Strain gauge load cell for monitoring the strain in prestressed elements or elements subjected to axial strain

Abstract

Strain gauge load cell (16) for monitoring the strain in a prestressed element or element subjected to axial strain, comprising: a hollow cylindrical body (30) for receiving the element whose axial strain is to be measured, and a plurality of strain gauges (12). The body (30) defines an upper surface (1), a lower surface (6) and a side wall (10) which delimits a hole (8). The gauges (12) are arranged on the side wall (10) of the body (30) at an equidistant distance between the upper surface (1) and the lower surface (6). The gauges (12) are connected by means of an electronic assembly (40) in a full Wheatstone bridge. The height of the body (30) is h≥25Øe,∅e being the outer diameter ∅e of the body (30). The outer diameter ∅e fulfils the following: øe≥N/fy2+π4⋅øi2⋅4π wherein ∅i, is the inner diameter of the body (30), N is the axial strain for which the cell (16) has been dimensioned and fy is the elastic limit of the material of the body (30).