| With four different models of low carbon steel material as test materials, its mechanical properties yield strength, tensile strength, hardness, and in the normal aging, water conditions, the tensile and compressive strength and hardness of the changes of design were studied. And the performance of GP-C9.632-â…¡model of load capacity and shelter in the facilities, humidity, temperature, soil temperature and illumination change characteristics and the influence on cultivation of pepper were researched. The results showed as follow.1.With the increase of steel, steel grade of material mechanical properties are gradually increase the strength and hardness, into positive increased, but the elongation is gradually reduced.A3 was suitable to processing for its better performance function of seamless steel tube in the aspects of strength, plasticity and toughness; A4 and A5, which were high strength, high yield point, less toughness, hard to processing and modeling , were not suitable for processing remolding materials.2.The corrosion of high temperature and high humidity to steel materials had more influence than the corrosion of high heat air. After high temperature and high humidity treatment to 24h, the tensile properties, the compression performance and hardness were occupied to normal state 38.07%, 34.81% and 41.84%; after hot air aging, the tensile properties, compression performance and hardness were occupied to normal state 95.14%,95.31% and 89.36%. The corrosion protection measure was very important to increase of service life and loading capacity.3.Compared to GP-C4.525 and GP-C6.325, the GP-C9.632-â…¡had great improvement in span and space. But the design was unreasonable from the analysis of the bolts on snow load and shed load resistance in shape, and it needed improvement and optimization.4.With the expansion of space, the temperature change curve had a stable fluctuation. From this perspective, the GP-C9.632-â…¡can improve the winter night temperature and facility the heat preservation.5.In the daytime sunny situation, the soil temperature variation was diminishing gradually as the greenhouse soil depth increase, and the time of high temperature was delayed. There was remarkable correlation between shallow soil temperature and 150cm air temperature. The change rule was similar, but there was to some extent hysteresis. With the increase of trellis space, the range of temperature variation was diminished; with the increase of depth of soil, the size effect by trellis was induced gradually. 6.The humidity changes in greenhouse had change rules of season and day. With the rise of temperature, saturation vapor pressure increases and humidity decreases. Conversely, humidity would rise. Humidity had different changes in different greenhouse. After comparison, the GP-C9.632-â…¡had a large space, and the internal environment was less affected by external effects. The range of humidity change was the least, but the overall change rule was the same.7.Through the analysis of light intensity and shed light transmittance of different structure, the light transmittance of GP-C4.525, GP-C6.325 and GP-C9.632-â…¡were 73.21%, 59.61% and 52.00%.The GP-C9.632-â…¡,which had a low light transmittance and low light intensify, cannot satisfy the pepper growing demands. The net photosynthesis rate trend was bimodal curve and had a previous midday photosynthetic phenomenon.8.Comprehensive studies showed that the GP-C9.632-â…¡which had a not reasonable structure and shape needed improvement and optimization. Assuming that the greenhouse span was 960cm, the roof high and shoulder high should be 300cm and 120cm. According to the principle of aerodynamics, the arc point high parameter of outer and inner contour should be determined. According to the actual situation, the suggestion were given on internal tent pole roughness and arc spacing.
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