ABSTRACT

In a field measurement programme concrete temperatures were to be recorded for the first week of hardening. The measurement were made in summer 1993 in a period in which day-ni^t temperatures fluctuated considerably. Hydration temperatures were measured by means of NiCr-Ni thermocouples (TC). A thermistor signal served as the reference temperature. Five TC's were placed in the concrete plate symmetrically to the neutral axis. In addition the air temperature was recorded 5 cm above the surface. The TC's were placed in a plasfic tube, which was then filled with PU foam. The completed sensor was fixed to the reinforcement mesh and connected to a data logger. Fig. 1 shows a diagram of the sensor.