semiconducting carbon nanofibers (cnf) are prepared from three different sources, i.e., acetylene, ethanol, and cotton by the chemical vapor deposition (cvd) process. these fibers are having rich elastic, engineering and conductivity properties. fresh self-compacting concrete (scc) flows into place and around obstructions under its own weight to fill the formwork completely and self-compact, wi...

The uplift of the raft foundation of reinforced concrete buildings, and the consequent partial loss of contact between soil and foundation, is a possible effect of an earthquake. Actually, reinforced concrete buildings with raft foundation are commonly used in nuclear power plants. In this context, some simplified approaches for uplift evaluation have been proposed in the past and are still use...

In this study, first by surveythe parameters affecting the compressive strength, such as water to cement ratio, cementgrade, silica fume to cement percentage, and the various ratios oflight weight aggregate LECA, to total aggregate, Taguchi method is used, to test 9 mix designsobtained the mix design optimization. Since lightweight concrete is brittle like normal concrete, to resolve this probl...

There is a worldwide interest in using fibers of different types in concrete mixtures. In this regard, as the use of PET fibers has gradually increased during the last decade, this study aims to investigate the effects of PET fibers on the mechanical properties of hardened concrete and the workability of fresh concrete. To this end, different contents of PET fibers (PC= %0, %0.5, %1 and %1.5) a...

In the present study, a new method for retrofitting reinforced concrete beam is introduced in which steel-concrete composite jackets containing steel fiber is used. For this purpose, 75% of the peripheral surface of reinforced concrete beams was initially reinforced using steel plates and bolts, and steel fiber reinforced concrete was used between the steel plates and the peripheral surfaces of...