The history of granary development

In modern China, wars continued, political power was unstable, agricultural production was greatly damaged, grain output was very low, and there was a serious shortage of grain. Therefore, the development of grain storage technology and barn construction is slow. When New China was founded, the national treasury capacity was only12.6 million tons. Moreover, most warehouses are very simple, often with brick-wood structure and bamboo-wood structure, and the storage capacity of each warehouse is only 30,000-60,000 kilograms. At the same time, some warehouses are ancestral halls and temples that have been transformed, and the storage conditions can not meet the requirements.

During the period of 1955- 1960, the mechanized warehouse of the Soviet Union, that is, the "Soviet warehouse", was introduced into the grain warehouse in the form of learning from the Soviet Union. This type of warehouse is widely promoted and built in China, with brick wall, 5m- 1m-5m three-span wooden frame (with two wooden pillars in the middle), 3 m bay, 54 m long bay, 2-2.5 m high grain piled on the eaves, and 2,500 tons of bay storage capacity (then called 5 million Jin warehouse). The standard "Soviet-style warehouse" considers mechanized operation. There is a 2.0×2.0-meter trench in the middle of the wooden frame, which contains a grain belt conveyor. Due to the poor economic strength at that time and the shortage of steel and rubber raw materials, overpasses and trenches were cancelled when the "Soviet warehouse" was built later, and the warehouse became a "standard warehouse".

During the period of 1964- 1974, according to the requirements of combat readiness, a number of granaries were built in some mountainous areas and remote areas on the principle of "concealment, dispersion, relying on mountains and mobility". Later, due to various reasons such as grain source and transportation, grain was rarely loaded. At the same time, some small warehouses with brick and wood structures and "round warehouses" have been built all over the country. In Henan, Shaanxi, Shanxi, Inner Mongolia and other loess plateau areas, a number of underground trumpet warehouses and cave warehouses have been built. These underground warehouses are adapted to local conditions, with low cost and safe and stable grain storage, which has formed a major feature of granaries in China.

During the period of 1975- 1983, the main warehouse types were static chamber warehouse, load-bearing brick wall and concrete floor, and the grain loading height was 3-3.5 meters. The main roof structures used are reinforced concrete composite roof truss, reinforced concrete portal steel frame and prestressed reinforced concrete arch slab roof.

1983- 199 1 year, according to the development of agriculture and grain, the State Council approved the construction of "three warehouses" of grain depot, cotton depot and fruit depot in1983+0/kloc-0, which is the first time since "Suku". The warehouse type is still mainly room warehouse, and the structure is mostly brick-concrete structure, but the grain loading height is generally 4.5 meters to 5.0 meters, and the warehouse span is mainly 18 meters and 20 meters.

1992- 1997 in order to promote grain circulation and improve the mechanization degree of storage operation, 18 mechanized backbone grain depot built nationwide in 1992 and the project of improving grain circulation in China by using World Bank loans are a new starting point for China granary construction.

During the period of 1998-200 1 year, the warehouse directly under the central government was built with a storage capacity exceeding 1000 billion Jin, which is an unprecedented large-scale warehouse construction. This time, the warehouse is mainly house warehouse, and other warehouse types are shallow round warehouse and vertical silo.

The history of granary construction for more than 50 years has accumulated rich experience in granary construction, but there are also many painful lessons. The granary construction should put the full guarantee of grain storage safety in the first place, and meet the needs of grain storage safety from the physical, physiological and ecological characteristics of grain itself. The choice of warehouse type should be based on local conditions, and the suitable warehouse type should be determined according to the climatic conditions, geological structure, grain characteristics, grain storage properties and functions of each region, so that it is not possible to make a "one size fits all" across the country; The building structure and materials of granary should be selected according to the economy of opening granary and the safety of grain storage, so as to gradually improve the comprehensive performance of granary in China.