The influences of nano-ZrO2 (NZ), nano-TiO2 (NT), nano-Fe2O3 (NF) and nano-Al2O3 (NA) additions on properties of the fresh and hardened cement paste in comparison with the fine cement paste were experimentally studied. Mini slump and flow cone tests were conducted on fresh cement pastes. Moreover the compressive and tensile strength of hardened cement paste were measured. SEM micrographs and XR...

Developments in IT are rapidly changing the ways in which we communicate research results to provide timely technology transfer to the construction industry. This paper presents a computer database and a Web-based information system that were developed to disseminate the results of a long-term CANMET and U.S. Army Corps of Engineers studies on the durability of marine concrete incorporating sup...

S Jacketing technology using fiber reinforced polymer (FRP) composites is being applied for seismic retrofit and rehabilitation of reinforced concrete (RC) columns designed and constructed under older specifications. In this study, the authors develop an electromagnetic (EM) imaging technology for detecting such damage as voids and debonding between the jacket and the column, which may signific...

Microwave tomographic imaging technology using a bifocusing operator has been developed in order to detect the internal voids/objects inside concrete structures. The imaging system consists of several cylindrical or planar array antennas for transmitting and receiving signals, and a numerical focusing operator is applied to the external signals both in transmitting and in receiving fields. An i...

This paper reports on nine relevant applications of FRP composites in concrete structures in the United States. Strengthening of concrete members with externally bonded FRP laminates or near surface mounted (NSM) bars has received remarkable attention. FRP materials have been used in small projects and some multi-million dollar projects for strengthening parking garages, multi-purpose conventio...