This paper presents the results of a series of self-healing experiments conducted on reinforced mortar beams containing adhesive-filled glass reservoirs. An overview of the findings of the preliminary investigation stage of experiments is given in addition to the results of a parametric study which investigates the effect of the level of reinforcement and loading rate on the amount of self-healing. Results show that both primary and secondary healing occurs during the first and second loading cycles respectively. Qualitative results also show clear evidence of the occurrence of crack-healing following the first loading cycle and new crack formation during the second loading cycle. The long-term motivation for this work is to provide data suitable for the development of a numerical material model for the autonomic healing process in cementitious materials.

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An investigation of the transient thermomechanical behavior of poly(ethylene terephthalate) (PET) is presented with respect to a new composite material system in which shrinkable PET tendons are incorporated into a cementitious matrix to provide a crack-closure mechanism. A series of parametric studies of the effects of the geometry, temperature, and soak time on the mechanical properties of the polymer are presented. In particular, this article focuses on the shrinkage behavior and the development of stresses under restrained shrinkage conditions. A one-dimensional numerical model, which is essentially a modification of Zener's standard linear solid model, is presented with the aim of simulating aspects of behavior of particular relevance to tendons within the composite material system. The model comprises a temperature-dependent dashpot and spring in parallel with a spring and thermal expansion element. The temperature-dependent functions are calibrated with the obtained data, and a final validation example that shows good accuracy in comparison with experimental data not used for the calibration is presented.

Historically construction materials have been designed to meet a fixed specification and material degradation has been viewed as inevitable and mitigated for through expensive maintenance regimes. Material scientists have recently begun developing materials which have the ability to adapt and respond to their environment, drawing on their knowledge and familiarity of biological systems. This fundamental change in material design philosophy has resulted in the creation of a whole host of ‘smart’ materials, including self-healing materials. The development of self-healing materials is reviewed in this paper, together with definitions of common terminology. A brief summary of the construction industry is given, together with a synopsis of the main issues of durability relating specifically to cementitious materials. Specific focus is then given to both autogenic (natural) and autonomic (manufactured) healing processes within cementitious materials. The paper concludes with a summary of self-healing materials, an overview of their potential use within the construction sector, and recommendations to this sector for future uptake of these new and innovative materials.

This paper presents an experimental study on autogenous healing in a recently