Abstract—The purpose of this study is to design fasteners of the simplified greenhouse by using rods made by recycled composite materials. The design process was composed of drawing the 3D model of the fastener and simulating torsion and tension forces caused by the 11-level wind to determine whether the strength of the designed fastener was sufficient. During the analysis, it was found that the material of stainless steel could increase the joint strength of the overall simple green house structure, which compensated the lack of strength of the rods. There was only a slight displacement and deformation at the joint of the fastener and the extent of deformation and displacement was insufficient to induce the fracture of the rods. Therefore, the designed fastener was able to tolerate most of the wind in the real world. The results of this study will contribute to the application and promotion of using rods made by recycled composite materials in the simplified greenhouse. Index Terms—Fastener, simplified greenhouse, recycled composite material. I. INTRODUCTION Crops are indispensable parts of our lives nowadays. They are not only the fruits and vegetables we eat in daily life, but also have high ornamental and economic values. However, these high-value crops require more careful care and delicate environment than general crops. In order to achieve this cultivating condition, greenhouses are necessary. In the past, the greenhouse was to maintain the environment for planting. Under the protection, plants could be protected from external environmental influences, excessive water loss could be prevented, and temperature and humidity could be controlled. However, the price of a greenhouse was very expensive. Therefore, it was not economic to grow general crops in the greenhouse. Recently, a simplified greenhouse has been developed, which can provide shelter from wind and rain as well as avoid insects. The price is also lower. Therefore, it is more adopted by general farmers. The design requirements for standard greenhouses can be found in the documents provided by the National Greenhouse Manufacturers Association (NGMA) [1]. Documents published in 2010 provide provisions for greenhouse loads Manuscript received June 15, 2019; revised September 5, 2019. This work was supported by Ministry of Science and Technology, R.O.C., for financial support (MOST 107-2321-B-020-002). Cheng-Jung Yang and Ci-Hao Wang are with the Department of Mechanical Engineering, National Pingtung University of Science and Technology, 1, Shuefu Road, Neipu, Pingtung 91201, Taiwan (e-mail: cjyang@mail.npust.edu.tw, deathless9227@gmail.com). Ying-Chieh Lee is with the Department of Materials Engineering, National Pingtung University of Science and Technology, 1, Shuefu Road, Neipu, Pingtung 91201, Taiwan (e-mail: YCLee@mail.npust.edu.tw). Meng-Hao Tsai is with the Department of Civil Engineering, National Pingtung University of Science and Technology, 1, Shuefu Road, Neipu, Pingtung 91201, Taiwan (e-mail: mhtsai@mail.npust.edu.tw). based on corresponding standards and minimum design loads for structures [2]. In addition, the EU's construction of standard greenhouses follows EN-13031-1, which provides rules for the design of greenhouse structures specific for professional production of plants and crops [3]. The functions of the greenhouse structure, including mechanical resistance, durability, applicability, and stability, is followed by Eurocode 1, ENV 1991-1 [4]-[6]. If the greenhouse structure is made by steel structure, Eurocode 3, ENV 1993 [7], can be referenced. The destruction of the greenhouse structure is mainly due to climatic behaviors, such as the movement of the rod, the bending of the arches, the failure of the covering net, uplifted foundation posts and the failure of the fastener [8]. In order to reduce the mistakes in greenhouse design, many researchers have used computer computing methods to analyze structures, loading and environments [9]-[11]. There are a lot of cases in which composite materials are applied in engineering, and some technologies are mature. For example, in the case of vehicle engineering, a composite frame can achieve less weight than general iron metal and achieve greater safety for passengers [12]. Another application is to extend the life cycle of vehicle parts. It is easy to disassemble when the parts go to the waste recycling stage, and improve the recovery rate of the basic parts [13]. Composite materials can also be used in windows as an energy saving tool. A recent research report points out that giving a composite coating on the window surface produces an infrared light-shielding effect that can increase the overall energy efficiency of the building by 40% [14]. Many plastic products are produced currently. Unfortunately, mostly plastic products cannot decompose or disappear in the general natural environment, causing environmental impacts and damages. In order to promote environmental protection, these plastic products have also been recycled into many recycled products recently. These industrial products made of recycled materials also have certain strength and practicality, and their weight is lighter than that of ordinary steel pipes. Some of the buildings in the market now also use these recycled plastic composites. Therefore, the use of a variety of recycled plastics as a new material for product design has gradually become a trend. The plastic wire required for 3D printing in the FDM process has been studied by many people. The advantage is that this composite material can be utilized in the future customized market [15]. It also happened on railway transportation. A team made track fasteners from recycled plastics for mechanical analysis and understanding the feasibility of the application [16]. Based on the recycled materials, this study develops the fasteners assembled in a simplified greenhouse with light weight and simplicity to assemble, which fits the need for general household planting. Recycled Plastic Composite Rod-Based Design of Fasteners in the Simplified Greenhouse Cheng-Jung Yang, Ci-Hao Wang, Ying-Chieh Lee, and Meng-Hao Tsai International Journal of Materials, Mechanics and Manufacturing, Vol. 7, No. 5, October 2019 210 doi: 10.18178/ijmmm.2019.7.5.461