Craft, Detail & Quality

<p>Over the past decade and even currently within New Zealand there have been quality issues within timber construction. My research proposes to address what these quality issues are both functionally, and aesthetically and how we can create a dialogue between craft, detail and quality. In residential architecture in New Zealand, the most common practice is timber stud framing or otherwise known as traditional platform framing. This construction type results in little variety throughout NZ as the vast majority is dominated by NZS:3604. This common platform framing can also create architecture that barely resembles the timber material. This research creates a framework to what will be a possible solution in exposing the details of timber joints, which in turn may prevent quality issues along with creating a crafted timber design. As a starting point for this research, it seemed appropriate to draw on traditional Japanese, European and Pacific construction techniques. These cultures have mastered the art of craft, and we in New Zealand could learn from this and reflect in contemporary practices in NZ. This could in turn create a solution which highlights the quality issues in construction of New Zealand residential architecture. Typically, in New Zealand platform framing construction, timber joint details are concealed. These concealed details are more prone to failure and so by exposing these, it can lead to improving quality of construction. Quality is, however, an elusive concept and this will become clear through an analysis of interviews with numerous builders, project managers, architects and of course the everyday user. These interviews define what they believe is the most common area of defect, and where quality can be improved. This research will therefore look at what system can be designed between the connections of architectural elements to focus on exposed refined details and joints. As these connection details are explored the definition of “craft” will become more defined, where it currently begins as examples of exposed, visible and readable detail. Taking place in a rural New Zealand environment in Raglan Waikato, the portfolio proposes a boutique hotel, with a scheme that demonstrates this newly proposed construction system as an alternative to platform framing. The role of the hotel design is merely a vehicle to apply and test the research. There are many implications that may be a factor in the conclusion of this research proposal, for example CLT timber accessibility and costs. However further outcomes will result in celebration and awareness of detailing which leads to improving quality of New Zealand timber architecture. This research explores turning traditional methods of construction into contemporary architecture using the technologies and material practices of today.</p>

Craft, Detail & Quality

<p>Over the past decade and even currently within New Zealand there have been quality issues within timber construction. My research proposes to address what these quality issues are both functionally, and aesthetically and how we can create a dialogue between craft, detail and quality. In residential architecture in New Zealand, the most common practice is timber stud framing or otherwise known as traditional platform framing. This construction type results in little variety throughout NZ as the vast majority is dominated by NZS:3604. This common platform framing can also create architecture that barely resembles the timber material. This research creates a framework to what will be a possible solution in exposing the details of timber joints, which in turn may prevent quality issues along with creating a crafted timber design. As a starting point for this research, it seemed appropriate to draw on traditional Japanese, European and Pacific construction techniques. These cultures have mastered the art of craft, and we in New Zealand could learn from this and reflect in contemporary practices in NZ. This could in turn create a solution which highlights the quality issues in construction of New Zealand residential architecture. Typically, in New Zealand platform framing construction, timber joint details are concealed. These concealed details are more prone to failure and so by exposing these, it can lead to improving quality of construction. Quality is, however, an elusive concept and this will become clear through an analysis of interviews with numerous builders, project managers, architects and of course the everyday user. These interviews define what they believe is the most common area of defect, and where quality can be improved. This research will therefore look at what system can be designed between the connections of architectural elements to focus on exposed refined details and joints. As these connection details are explored the definition of “craft” will become more defined, where it currently begins as examples of exposed, visible and readable detail. Taking place in a rural New Zealand environment in Raglan Waikato, the portfolio proposes a boutique hotel, with a scheme that demonstrates this newly proposed construction system as an alternative to platform framing. The role of the hotel design is merely a vehicle to apply and test the research. There are many implications that may be a factor in the conclusion of this research proposal, for example CLT timber accessibility and costs. However further outcomes will result in celebration and awareness of detailing which leads to improving quality of New Zealand timber architecture. This research explores turning traditional methods of construction into contemporary architecture using the technologies and material practices of today.</p>

Optimal trajectory planning of complicated robotic timber joints based on particle swarm optimization and an adaptive genetic algorithm

In this paper, a methodology for path distance and time synthetic optimal trajectory planning is described in order to improve the work efficiency of a robotic chainsaw when dealing with cutting complex timber joints. To demonstrate this approach one specific complicated timber joint is used as an example. The trajectory is interpolated in the joint space by using a quantic polynomial function which enables the trajectory to be constrained in the kinematic limits of velocity, acceleration, and jerk. The particle swarm optimization (PSO) is applied to optimize the path of all cutting surfaces of the timber joint in operating space to achieve the shortest path. Based on the optimal path, an adaptive genetic algorithm (AGA) is used to optimize the time interval of interpolation points of every joint to realize the time-optimal trajectory. The results of the simulation show that the PSO method shortens the distance of the trajectory and that the AGA algorithm reduces time intervals and helps to obtain smooth trajectories, validating the effectiveness and practicability of the two proposed methodology on path and time optimization for 6-DOF robots when used in cutting tasks.

Resisting Timber Joint Performance of Karo Wooden Building

Batak Karo is one of the ethnic group that exists in North Sumatra. Wooden house of Batak Karo called with Siwaluh Jabu. This wooden house has a structure system of pillars on top of stone foundations. This type of foundation is able to improve the performance of the overall structure due to lateral style caused by the earthquake. This research was conducted to know the behaviour of the structure of a wooden Batak Karo home especially the restoration of wooden style joints by comparing the results of a laboratory test, numerical analysis and analysis with SAP2000. Experimental testing in the lab do the test objects as much as 3 pieces. Testing by giving a cyclic load with a capacity of 10 tons in each of the test object to damaged object. Then conduct an evaluation the behavior of the structure consist of failure modes and moment-rotational angle relationship. After the experimental test was completed, the analysis continued with validate test results with laboratory of numerical analysis. Then conducted an analysis of the power structure by using SAP2000 program to know the power of elements against the maximum tension. The analysis conducted on the overall structure of the system and the structure of mast above the foundation stone. The program was conducted with input data: the work load, etc. As the output from these programs is the element force, etc. The final results of this program are the weaknesses and advantages of structural system observed from wooden Batak Karo.

Beam-Column Timber Joint Connection Behavior Due to Nail and Modified-Washer Reinforcement Tests

Timber connection capacity, in case of beam-column joint connection provides significant impact on the wooden building structures. Strength and stiffness of timber connections using reinforcement technique of wooden building structures have not been studied intensively. This paper studies the use of nails and modified-washer to improve wood connection’s performance. The experimental tests were conducted in the laboratory by comparing the partial connection between test specimen timber without reinforcement (standard type) and the reinforcement (PRP type). The testing was conducted based on partial connection beam-column joint test using Universal Testing Machine’s with a modified holder. Wood studied includes Meranti (Shorea spp.) and Mersawa (Anisoptera spp.). PRP type connection was using nails and modified-washer strengthening, and standard type connection was using a classic washer. Parameters studied were strength and stiffness of the connection, reviewed both: proportional limit load and ultimate limit load conditions. Result obtained from this research indicates that the use of nails and modified-washer make a positive contribution to improving the performance of the beam- column timber joint connections, in terms of strength capacity (both of proportional limit and ultimate limit loads) and stiffness capacity (displacement ductility ratio). Meranti beam-column timber joint is more brittle than Mersawa beam column timber joint, it has an impact on the results. PRP-type of Mersawa timber connection produces a higher ductility than the standard type, while the PRP-type of Meranti timber connection produces a similar ductility to the standard type.

DOUBLE SHEAR TEST BEHAVIOUR OF BALAU SPECIES FOR DIFFERENT END DISTANCE

Timber connection is the most important part in timber structural building. In design, it depends on parameter criteria such as bolt diameter, bolt spacing, edge and end distance. End distance is one of design criteria that will influence mechanical timber joint such in single and double shear. This study focuses for a single fastener joint loaded in double shear with 12mm and 16mm bolt diameters having 30mm and 40mm end distance respectively. Double shear test was conducted on Balau timber species and the finding also focuses on the pattern failure modes with reference to European Yield Model (EYM) theory according to National Design Specification (NDS) 2005. It shows that the joint ability to withstand load decreased when the bolt diameter and end distance smaller and conversely with larger bolt diameter. The failure behavior for 12mm diameter tends to fail into category IIIs which described two plastic hinges formed with crushing of wood fibres in the side members. While, 16mm diameter bolt tends to fail under categories of mode Is which dowel bearing failure or crushing of the side members. Eventually, 12mm bolt diameter produces lower shear strength compared to 16mm bolt diameter.