Study on the strength of a fishing boat made from plastic recycles

Ship’s strength is a very significant factor in ship design. In this research, a study of the strength of ships made of recycled plastic material has been carried out. The ship has been designed according to the needs of the load weight, passengers, propulsion system, fishing equipment and the weight of the material itself. Then the load is distributed into the design, where the profile shape and plate thickness used are assumed to be temporary. The strength of the boat analysed, and the minimum plate thickness required in the design is 10 mm with maximum strain The recycle plastic used is type 2 (HDPE).


Introduction
According to data from the Ministry of Environment and Forestry in 2016, Indonesia annually produces around 9.85 billion pieces of plastic bags. Approximately 90 thousand modern outlets generate waste. That is, the plastic waste it produces takes about 20 to 500 years to completely decompose. And if left unchecked, it will disrupt the balance of nature. One way that can be done to reduce plastic waste is to recycle it so that it can be used as an item with other functions. With the development of technology, more and more innovations are found, such as the use of plastic waste as a mixture of various handicrafts and household appliances that use plastic-based materials [1][2] [8].
The shipping industry has experienced many technological developments and many innovations in the selection of materials used for the manufacture of ship hulls. As one of the innovations used is the use of type 2 plastic material (HDPE), which, Turkey first used type 2 plastic material (HDPE) as a boat-building material. Where, type 2 plastic material (HDPE) aims to replace shipbuilding materials using fiberglass reinforced plastic (FRP), fiberglass reinforced plastic (FRP) material is considered more environmentally unfriendly than the use of type 2 plastic (HDPE) which is better and safer for humans. environment.
Because with the advancement of technology in the shipping world, the author tries to make a new breakthrough by making materials from plastic waste, using type 2 plastic waste (HDPE) which if left unchecked will damage the environment, it is hoped that this material has the advantage of being durable, resistant to corrosion for approximately 50 years to * Corresponding author : budhi.martana@upnvj.ac.id decompose, has small cracking power so that it can reduce damage, and has high flexibility so it is very suitable in case of bad weather at sea, and can be recycled again .

Literature Review
According to data from the Ministry of Environment and Forestry in 2016, Indonesia annually produces around 9.85 billion pieces of plastic bags. Approximately 90 thousand modern outlets generate waste. That is, the plastic waste it produces takes about 20 to 500 years to completely decompose. And if left unchecked, it will disrupt the balance of nature. One way that can be done to reduce plastic waste is to recycle it so that it can be used as an item with other functions. With the development of technology, more and more innovations are found, such as the use of plastic waste as a mixture of various handicrafts and household appliances that use plastic-based materials [8].
The shipping industry has experienced many technological developments and many innovations in the selection of materials used for the manufacture of ship hulls. As one of the innovations used is the use of type 2 plastic material (HDPE), which, Turkey first used type 2 plastic material (HDPE) as a boat-building material. Where, type 2 plastic material (HDPE) aims to replace shipbuilding materials using fiberglass reinforced plastic (FRP), fiberglass reinforced plastic (FRP) material is considered more environmentally unfriendly than the use of type 2 plastic (HDPE) which is better and safer for humans. environment.
Because with the advancement of technology in the shipping world, the author tries to make a new breakthrough by making materials from plastic waste, using type 2 plastic waste (HDPE) which if left unchecked will damage the environment, it is hoped that this material has the advantage of being durable, resistant to corrosion for approximately 50 years to decompose, has small cracking power so that it can reduce damage, and has high flexibility so it is very suitable in case of bad weather at sea, and can be recycled again .

Plastic
Plastics are polymers consisting of molecules called monomers which are commonly known as comonomer, if they meet different types of monomers, they are called copolymers. There are types of natural polymers that we are familiar with such as: cellulose, protein, natural rubber etc. However, natural polymers only survived in the 19th century and beyond, polymers experienced a fairly rapid development until for the first times polymers from nitrocellulose were distributed to the public until now used in household appliances etc [2] [6]. The types of plastics can be seen. in below figure. Type 2 plastic (HDPE) is a type of plastic that has the ability to prevent chemical reactions between the plastic packaging and the packaged food or beverage. HDPE also has the characteristics of being stronger, harder, opaque, and resistant to high temperatures. Because HDPE is made from petroleum, to make 1 kg of HDPE requires around 1.75 kg of petroleum as the raw material for its manufacture. We can find many types of HDPE plastic in our daily lives, such as: shampoo packaging, plastic bags, milk packaging, plastic rolls and others, the HDPE manufacturing process is made with a catalyst process. Because, type 2 plastic (HDPE) is a type of plastic that can be recycled, therefore, the processing process is by first sorting it from other types of plastic. After that, the process of crushing type 2 plastic (HDPE) in the recycling plant. Then, the smelting process is the last process of a product can be seen in below figure [2][4].

HDPE Boat
Some countries have applied HDPE as material for small boat, like Turkey, Germany and other. The application has success by use virgin HDPE variant like sheet HDPE, powder or granule. And this method also has conducted in Indonesia for 5-6 six years ago. There are some advantage use HDPE as main material for small boat; not corrosive, good in impact, small resistance (low roughness resistance), easy to make and assembly, low maintenance and 100% recycle [9][5] [3].

Methodology Research
Noverdo et all [9] has tried to applicate recycle HDPE into non class boat. The methodology will apply in this research as follow chart

Tensile Test
The test aims to determine the strength of the material based on the resistance of a material to the tensile load of a test material. Tensile testing is carried out by adding the load slowly, which then increases in length which is proportional to the working force. Materials that cannot withstand relatively low stress are brittle materials.

Bending Test
This test can also be referred to as testing the flexibility of the material to a centre of gravity attached to two supports. Tests are carried out to determine whether the material is deformed or not by two opposing forces at the same time E3S Web of Conferences 328, 0 (2021) ICST 2021

Impact Test
This test is carried out to determine the brittleness or ductility of a material to be tested by sudden loading with static test equipment.

Design of Test Specimen
The specimen design used is in accordance with the ASTM standard. For tensile test using ASTM D368, bending test using ASTM D790 3, and impact test using ASTM D256.

Experimental Tools
The following are the tools used and have international standards and have been calibrated  (4a-4d). The larger result is 22,091 and minimum is 22,774. As per above data, it was obtained that the larger stress was found in the specimen with a ratio of 90%: 10% for type 2 plastic (HDPE) with the addition of resin. Detail stress and strain every specimen test, please see below graphic.  Bending test of type 2 recycle plastic (HDPE) and resin with a ratio of 97.5%: 2.5% resulted in different bending strengths of 4 test specimens (1a-1d). The larger result is 25,595 and minimum is 26,5. Bending test of type 2 plastic (HDPE) and resin with a ratio of 95%: 5% resulted in different bending strengths of 4 test specimens (2a-2d). The larger result is 27,295 and minimum is 28,213. Bending test of type 2 plastic (HDPE) and resin with a ratio of 92.5%: 7.5% resulted in different bending strengths of 4 test specimens (3a-3d). The larger result is 28,43 and minimum is 29,867. Bending test of type 2 plastic (HDPE) and resin with a ratio of 90%: 10% resulted in different bending strengths of 4 test specimens (4a-4d). The larger result is 31,56 and minimum is 30,362. After described above, it was obtained that the larger stress was found in the specimen with a ratio of 90%: 10% for type 2 plastic (HDPE) with the addition of resin. Detail stress and strain every specimen test, please see below graphic.   Impact test of type 2 recycle plastic (HDPE) and resin with a ratio of 97.5%: 2.5% resulted in different impact strengths of 4 test specimens (1a-1d). The larger result is 1,6012 and minimum is 1,6915. Impact test of type 2 plastic (HDPE) and resin with a ratio of 95%: 5% resulted in different impact strengths of 4 test specimens (2a-2d). The larger result is 1,2415 and minimum is 1,38. Impact test of type 2 plastic (HDPE) and resin with a ratio of 92.5%: 7.5% resulted in different impact strengths of 4 test specimens (3a-3d). The larger result is 0,9649 and minimum is 0,8267. Impact test of type 2 plastic (HDPE) and resin with a ratio of 90%: 10% resulted in different impact strengths of 4 test specimens (4a-4d). The larger result is 1,6915 and minimum is 1,6012. After described above, it was obtained that the larger stress was found in the specimen with a ratio of 97.5%: 2.5% for type 2 plastic (HDPE) with the addition of resin. Detail stress every specimen test, please see below graphic.

Strength of Fishing Boat
Modelling of fishing boat has been carried out used sample of Maxsurf model include frame, stiffener and web frames. This boat has designed for 3 GT of fishing vessel with hull thickness, web frame and stiffener approximate 10 mm. After input all recycle material data into the software, strain of hull can be as per below figure