低温におけるセメントモルタルの力学的性質

Abstract

With the rapid progress of the chemical industry and the result of coming energy crisis, there is a tendency to increase in usage of a wide range of energy resources and in the quantities. Most typical liquid fuels are liquefied natural gas (LNG). As a result, many diversified hazards associated with LNG are recognized. LNG will be stored in tanks made of, concrete or in underground spaces. But there are many unknown points about behavior of concrete and rocks at low temperatures. Here, the authors studied mechanical characteristics of cement mortar in range of temperature from room temperature to-180°C.Main results obtained are as follows:1) The tensile strength of cement mortar becomes maximum at the temperature of about-150°C and is 2.4 times as large as that at the room temperature.(See Fig. 3)2) The maximum compressive strength is obtained at abovementioned temperature and is 2.2 times as large as that at the room temperature.3) The maximum Young' modulus and Poisson' ratio are obtained at the temperature of about-150°C, and are1.4 and 1.5 times larger than those observed at the room temperature respectively.4) When samples are saturated with water, their maximum tensile and compressive strength are 4.5 times as large as values obtained at the room temperatures. And their Young's moduli become much larger.