Longba Town is composed by 19 villages, which do not possess a decent market. Groceries are locate along the the town's only main road, and livestock are often slaughtered in the streets, spilling blood on the ground directly.
Face such a situation, the government has set aside a small plot of vegetable land to build a market of about 2,500 square meters, which provides a high-quality shopping environment for residents, as well as hosts the annually festival and other activities. Therefore, it is not only a daily market serving the town, but also a festive place radiating the whole county. It should be convenient and comfortable, and also, it needs to have certain publicity.The site environment is intricate but also interesting：Two rows of houses in the southeast encompass the site tightly; a canal winds its way to the northwest, leaving a zigzag outline of the land. In this regard, we adopted a design method from the inside out, starting from the center of the site, and then gradually to the outside, slowly infiltrate into the surrounding irregular corners to go. Firstly, an array of 25 standard selling units was arranged, which occupied the center of the site to establish order.
Then, the outer units were changed into rooms facing inward to complete the closure of the space and define the basic boundary of the building. Finally, it makes use of other auxiliary functions to "push hands" with the complex surrounding environment：The front square is enclosed by a low wall at the main entrance, and the gaps between houses are filled gently. The garbage and toilet are located in the north far away from the residential area, sticking out of the main building in the direction of the canal. In addition, the original height difference of the site is directly maintained. The whole base has a slope of 1:60, which not only reduces the earth volume, but also facilitates the cleaning work in the future operation.
The prototype commonly used in market architecture is a uniform space or unified space composed by a big roof and neutral supporting members. This project tries to make the market space correspond to the buying and selling behavior, to incorporate the space, behavior, structure, light and other elements together, so as to produce a more intense and dramatic expression.
Corresponding to the behavior of buying and selling, two different Spaces are shaped and juxtaposed: the seller's space has a higher headroom, the columns encloses a square sales area with stalls in four directions. It forms a dramatic stage-like display effect with the skylight shed from the top. On the other hand, the surrounded buyer's space has a net height which reduced to 3.5 meters, turning into a kindly scale. Viewed from the outside, it appears as 14 small lighthouses protruding from the roof.
The market is mainly built of steel structures. The double-clamped c-type steel beam is adopted to rivet on the steel column from both sides. The main beam and the secondary beam are staggered in height. This way of connection is not only convenient for construction, but also makes the components remain independent and complete, so that the structural logic is clear and easy to read.
The original idea was to add a metal mesh ceiling under the beam, hoping to keep a certain balance between the abstract space and the expression of construction, but eventually it was cancelled due to the limitation of the cost. In order to ensure the slender diameter of the column within 100mm, the structural engineer set the bottom line of the column distance of 4500mm and the cantilever of 3000mm. Under this framework, we constantly adjusted the plane, in order to make the neat column network coexist with the irregular architectural outline and the curved partition wall harmoniously.