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The paper presents the experience of a working group within the RILEM Technical Committee 223-MSC ‘Masonry Strengthening with Composite materials’, aimed at developing a standardized, reliable procedure for characterizing the bonding mechanism of masonry elements strengthened with composite materials under shear actions. Twelve laboratories from European universities and research centers were involved. Two different set-ups were compared, for single-lap and double-lap shear tests (the latter in two versions). Four kinds of fiber fabrics, i.e., glass, carbon, basalt and steel, were applied with epoxy resins (wet lay-up system) to clay brick units, for a total of 280 monotonic tests. The results provided information regarding the response of externally bonded-to-brick composites in terms of observed failure mechanisms, load capacity, effective transfer length, and bond shear stress–slip behavior. The test results of the 12 laboratories constitute a set of statistically representative data which may conveniently be used for setting appropriate design provisions and guidelines

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manufacturing, experimental setup, test execution, and determination of test results are provided.

Development and commercialization of self-healing concrete is hampered due to a lack of standardized test methods. Six inter-laboratory testing programs are being executed by the EU COST action SARCOS, each focusing on test methods for a specific self-healing technique. This paper reports on the comparison of tests for mortar and concrete specimens with polyurethane encapsulated in glass macrocapsules. First, the pre-cracking method was analysed: mortar specimens were cracked in a three-point bending test followed by an active crack width control technique to restrain the crack width up to a predefined value, while the concrete specimens were cracked in a three-point bending setup with a displacement-controlled loading system. Microscopic measurements showed that with the application of the active control technique almost all crack widths were within a narrow predefined range. Conversely, for the concrete specimens the variation on the crack width was higher. After pre-cracking, the self-healing effect was characterized via durability tests: the mortar specimens were tested in a water permeability test and the spread of the healing agent on the crack surfaces was determined, while the concrete specimens were subjected to two capillary water absorption tests, executed with a different type of waterproofing applied on the zone around the crack. The quality of the waterproofing was found to be important, as different results were obtained in each absorption test. For the permeability test, 4 out of 6 labs obtained a comparable flow rate for the reference specimens, yet all 6 labs obtained comparable sealing efficiencies, highlighting the potential for further standardization.