wood with the cross at the warp head——.At both ends or at the intersection with the warp, use a bucket-shaped wooden block - a bucket - to support between the upper and lower layers or warp.Most of the curved wood and bucket-shaped wooden blocks are combined to support the protruding eaves, which is called a bucket.

The function of the bucket under the eaves is to gradually concentrate the weight of the eaves until it reaches the top of the pillars.But the bucket is not limited to the eaves, it is also used on the pillars inside the building, so the bucket is the most important joint between the horizontal structure and the column, regardless of the inside and outside.

In the evolution of Chinese architecture, the changes in the dou are extremely significant, and it can mostly represent the degree and trend of architectural skills in various periods.We do not have the earliest wooden buckets, but judging from the imitation wooden Han stone que, this kind of bucket is obviously much simpler than the later generations;Not only do we not see the warping of outward expenditure, but even compared with the simplest "one bucket and three liters" in the Qing style, the middle one liter has not been formed (although there is, it is only a small bucket between the two ends).It was not until the front gate of the Tianlongshan Grottoes in Ruyungang, Northern Wei and Northern Qi that there was a system of fighting statues with one bucket and three liters today.The bucket painted on the lintel of the Tang Dayan Pagoda's stone carvings gives us evidence that in the Tang Dynasty there was a warp (called Hua in the Song Dynasty) that extended outwards in the front, and it was double-layered.What we know about the shape of the bucket in the Tang Dynasty is not limited to the stone carvings of the Big Wild Goose Pagoda. Jianzhen built the Golden Hall of Toshodaiji Temple in Nara.The most organic part of the evolutionary bucket, "ang", is also seen here for the first time.

The oldest bucket structure we know in China is the Guanyin Pavilion of Dule Temple discovered by Sicheng in Ji County, Hebei the year before last. The pavilion was built in the early Northern Song Dynasty ([-] A.D.). It can be seen at a glance that it is an organization with functions and functions.

The two ridges in this bucket rise obliquely, protruding outwards to support the far-reaching eaves, and the rear tail is inclined to support the bottom of the beam. Therefore, there is a kind of stress on this bucket; , the front eaves are the load, and the weight on the golden trusses at the back and tail is pressed down to maintain its balance.The bucket becomes an organic structure that can carry the load of the roof.

Judging from the overall appearance of the building, the Guanyin Pavilion of Dule Temple is very similar to the murals of the Five Dynasties in Dunhuang, and the structure and distribution of Liandou are also very similar.Taking this as an example of the oldest fighting, and following the steps of the evolution of fighting with the times, we can see a certain tendency, so we can determine the status of Qing style fighting in terms of structure and art.

Figure [-] on the next page is a comparison of Liao, Song, Yuan, Ming and Qing Dynasties. You can see that ([-]) from large to small; ([-]) from simple to complex; ([-]) from majestic to delicate; ([-]) from structural to Decorative; ([-]) The part that is carved from the real structure, such as Angbu; ([-]) The distribution is from sparse to dense.

Dou a and b in the picture are both objects from the reign of Emperor Shengzong of the Liao Dynasty, which can be said to be the works of the early Northern Song Dynasty.

Its height accounts for about half to two-fifths of the column height.

The f-pillar is the same height as the b-pillar, and there is more than one step on the outside of the bucket. According to the size of the "Engineering Practice Regulations", the bucket height is only a quarter of the column height.However, other buckets such as c, d, e, and f in the Liao and Qing Dynasties, the ratio of the height of the bucket to the column is too small.As true in scale as it is in actual size.As a result, the buckets of later generations became more and more complicated and delicate, and the function of buckets gradually disappeared. For example, buckets were originally used to support the eaves, but in the Qing Dynasty, the eaves beams were placed on the beam heads, and the distance of its expenditure did not depend on the expenditure of layers. The curved wood (warped or Ang).The Liao Song Dou, as shown in the pictures a to d, is an organic structure, which is responsible for bearing the load of the eaves and the roof.After the Ming and Qing Dynasties, except for those on the column caps that still have considerable structural functions, their flat body has become a semi-decoration.As for the distribution of buckets, as can be seen in Tang paintings and Dule Temple, only one Bujian bucket (known as Pingshenke in the Qing Dynasty) is used between the capitals of the columns; , use a flower every now and then.In the Ming and Qing Dynasties, the doukou was divided into [-] points. Between the two pillars, eight blocks of flat body can be used. The dense arrangement not only has no structural value at all, but also becomes a heavy burden on the architrave itself. Compared with Song Jian , the majesty and heroism are too different.

Regarding the mechanical problems of beam frame materials, the Qing style is relatively ancient and the modern common structural method has a significant shortcoming.In modern wooden beams, the ratio of beam height and width is usually two to one or three to two, in order to achieve the most economical and effective trade-off.Song "Zao Fa Shi" also stipulated that the ratio of three to two. The "Engineering Practice Regulations" set the ratio of ten to eight or twelve to ten, and its cross-section is almost square, which is an unscientific and uneconomical method of using materials.

The roof has always been regarded as a very peculiar and mysterious Chinese roof curve. In fact, it is just the result of the straightforward and natural structure. There is nothing beyond the principles of mechanics and artificiality. At the same time, it is extremely successful in both practicality and aesthetics.The whole curve and outline of this kind of roof, the upper part is towering and towering, and the eaves spread lightly like wings, making the originally boring and clumsy practical part a beautiful crown of the whole building, which is a feature that other buildings do not have.

Due to the practical problems of rain and light, the roof has already expanded to the eaves.The eaves are far away, and the edge of the eaves is also under low pressure, which hinders the light, and the rainwater flows rapidly, and the problem of splashing water also occurs under the eaves.In order to solve these two problems, there was the invention of cornices: double-layer rafters were used, and the upper rafters were slightly curved, so that the edge of the eaves was slightly turned upward into a curve.When it reaches the corner of the house, it is raised to the left and right at the same time, so that the eaves at the corner of the house will be even more curved.This "curling of the wing corners" is a very reasonable and natural arrangement in terms of structure. We can actually say that the warping of the corners of the house is caused by the structural law.Because the main member at the intersection of the two eaves at the corner—the "corner beam" and the upper section "youjiao"—is a much larger timber than the rafters, and its direction is 45 degrees to the front of the building, so The row of rafters, which are at right angles to the front of the building, must gradually diverge when they reach the corner of the house, so that the asymmetry is parallel to the corner beam, and the last one must be close to the corner beam.However, because the size of the rafters is different from that of the corner beams, in order to make the upper skins of the rafters and the corner beams level to form the watchboard, the rafters must be lifted up one by one, and "pillow wood" should be placed underneath.All these are structural problems that are appropriate and solved by techniques.

This curve is almost unbelievably simple and natural in structure; at the same time, it adds a lot of charm in aesthetics.However, we must pay attention to excessive or extreme tendencies, which often turn the originally natural and reasonable structure into trickery and complexity.This excessive tendency, on the surface, presents a weakness of fragility and hypocrisy, which is not acceptable to aestheticians.However, most people often think that the more ingenious and complex the more beautiful, they encourage this tendency invisibly.Where the craftsmanship is flexible in the south, the cornices and raised corners are particularly appropriate. Although the appearance has a romantic posture, it is easy to attract praise, but it is not as solemn and appropriate as is common in modern times in the north, which meets the pure aesthetic requirements.

The curve of the roof is not limited to the "curved wing angle" and "flying eaves", that is, the entire tile slope is also slightly curved, not a straight slope; Lift the frame" to make the slope of the roof steeper as it goes up, and gentler as it goes down. "Kao Gong Ji" "...Where people make the cover... If the superior wants to be respected, but the universe desires to be humble, and if the superior is respected and humble, then he will spit water and slip away", which clearly explains the actual effect of this kind of roof.

In terms of appearance, because of this "superior and inferior", the tendency of the original roof ridge to be reduced due to perspective can be corrected, so that the roof still stands tall and the beauty of the appearance is increased.

(End of this chapter)