Correspondence

In contrast to driving bearing piles for which the direct resistance below the point often becomes greater than the frictional value that the sides can afford, sheet steel piles encounter the greater proportion of their resistance through friction between the ground and their side surface which is very considerable compared with the sectional area of the solid steel pile which can, however, transmit a very high driving force without becoming deformed. A. Hiley

THEORETICAL DISCUSSION. In 1833 Clapeyron stated his law of general work: “For any frame of constant temperature and acted on by loads which are gradually applied, the actual work produced during deformation is independent of the manner in which these loads are created and is always half as great as ths work otherwise produced by forces retaining their full end values during the entire act of deformation.” H.W. Coultas

This month's letters cover legislation for design checks, embodied carbon of modular construction approaches, and assessment of masonry buildings for earthquake resilience in New Zealand.