Soil Instruments 1030, Руководство пользователя

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User Manual
13
Section 8 :
Temperature Effects
The curing of concrete can generate large temperature changes. It is therefore best practice to record
temperature when you record strain readings. You can then use the temperature data as well as strain data to
analyse the behaviour of the structure.
Temperature induced expansions and contractions can cause real changes in stress in the concrete if the
concrete is restrained, these are superimposed on other load related stresses.
Differences between the coefficient of expansions of the concrete and that of the steel in the strain gauge
itself give rise to an apparent change in strain in the concrete. This apparent change can be corrected for
using the equation below.


corrected =
) ( ) (
0 1
Temp Temp x TC TC
c g
   

Where:


is the change in strain,
c
TC
is the thermal coefficient of concrete in

/°C
g
TC
is the thermal coefficient of the gauge:12.2

/°C
1
Temp
is the current temperature
0
Temp
is the initial temperature