Strain and deformation measurement on civil engineering sample - involves use of socket joints ensuring rotational alignment with sample surface

摘要

Strain and deformation measurements are made on civil engineering samples by use of socket joints which ensure that centre of rotation is aligned to upper and lower surfaces of the sample. A sample (11) is mounted in an upper head (12) with socket joint (13) and is retained in lower head (5) by lower socket (8) acting against spring (9) loaded screw (7) which also eliminates any play. The upper socket is attached to shaft (18) and socket (17) by screw (16) in the socket carrier (15). The shaft transmits force to the sample.