Behavior of cements and related materials under hydrostatic pressures up to 10,000 atmospheres

Abstract

Compression studies were made o n harde ned cement pastes at 21 0 C a nd a t press ures as high as 10,000 atmospheres. The effects of composit io n, age, m oisture co nte nt, and water-ceme nt ra tio were s tudied. Compressibility of dried portla nd cement p astes appeared to proceed t hrough a maximum wi t h increased cure, the existence or location of t he maximum being d epende nt on t he water-ceme nt ratio. Compression of both portland a nd aluminous ceme nts increased wi th increasing e vaporable water co nte nt. Portla nd ceme nts with evaporable water conte nts in t he range 17. 5 to 32.4 perce n t exhibited a t ransit io n between 2,000 and 3,000 atmospheres. N o similar effect occm ed in a luminous ceme nt. Experiments indicated t hat t he t rans it io n was a ttributable to h ydrated lime formed in t he po rt la nd cem ent. Average co mpressibilities of dri ed paste were 3.1 X 10-6 a nd 2.2 X 10-6 atm-I bet wee n 1 and 5, 000 a t mospheres and betwee n 5, 000 a nd 10,000 atmospheres, res pectively. Co mpress io n tudies were a lso mad e wi t h wet s ilica gel, h ydrated t ricalcillm s ili cate, a nd dr y a nd wet calcium h ydrox id e.