An Experimental Study on Age Effect under Saturated Condition on Thermal Properties of Mass Concrete

Abstract

This paper presents experimental study, investigating the effect of age on thermal properties of mass concrete. Six design mixes were analysed for thermal properties i.e. Thermal Conductivity, Diffusivity and Specific Heat using Hot Disk TPS 1500 system at the age of 7, 28, 56 and 90 days and tests were performed on samples of the same volume (150 x 150 x 150 mm) under saturated curing conditions and at room temperature. It is expected that the thermal properties of the concrete depends on its age and the applied curing conditions. The thermal properties of concrete can progress with the progression of hydration. While the hydration process is highly dependent on the curing condition that is applied.Results also showincrease in thermal conductivity and diffusivity of concrete with age under saturated condition whereas specific heat decreases

Introduction

The thermal properties of concrete—thermal conductivity, thermal diffusivity, and specific heat—are crucial for assessing concrete’s performance over time. Concrete’s high thermal mass allows it to absorb and store heat, while its moderate thermal conductivity affects heat transfer, helping moderate temperature fluctuations in structures. These thermal properties vary depending on factors such as cement type and content, aggregate, water, admixtures, age, saturation, and temperature.

This study experimentally measured thermal properties of mass concrete under saturated conditions at different ages (7, 28, 56, and 90 days) using several concrete mix designs with different cement types (PPC and PSC) and aggregate proportions. Specimens were prepared, cured, and tested with the Hot Disk TPS 1500 device, which uses the Transient Plane Source technique to determine thermal conductivity, diffusivity, and specific heat by placing a sensor between two halves of the concrete samples and measuring heat flow responses.

Results show that thermal conductivity and diffusivity increase with age under saturated conditions, while specific heat decreases. The study highlights how age and mix composition influence concrete’s thermal behavior, which is important for designing durable and energy-efficient concrete structures.

Conclusion

This investigation aimed to evaluate the influence of age under saturated conditions on the thermal properties of concrete, focusing on Thermal Conductivity, Thermal Diffusivity, and Specific Heat. The results derived from the extensive testing yield the following conclusions: 1) The Thermal Conductivity of concrete is affected by both age and moisture, showing an upward trend with age when assessed under saturated conditions. 2) There is a notable increase in the Thermal Diffusivity of concrete as age advances when tested under saturated conditions. 3) However, the Specific Heat of concrete experiences a decline with age under saturated conditions.

References

[1] ACI committee, 116R-05: Cement and Concrete Terminology [2] ACI committee, ACI 207.1R-05 : Guide To Mass Concrete [3] ACI committee, ACI 207.2R-07 : Report On Thermal And Volume Change Effects On Cracking Of Mass Concrete [4] ACI committee, ACI 224R-01 : Control Of Cracking In Concrete Structures [5] ACI committee, ACI 301-16 : Specifications For Structural Concrete [6] ACI committee, ACI 305R-10 : Guide To Hot Weather Concreting [7] Indian Standard, IS 14591: 1999 (Reaffirmed 2015) Temperature Control for Mass Concrete for Dams – Guidelines [8] Properties of Concrete, A M Neville [9] Thermal properties of reinforced structural mass concrete, US Department of the Interior Bureau of Reclamation [10] Effect of heat generation from cement hydration on mass concrete placement, Soo Geun Kim, Iowa State University

Copyright

Copyright © 2025 Lalit Kumar Solanki, Ravi Agarwal, B. K. Munzni. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.