The following topics in the field of seismic analysis and design of mid-rise (5- and 6-storey) wood-frame buildings are included in this paper: Determination of the building period, linear dynamic analysis of wood-frame structures, deflections of stacked multi-storey shearwalls, diaphragm classification, capacity-based design for woodframe...
Using Charles and Ray Eames’s famous 1950s House of Cards slotting toy as both design metaphor and structural precedent provides the starting point for a novel building logic (utilising three existing Swedish timber systems) that allows volumetrically slotted units to stack inside of and support each other. Contemporary computer-aided fabrication techniques based on evolutionary algorithms and CNC manufacturing strategies are used to produce a methodology for designing a kit-of-parts system at the scale of the skyscraper, based on the slotting together of cross-laminated timber (CLT) panels. A catalogue of novel slotting methods is produced, and a number of alternative slotted joint treatments identified that hold promising potential for further development, parametrically design and control volumes, understand the fabrication workflow and constructional sequence on site, and build prototypes of the chosen slotting configurations at scales ranging between 1:50 and 1:1.
The airtightness of building must be measured for the evaluation of building energy performance. To make up the reference airtightness value of wooden houses built in Korea, blower door test was carried out in the 36 houses. And, during the test, the causes of air leakage were inspected simultaneously. The result showed that the average of ACH50((air change per hour at air pressure difference 50Pa) measured from light timber frame houses was 3.5 h-1 and the post-beam construction was 5.1h-1. And, insulation with form of foams was advantageous in ensuring building airtightness than glass fiber batt. And, values below 1.5 h-1 of ACH50, threshold for application of artificial air change equipment, had appeared after 2010s. Also, the values varied according to who managed the building construction field. Although only one measurement of CLT(cross laminated timber) residential building could be obtained in 2016, the result showed good airtightness of building with 0.7 h-1.
New Zealand Society for Earthquake Engineering Conference
April 13-15, 2012, Christchurch, New Zealand
The Nelson Marlborough Institute of Technology Arts and Media building was completed in 2011 and consists of three seismically separate complexes. This research focussed on the Arts building as it showcases the use of coupled post-tensioned timber shear walls. These are part of the innovative Expan system. Full-scale, in-situ dynamic testing of the novel building was combined with finite element modelling and updating to obtain an understanding of the structural dynamic performance within the linear range. Ambient testing was performed at three stages during construction and was combined with forced vibration testing for the final stage. This forms part of a larger instrumentation program developed to investigate the wind and seismic response and long term deformations of the building. A finite element model of the building was formulated and updated using experimental modal characteristics. It was shown that the addition of non-structural elements, such as cladding and the staircase, increased the natural frequency of the first mode and the second mode by 19% and 24%, respectively. The addition of the concrete floor topping as a structural diaphragm significantly increased the natural frequency of the first mode but not the second mode, with an increase of 123% and 18%, respectively. The elastic damping of the NMIT building at low-level vibrations was identified as being between 1.6% and 2.4%
The ambient movement of three modern multi-storey timber buildings has been measured and used to determine modal properties. This information, obtained by a simple, unobtrusive series of tests, can give insights into the structural performance of these forms of building, as well as providing information for the design of future, taller timber buildings for dynamic loads. For two of the buildings, the natural frequency has been related to the lateral stiffness of the structure, and compared with that given by a simple calculation. In future tall timber buildings, a new design criterion is expected to become important: deflection and vibration serviceability under wind load. For multi-storey timber buildings there is currently no empirical basis to estimate damping for calculation of wind-induced vibration, and there is little information for stiffness under wind load. This study therefore presents a method to address those gaps in knowledge.
In this paper, the relations between the load-deformation property of the CLT connections and the seismic performance of the 3 story CLT construction are analytically discussed. The static and the dynamic properties of the CLT connections led each from the static and the dynamic tests were obviously different, however the analytical results based on these properties were agree each with the results of the static and the dynamic tests proving the adequateness of estimated properties. The further study on the dynamic effects of CLT connections is necessary.
Australian Life Cycle Assessment Society conference
The use of timber construction products and their environmental impacts is growing in Europe. This paper examines the LCA approach adopted in the European CEN/TC350 standards, which are expected to improve the comparability and availability of Environmental Product Declarations (EPDs). The embodied energy and carbon (EE and EC) of timber products is discussed quantitatively, with a case study of the Forte building illustrating the significance of End-of-Life (EoL) impacts. The relative importance of timber in the context of all construction materials is analysed using a new LCA tool, Butterfly. The tool calculates EE and EC at each life cycle stage, and results show that timber products are likely to account for the bulk of the EoL impacts for a typical UK domestic building.