Responsible partners: SerQ (Portugal) and Cesefor (Spain)

Description: The use of timber within the construction sector has several advantages, being the most mentioned: i) renewable source; ii) high strength/weight ratio; iii) easy to handle; iv) pre-fabrication of Engineered wood products; among others. Timber can also be used in combination with other materials like concrete which has been used for mid- and high-rise buildings. However, the new processes of timber construction with mass timber elements, namely Cross Laminated Timber (CLT), are mainly assembled with steel connectors.

Using structural composite elements, namely timber-concrete composite elements for floors has been considered for rehabilitation purposes with evident benefits. The increase in floor stiffness, as well as the higher load carrying capacity are the most relevant.

The purpose of Experiment nº3 is to assess the mechanical performance of CLT-concrete connections behaviour with local softwood species (maritime pine, radiata pine and scots pine). The experimental campaign was established based on:

  • Theoretical design based on codes (e.g. CEN/TS 19103:2021);
  • Production of CLT elements at laboratory facilities;
  • Concrete pouring on CLT elements;
  • Double shear push-out tests.

Different configurations of notch connections were established based on the codes and innovative solutions, considering as variables: i) the depth of the notch; ii) the length of the notch; iii) notch configuration; iv) species used; v) concrete (in-situ or pre-fabricated).

The tests will follow EN 26891 protocol for loading and two main results will be obtained: i) load carrying capacity; ii) slip modulus. The failure mode will be recorded and the results will be crucial for the design of CLT-concrete beam elements (Experiment nº4).