大棚合成木塑骨架力学性能研究

发布时间：2018-04-27 18:44

  本文选题：合成木 + 木塑　； 参考：《西北农林科技大学》2015年硕士论文

【摘要】：合成木塑是目前研究比较热门的新型材料,它是利用废弃塑料和农业副产物植物秸秆等合成的一种环保节能材料。西安鸿晨环保科技有限公司首次将合成木塑用于搭建温室大棚。目前合成木塑存在的主要问题是:合成木塑骨架物理性能不清楚;夏季高温季节合成木塑骨架软化散失承载力。本研究主要研究以下几个方面:1.合成木塑骨架力学性能测试,主要测试合成木骨架的抗压性能、抗拉性能、弯曲性能、握螺钉力、抗荧光老化性能、抗冲击性能;2.合成木塑骨架大棚实际承载力试验;3.合成木塑骨架双膜大棚实际使用情况调查;试验后得出如下结论:1.合成木塑材料的抗拉、抗压、抗弯性能都与温度呈负相关,温度对合成木塑材料力学性能的影响表现为极显著。2.合成木塑骨架中植入钢带可以大大增强骨架本身的承载能力和材料各种条件下的极限应力。合成木塑骨架在下表面植入打孔钢带之后材料由脆性断裂转变成韧性断裂,这大大增加结构的安全性。3.合成木塑骨架材料植入打孔钢带对材料力学性能提高极显著,但打孔距离对材料力学性能的影响不明显。4.合成木塑骨架中植入打孔距离为10cm的钢带时骨架性能提高56.00%,使用试验改进的合成木塑骨架搭建大棚,骨架实际承载力提升29.7%。5.合成木塑骨架大棚在以后设计过程中,只要跨度超过8m一定得加立柱,不然会出现结构性失稳。6.骨架的握钉力(1510N≥800)和抗冲击性能(无破裂)都达到了国家对合成木塑材料的技术要求。7.合成木塑大棚骨架材料在0.244KN/m2的荷载作用下,已经达到材料正常使用极限状态,不适于继续承载。8.合成木塑骨架材料植入打孔钢带后最大弯曲应力波动性变小,没有植入钢带时骨架的弯曲应力波动范围在-29.50%~23.30%,骨架下表面植入钢带后弯曲应力波动范围在-18.91%~19.28%,骨架下表面植入打孔钢带后弯曲应力波动范围在-5.38%~4.95%。
[Abstract]:Synthetic wood-plastic is a new kind of material which is very popular at present. It is a kind of environmental protection and energy saving material synthesized from waste plastic and agricultural by-product plant straw. Xi'an Hongchen Environmental Technology Co., Ltd. used synthetic wood and plastic for the first time to build greenhouses. At present, the main problems of synthetic wood-plastic are that the physical properties of synthetic wood-plastic skeleton are not clear, and the softening and dissipating capacity of synthetic wood-plastic skeleton is not clear in summer high temperature season. This research mainly studies the following aspects: 1. The mechanical properties of the synthetic wood-plastic skeleton were tested. The compressive, tensile, bending, screw holding, anti-fluorescence aging and impact resistance of the synthetic wood skeleton were mainly tested. Experimental study on the actual bearing capacity of synthetic Wood-plastic Skeleton shed. The actual use of the composite wood-plastic skeleton double film greenhouse was investigated, and the following conclusion was drawn after the experiment. The tensile, compressive and bending properties of the synthetic wood-plastic materials are negatively correlated with the temperature, and the effect of temperature on the mechanical properties of the synthetic wood-plastic materials is extremely significant. The steel strip implanted in the synthetic wood-plastic skeleton can greatly enhance the bearing capacity of the skeleton itself and the ultimate stress under various material conditions. After the composite wood-plastic skeleton was implanted with perforated steel strip on the lower surface, the material changed from brittle fracture to ductile fracture, which greatly increased the safety of the structure. The mechanical properties of the composite wood-plastic skeleton material were improved significantly by inserting perforated steel tape, but the effect of drilling distance on the mechanical properties of the material was not obvious. The performance of composite wood-plastic skeleton was improved by 56.00 when the steel strip with perforating distance of 10cm was implanted into the composite wood-plastic skeleton. The experimental improvement of the composite wood-plastic skeleton was used to build the shed, and the actual bearing capacity of the skeleton was increased by 29.77.5. In the later design process of the composite wood-plastic framework shed, columns must be added as long as the span exceeds 8m, otherwise the structural instability will occur. 6. The holding force of the skeleton is 1510N 鈮，

本文编号：1811869