Tuesday, March 31, 2009

Wooden house of Minahasa an earthquake resistant construction

An earthquake resistant house designs have been a compulsory construction for home owners living in the ring of fire areas such as Indonesia, Malaysia, the Philipine and Japan. Just building a concrete houses will not be enough. Architects who design earthquake resistant houses must add steel frames inside the concrete beam and columns to reinforce them. A building information modeling software such as Archicad and Revit must equip themselves with structural analysis features. So far, only Revit from Autodesk that has got the structural features which can help architects design and analyze the structure of buildings.



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For traditional wooden houses, the material which is mostly used is of course the wood. Wood if well preserved and dried is one of the best construction materials for houses.


In Minahasa of North Sulawesi, people build houses mainly from wood. Minahasa is a region in northern part of Sulawesi island. There are a number of active volcanoes which often erupt and cause earthquakes. So, the house construction there is mostly made from wood.


The kinds of wood which Minahasan people use are coconut, lingua, cempaka and sometimes besi or merbau. Old coconut tree which is not productive anymore in producing palm oil will then be cut and converted into home building material.


The wooden house of Minahasa looks beautiful in terms of their architecture. Architecture is the art and science of buildings. Although the traditional builders of Minahasan wooden houses have never taken any formal education, their designs are really environmentally friendly and united with the nature. Tourists who visit Minahasa often buy these wooden houses in Woloan village. This village has exported their knock down wooden houses to many countries around the world.


Wooden house can be one of the best home materials due to its earthquake resistant properties but it is not fire resistant. To minimize the risk of burning, architects must apply new design approach to their wooden house by applying fire resistant materials to some parts of the house. This can include fire resistant drapes and wall paper, as well as kitchen room made of ceramic materials.


When the new approach has been applied to the design of an earthquake resistant Minahasan house, it will be able to enter wider market of worldwide wooden house trade. I hope. by Charles Roring in Manokwari of West Papua - Indonesia, blog directory

Monday, March 30, 2009

Wooden house and alleyway of Kyoto

Japanese have been famous for their house design for years. Whether you are an architect who designs a house by drawing it manually or drafting it with Archicad 12 of Graphisoft, when you design an earthquake resistant house, you need to learn more about Japanese wooden house. The style of the house is simple. Its construction does not have rounded wall. Most of the walls are straight ones with partitions from thick white paper. Temples have rounded or curved roofs. The floor is covered with special mat made of rice straw and dried woven grass called Tatami. When we walk on the Tatami, we will feel that these Tatamis are soft. The tatamis are aligned on an arrangement that forms T joints and not the Cross joints.



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If you are interested in learning how Japanese build and arrange their houses, I recommend that you visit Kyoto. It is a traditional city of Japanese empire. NHK, a state owned TV station, frequently aired programs about that city, one of them is about the alleyway of Kyoto. There thousands of alleyways in Kyoto. They are narrow and bring neighbors closer. We cannot drive car through narrow alleyways. If we want to pass through them, we need to walk or ride bicycles.



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People must respect their neighbors' privacy by not playing music too loud. They have sushi bars and café where neighbors sit together to share stories and experience. I think one day I have to go to Kyoto to see how the style and design of the Japanese wooden house. Besides the wooden house and the alleyway that fascinates me, the public bathroom is also something unique in my own perspective. It is where Japanese take a bath. The public bath is divided into two main rooms, one for men and the other for women.


So, if you plan to go abroad this spring, maybe you can put wooden house and alleyway of Kyoto as your next travel destination. You won't regret if it is your choice. by Charles Roring in Manokwari of West Papua of Indonesia

Wednesday, March 25, 2009

Position of crew room on traditional fishing boat

by Charles Roring in Manokwari of West Papua - Indonesia



17089.JPGNaval architects who design fishing boats frequently have to face many conflicting factors. Fishermen in Europe like to have a wide deck area to enable them to work freely during operation. The superstructure of fishing boat is therefore positioned by ship designers at the forward end of the boat. As a compromise, the rooms for the crews are positioned below the main deck next to the fish hold.


In the contrary, fishermen in Indonesia and Malaysia prefer to have crew rooms and their kitchen on the main deck. As a result the size of the superstructure is bigger and occupies more than sixty percent of the main deck area of the fishing boat. For instance, if the proposed design of LOA is 12 meters with the breadth of 3.6 meters then the deck area of the boat will be around twenty square meters.


A new approach has to be given to new fishing boat designs in Indonesia and Malaysia where working area for the fishermen on the main deck needs to be enlarged. For a traditional fishing boat with four crews, at least two beds for the crews have to be removed from the main deck to the lower deck whereas the kitchen can still be maintained as it has been a traditional custom for the fishermen in Indonesia to have wet kitchen. The new fishing boat design should have at least fifty percent working area for the fisherman to improve their working condition and to allow for more fishing equipment to be installed on the main deck.


In addition, wood which has been the traditional material for boat building in Indonesia can still be used with some introduction of Fiber Reinforced Plastics or FRP materials on the superstructure and joints of the watertight bulkheads that divide main body the fishing boat into engine room, fish hold and crew room.


It is hoped that the new approach on the design of the general arrangement of the fishing boat will improve the productivity of the traditional fishermen in Indonesia. Also read: Super-tanker and the risk of oil spill at sea and Designing Lines Plan with Fastship

Tuesday, March 24, 2009

Super-tanker and the risk of oil spill at sea

23248.JPGSuper tankers have been part of oil trading since 1960s. They are responsible for delivering oil and gas from refineries or producing facilities to other ports around the world. The competition among companies and the increasing demand for oil and gas has been the driving force for the increasing size of the oil carriers.
Frequently these supertankers besides having to cross large oceans such as the Pacific and the Atlantic, they have to pass by narrow yet busy straits and ports. The availability of modern navigational equipment does not guarantee that the supertankers will be free from any risk of collision with other smaller ships or boats. It is the ships' crews who have to safely guard their ships to the unloading ports. Last year, there was a tanker accident in South Korea. Oil spill from this tanker caused huge environmental damage to the coral reef, the sea, the beach as well as the fisherman villages near the area of the accident. Early this year, a cargo vessel loaded with Portland cements, and full with fuel oil in its tanks, collided with a tug boat in Jakarta bay of Indonesia. The vessel sank and spill fuel oil into the sea. Some crews lost their lives. While beach clean up can be done immediately, the destruction in the coral reef environment takes tens or even hundreds of years to recover.
Naval architects, when designing, oil tanker are guided with rules from classification societies, marpol and state regulations. They usually design tankers that have several sections or cargo holds. Collision bulkhead is also drawn at the forward end of the ship. In addition, they also provide double bottom to ensure that the tankers are still safe in case of experiencing grounding. Double bottom, collision bulkhead and double hull are not fully safe in protecting the supertankers during incidents of collision or grounding. When a supertanker experiences severe damage on its collision bulkhead, cofferdam, and double bottom, it will definitely spill oil into the sea.
Another way that we can do to reduce the negative impact of oil spill at sea is to limit the size of supertanker. It is not wise to just follow the request of ship owner by designing 500,000 tons supertanker. Size restriction is needed to ensure that the tankers that we design will not cause massive pollution in busy ports or straights. 
by Charles Roring in Manokwari of West Papua - Indonesia

Monday, March 23, 2009

West Papua needs to develop its agriculture

by Charles Roring in Manokwari of West Papua - Indonesia


One of the visitors of my blog visited me this morning. His name is Jay Hersker. He is from Hawaii. I am personally quite familiar with the word Hawaii. It is where the University of Manoa is located. That campus has department of naval architecture where students from around the world go there to study off-shore engineering supported by ADB and East West Center.


Jay Hersker has been travelling across South East Asia for years. He went to Thailand, Malaysia and now he is in Indonesia. In his opinion, Thailand's development of agriculture is impressive. Thai people can export their surplus of fruit and rice to many countries. In their traditional markets, there are various kinds of fruits sold by vendors.


I and my friend Sylvester Saimar talked with him about sago and varieties of palm trees which are endemic in West Papua. Jay said that he wants to visit Papua University to see their Herbarium. The university also publishes a journal called Beccariana. Although this island has a good agriculture educational institution like Unipa, the agricultural development in West Papua is far from being advanced. More works need to be done to develop the agricultural sector of West Papua.

Thursday, March 12, 2009

Fastship and Delftship for Naval Architects

by Charles Roring in Manokwari of West Papua - Indonesia


delftship-hull.jpgI have just downloaded a ship's hull development software called Delftship. This software is developed for naval architects who are working on ship design offices or students of naval architecture around the world. In my previous article, I said that I use Fastship to develop ship's hull. Fastship is made by Proteus Engineering while Delfship is by Delftship BV in the Netherlands.


Personally, the word Delft is a familiar word for me. It is the town where Delft University of Technology is located. This institution is very famous in my campus when I was a student of Teknik Perkapalan of Universitas Pattimura Ambon. My final assignment was the propeller design of a giant open hatch bulk carrier. I had to read books related to Ship's propulsion. One of the books which I used as my main reference was "Resistance, Propulsion and Steering of Ships." Although it is a very old book, I consider it as a very important book which students of naval architecture should read to widen their knowledge on ship design. The propeller data which is presented in the book is still valid at the moment. I used Troost B4-BP-d Series whereas the resistance is calculated using a method developed by J. Holtrop and G.G. J.Mennen.


Back to the hull development softwares, the availability of the free Delftship has given great opportunities to students of naval architecture around the world to experience an industry standard development of hull form at their own PC or laptops. Software companies which offer such scheme have indirectly promoted their software to young engineers who in the future will become professional ship designers and decision makers in maritime industry in their respective countries.


I will write more about these two softwares in the near future. In Fastship, besides it is a lines-plan software, it can calculate the resistance of ship. How about Delfship? Well, its manual says that it can calculate the GZ curve, stability curve, bending moment and shear force of a ship.

Sunday, March 1, 2009

Houses in Earthquake zone

by Charles Roring in Manokwari of West Papua - Indonesia



wooden-house-minahasa.jpgHouses that are built in active earthquake zone must possess high modulus of elasticity to withstand the ground movement. Usually for traditional houses, people use wood as the framework of their houses. Wood although strong and elastic in nature is combustible. Therefore, for modern building, walls are built from concrete whereas the wood pillars are covered with concrete or other non-combustible materials to prevent them from getting burned during a fire accident.


In tropical region, wood is one of the most favorite home building materials. Besides it is strong enough to support the dead and live loads of the building, wood can stabilize the indoor temperature of the house. Unfortunately, special design concept and wood treatment have to be applied to wooden houses to prevent them from being wholly consumed by the termite.


Earthquakes are mostly tectonic and volcanic. When a volcano erupts, it will release sulphur ash that is corrosive to metal roof. In Indonesia, villagers use earth roof tile or palm leaves as roofing materials. They are resistant to sulphur ash. Palm leaves are called daun atap or atap rumbia. They need to be replaced by new ones every three or five years. Sometimes during the rainy season, the owner of the house has to insert some new palm leaves to mend the leaks. Palm leaves as roofing material is very combustible. It is not recommended to be applied in big cities due to many electrical lines running near the roofs of the houses.


Houses that are constructed in earthquake zone are usually reinforced by the application of steel frames inside the concrete walls to prevent them from bending and fail during an earthquake.


In addition, the height of the walls which are normally 3.5 meters will be reduced to between 2.8 and 3.0 meters to minimize the risk of failure during the earthquake. Reducing the height of the walls will create an impression of hot in tropical houses. As a solution, many homes in quake zones have many windows that are reinforced with wood to support the dead loads of the wall and roof structure.


If I have to choose between wood and steel as reinforcing materials for home, I will choose wood. Also read: Archicad and Revit for House Design