Cross-laminated Timber Construction Research Articles

Timber Engineering Notebook No. 12: Cross-laminated timber construction – manufacture, detailing and erection

This article provides further information on the manufacture, detailing and erection of CLT constructions.

Timber Engineering Notebook No. 11: Cross-laminated timber construction – an introduction

This article provides a more detailed introduction to the applications and use of CLT as a structural timber product, including structural benefits and benefits to the construction process.

Evaluation of bending tests on composite glulam–CLT beams connected with double-sided punched metal plates and inclined screws

Composite beam elements made of glulam beams and cross laminated timber (CLT) panels, and connected with a new shear connection system were tested under four point bending. The beams tested represent a section of a cassette floor element to be used in a multi-storey CLT construction system. The shear connection is primarily made of double-sided punched metal plate fasteners, connecting the CLT and glulam members to form a T-cross-section. Due to the uncertainty about the capacity of the double-sided nail plates to resist possible separation forces between the timber members, the shear connection may be secured with screws. Bending tests were performed with three shear connection configurations: double-sided punched metal plate fasteners only, inclined screws only, and double-sided punched metal plate fasteners combined with inclined screws. An additional test with a screw-glued connection was made for comparison. The results show that a shear connection with double-sided nail plates can be designed to provide a sufficiently high level of composite action and load-carrying capacity and represents an alternative shear connection system for glulam–CLT composite floors.

DEVELOPING A PREFABRICATED LOW-CARBON CONSTRUCTION SYSTEM USING CROSS-LAMINATED TIMBER (CLT) PANELS FOR MULTISTOREY INNER-CITY INFILL HOUSING IN AUSTRALIA

Prefabricated engineered solid wood panel construction systems can sequester and store CO2. Modular cross-laminated timber (CLT, also called cross-lam) panels form the basis of low-carbon, engineered construction systems using solid wood panels that can be used to build residential infill developments of 10 storeys or higher. Multi-apartment buildings of 4 to 10 storeys constructed entirely in timber, such as recently in Europe, are innovative, but their social and cultural acceptance in Australia and North America is at this stage still uncertain. Commercial utilisation is only possible if there is a demand and user acceptance.This paper explores the opportunities offered by an innovative low carbon construction system using cross-laminated timber (CLT) panels to improve the design and delivery of urban infill housing. CLT construction has been developed around 1996 in Austria: layers of timber boards are glued crosswise in different directions to increase loadbearing capacity. The paper describes a multi-disciplinary research project into cross-laminated timber panels which aims to transform the Australian construction and development industry, involving a range of key partners. This project will introduce cross-laminated timber panels as a way to build with a lightweight prefabricated low-carbon construction system that is advantageous for urban infill and residential buildings in the range of 4 to 8 stories height. The challenges, research questions and advantages of this new engineered timber system are explained, and a detailed research methodology for further research is presented.

On the uncertainty of building acoustic measurements – Case study of a cross-laminated timber construction

If variations and uncertainty in building acoustic measurements can be controlled, construction costs can potentially be reduced since the building will not have to be acoustically over-designed. Field measurements of impact and airborne sound insulation were carried out for an industrially prefabricated cross-laminated timber (CLT) system of plate elements. The results from 18 rooms, forming three groups with respect to size, were compared to a similar study dealing with a prefabricated Volume Based Building (VBB) system. Large variations were found at frequencies below 100Hz which is crucial for the low frequency adaptation terms connected to the weighted sound insulation indices. The measurement uncertainty was investigated by analysing the repeatability, measurement direction and the time dependence of the sound source. The variations due to the measurement procedure were found to be small compared to the total variations. It was also indicated that the variations in sound insulation are smaller with a prefabricated system compared to on-site production, since less work is required at the building site.

Stadthaus, London: raising the bar for timber buildings

The nine-storey Stadthaus building in Murray Grove, London is the world’s tallest timber residential building. It is also the first building of this height to have load-bearing walls and floor slabs as well as stair and lift cores constructed entirely from cross-laminated wooden panels. While cross-laminated timber construction has been around since the 1970s, several problems limited its use above six storeys. However, the advantage of low or negative embodied carbon dioxide, clean and safe processes and rapid assembly have prompted a range of solutions enabling taller structures. This paper describes the design and construction of the project, the practical and legislative concerns addressed and the lessons learned.