background: in megavoltage radiotherapy rooms, ordinary concrete is usually used due to its low construction costs, although higher density concrete are sometimes used, as well. the use of high-density concrete decreases the required thickness of the concrete barrier hence, its disadvantage is its high cost. in a nuclear reactor, neutron radiation is the most difficult to shield. a method for p...

in this paper, the effect of polypropylene fibers added to concrete on strength and thermal resistance of high strength concrete has been investigated. therefore, five tests have been carried out to reach this goal which it includes; effect of weight percent of polypropylene fibers on mechanical properties of concrete, effect of fiber’s length on the strength of high strength concrete, effect o...

The purpose of the work reported in this paper is to assess performance recycled ultra-high durability concrete (R-UHDC), produced using different fractions aggregate obtained from crushed (UHDC), as a substitute for natural aggregate. Four (R-UHDC) mixes were designed and manufactured with reference mix based on three replaced UHDC according two percentage replacement values (50 100%). effect ...