Title

Effects of Saturated Lightweight Sand Content on Key Characteristics of Ultra-High-Performance Concrete

Abstract

In this study, 0 to 75% volume of river sand was replaced by an equivalent amount of pre-saturated lightweight sand (LWS) to enhance mechanical properties and reduce autogenous shrinkage of ultra-high-performance concrete (UHPC). The use of LWS is demonstrated to effectively decelerate and reduce the drop in internal relative humidity and autogenous shrinkage of UHPC. Isothermal calorimetry and thermal gravimetry results showed that the use of LWS promoted cement hydration degree after 28 d of hydration. Mercury intrusion porosimetry and scanning electron microscope analyses revealed that the porosity was decreased and interface properties between sand and cement matrix is enhanced by use of LWS up to 25%. The optimum replacement ratio of LWS to river sand was found to be 25%, which resulted in the highest compressive strength (168 MPa at 91 d), flexural strength (24 MPa at 28 d), and autogenous shrinkage limited to 365 μm/m at 28 d.

Department(s)

Civil, Architectural and Environmental Engineering

Comments

This study was funded by the Energy Consortium Research Center of Missouri S & T [grant number SMR-1406-09] and the RE-CAST University Transportation Center at Missouri University of S & T [grant number DTRT13-G-UTC45].

Keywords and Phrases

Cements; Compressive strength; Concretes; Hydration; Mechanical properties; Mercury (metal); Microstructure; Sand; Scanning electron microscopy; Shrinkage; Autogenous shrinkage; Interface property; Internal curing; Internal relative humidity; Isothermal calorimetry; Key characteristics; Mercury intrusion porosimetry; Ultra high performance concretes; High performance concrete; Lightweight sand; Ultra-high-performance concrete

International Standard Serial Number (ISSN)

0008-8846

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2017 Elsevier, All rights reserved.

Share

 
COinS