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Many materials and certain material applications require detailed preconditioning and specific thermal test schedules to be followed to obtain a correct evaluation of thermal expansion. Since a general test method cannot cover all specific requirements, details of this nature should be contained in the relevant material specification. The standard testing method to measure the linear thermal expansion is based on contact methods (ASTM E228-95, Standard Test Method for Linear Thermal Expansion of Solid Materials with a Vitreous Silica Dilatometer). The Thermal Mechanical Analysis (TMA), measures the change of length of the specimen during heating by using a vitreous silica push-rod or tube dilatometer. A big disadvantage of this method is the restricted size of the specimens. When using the TMA method on fibre reinforced composites; the small specimens required (maximum 5 x 5 mm cross section) are not representative for the behaviour of the composite, so the method is not applicable. In this paper the coefficient of linear thermal expansion will be determined by using a contact (TMA) and a non contact method based on digital image correlation (DIC). This full field optical non contact method measures the in-plane displacements of the object surface [1]. By using software the data of the DIC measurement can be converted to strain values which can be used to calculate the coefficient of thermal expansion. The aim of this study is to use both testing methods on different material in order to calibrate and verify the usability of the method to determine the linear thermal expansion coefficient

Strengthening and repairing existing reinforced concrete structures is often more economical and sustainable than rebuilding them. Today the most commonly used technique here fore is the application of externally bonded Carbon Fibre Reinforced Polymers (CFRP). Still, they do not answer the need for a temperature resistant, fire safe and economical solution. High performance glass fibre Textile Reinforced Cements (TRC) can offer an answer to these drawbacks. A validation of this TRC technique against the existing and established one of CFRP is still needed. The Digital Image Correlation (DIC) and Acoustic Emission (AE) measuring techniques are applied to monitor the bending, cracking and failure behaviour of a reference beam, a similar beam with additional external CFRP reinforcement and a similar precracked and non-precracked beam externally reinforced with TRC. Four-point bending tests indicate the successful complementary use of DIC and AE and prove that TRC as an external reinforcement for concrete beams actually works.

The use of a recently developed inorganic phosphate cement with grain sizes less than 100 micrometer in combination with an adapted manufacturing process creates the possibility to obtain cement composites with a never been seen fiber volume ratio (Vf) of up to 25-30%, a factor 2 to 10 times higher than conventional cement composites. The forthcoming gain in tensile strength enables the material to be used in high performance building applications such as sandwich panels, structural claddings and concrete repair. This paper presents a concept for a lightweight stay-in-place cement composite formwork taking advantage of this new promising material. Full scale tests analyzing the structural behavior indicate the opportunities of this innovative forming technique. Results also show an improved mechanical behavior of the composite (concrete-formwork) beam as the micro cracking phenomenon of concrete in tension is better controlled and crack propagation is delayed compared to a traditional steel reinforced concrete beam.