الفهرس | Only 14 pages are availabe for public view |
Abstract Radical new advancements are occurring in the cement sciences resulting in a new generation of high performance self-compacting concrete (HPSCC). HPSCC is characterized by high compressive strength and excellent durability properties resulting in lighter structures and longer life. With advances in concrete technology, HPSCC has become a new focus for researchers and the concrete industry. Each new generation of this concrete is stronger than the previous, and the applications of this super strong blend are endless. HPSCC is a modern creation that is changing the way we look at construction; it is designed primarily for use in large construction projects (pouring rates of about 1O,000m3/day) such as those projects began to have presence in our middle east. Since fire represents one of the most severe environmental conditions to which structures may be subjected in their life time. Furthermore, there is still a lack in the understanding the performance of HPSCC structures in real fires due to the severe lack of data available in this field. Based on this fact this research aims to study the effect of high elevated temperature and direct fire on the performance of HPSCC. This study is conducted on three parts. The first part of this study is carried out to study the effect of high temperatures on the mechanical strengths of HPSCC. Four concrete mixes were investigated. The first mix represented HPSCC without fibers. The second mix represented HPSCC including steel fibers. The third mix represented HPSCC including steel and micro-polypropylene fibers. The fourth mix represented HPSCC including steel, polypropylene and polyolefin fibers. The average compressive strength of the investigated concrete mix was 130 MPa. Compressive, tensile and flexural strengths were measured at room temperature (RT) and after exposure to high temperatures of 2000C, 4000C, 6000C and 7500C for 2 hours. The residual unstressed test method is followed. Microscopic examination using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM). |