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This study examined the uplift bearing capacity of spiral steel pegs according to the degree of soil compaction and embedded depth in a small-scaled lab test. As a result, their uplift bearing capacity increased according to the degree of soil compaction and embedded depth. The uplift bearing capacity under the ground condition of 85% compaction rate especially recorded 48.9 kgf, 57.9 kgf, 86.2 kgf and 116.6 kgf at embedded depth of 25 cm, 30 cm, 35 cm and 40 cm, respectively, being considerably higher than under other ground conditions. There were huge differences in the uplift bearing capacity of spiral steel pegs according to the compaction conditions of ground. Their maximum uplift bearing capacity was 116.6 kgf under the ground condition of 85% compaction rate and at embedded depth of 40 cm, and it is very high considering the data of spiral steel pegs. It is thus estimated that wind damage can be effectively reduced by careful maintenance of ground condition surrounding spiral steel pegs. In addition, spiral steel pegs will be able to make a contribution to greenhouse structural stability if proper installation methods are provided including the number and interval according to the types of greenhouse as well as fixation of plastic film. The findings of the study indicate that the optimal effects of spiral steel pegs for greenhouse can be achieved at embedded depth of more than 35cm and compaction degree of more than 85%. The relative density of the model ground in the test was 67% at compaction rate of 85%.

This study focuses on the analysis of the effect of meteorological disasters on film plastic greenhouses by typhoons, heavy snow, strong wind, and heavy rain. The data of meteorological disasters from 1998 to 2015 were analyzed on provincial basis to calculate the damage rate depending on the weather cause. The cumulative damage area is 20 279 hm 2 . The damage rates of typhoons, heavy snow, strong wind, and heavy rain are 46.4%, 47.4%, 2.5%, and 3.8%, respectively. The damage index of the greenhouse, which is the ratio of the greenhouse area to the cumulative damage area, was proposed to estimate the disaster risk for 17 administrative districts. The damage index data and the cumulative damage areas were divided using the Jenks' Natural Breaks method. The average damage index is 0.66, and the damage indices are high in the metropolitan cities.