Abstract

Concrete is widely used construction material that is known to posses good mechanical properties and is characterized by an overall durable performance. However, the aesthetics of concrete is on the whole non friendly. Hence efforts have been exerted to enhance concrete appearance which can also minimize surface finish costs. Exposed aggregate concrete is a recent technique in which portions of the coarse aggregates are exposed to air by removing small layers of mortar cover. Aggregates exposure techniques include the use of wash-off, water jetting and sandblasting techniques; some of which are accompanied by a surface retarders. However, comparative data on the properties of exposed aggregate concrete in the light of exposure techniques are scarce.

This study is an attempt to improve the understanding of the performance of exposed aggregate concrete and the impact of the exposure technique on the concrete properties. Twenty mixtures were prepared using two commonly used coarse aggregates, dolomite and gravel with 9.5 and 19 mm maximum size. Specimens were prepared using wash-off technique and sandblasting technique accompanied by coasting specimens with two types of surface retarders with a set of conventional mixtures for comparison purposes. Standard fresh and hardened concrete tests were conducted. A simple method was introduced for estimating the exposure size of aggregates based on weight loss. Performance testing was performed; included corrosion assessment of reinforced beams that were subjected to sea water which involved bar weight loss, flexural strength, rebound hammer and ultrasonic assessment. A new method was introduced to evaluate the heat transmission, surface temperature and shadow assessment.

Department

Interdisciplinary Engineering Program

Date of Award

6-1-2005

Online Submission Date

7-24-2005

First Advisor

Mohamed Nagib Abou Zeid

Committee Member 1

Mohamed M. Abdel Razek

Committee Member 2

Medhat A. Haroun

Committee Member 3

Emad H. Imam

Document Type

Thesis

Extent

163 leaves :

Library of Congress Subject Heading 1

Concrete.

Library of Congress Subject Heading 2

Aggregates (Building materials)

Rights

The American University in Cairo grants authors of theses and dissertations a maximum embargo period of two years from the date of submission, upon request. After the embargo elapses, these documents are made available publicly. If you are the author of this thesis or dissertation, and would like to request an exceptional extension of the embargo period, please write to thesisadmin@aucegypt.edu

Call Number

Thesis 2005/71

Location

mgfth;mrs2

Download

Included in

Engineering Commons

Share

COinS