fiber reinforced concrete (frc) has been widely used due to its advantages over plain concrete such as high energy absorption, post cracking behaviour, flexural and impact strength and arresting shrinkage cracks. but there is a weak zone between fibers and paste in fiber reinforced concretes and this weak zone is full of porosity, especially in hybrid fiber reinforced concretes. so it is necess...

Provisional restorations represent an important phase during the rehabilitation process, knowledge of the mechanical properties of the available materials allows us to predict their clinical performance. At present, there is no systematic review, which supports the clinicians' criteria, in the selection of a specific material over another for a particular clinical situation. The purpose of this...

The influence of short-term water absorption on the mechanical properties of halloysite nanotubes-multi layer graphene reinforced polyester hybrid nanocomposites has been investigated. The addition of nano-fillers significantly increased the flexural strength, tensile strength, and impact strength in dry and wet conditions. After short-term water exposure, the maximum microhardness, tensile, fl...

The mechanical properties of high-strength ductile concrete (HSDC) have been investigated using Metakaolin (MK) as the cement replacing material and PVA fibers. Total twenty-seven (27) mixes of concrete have been examined with varying content of MK and PVA fibers. It has been found that the coarser type PVA fibers provide strengths competitive to control or higher than control. Concrete with co...

ZrB₂-based nanocomposites with and without carbon nanotubes (CNTs) as reinforcement were prepared at 1600 °C by spark plasma sintering. The effects of CNTs on the microstructure and mechanical properties of nano-ZrB₂ matrix composites were studied. The results indicated that adding CNTs can inhibit the abnormal grain growth of ZrB₂ grains and improve the fracture toughness of the composites. Th...

Polymer blends composites were prepared according to the formula [84%LLDPE:15%((100-X)%PP:X%PVP):1%B.P] with weight ratios selected for X values (0,4,8,12,16 %), as strips by double screw extruder and use press process the strips to prepare the samples according ASTM specification, the mechanical properties were studied for all theprepared samples which are (tensile, flexural, compression, impa...

Resin composites currently available are not suitable for use as large stress-bearing posterior restorations involving cusps due to their tendencies toward excessive fracture and wear. The glass fillers in composites provide only limited reinforcement because of the brittleness and low strength of glass. The aim of the present study was to reinforce dental resins with ceramic single-crystalline...

The most common bone cement material used clinically today for orthopedic surgery is poly(methyl methacrylate) (PMMA). Conventional PMMA bone cement has several mechanical, thermal, and biological disadvantages. To overcome these problems, researchers have investigated combinations of PMMA bone cement and several bioactive particles (micrometers to nanometers in size), such as magnesium oxide, ...

Polymer concrete (PC) is a composite material prepared by resin and aggregates. Advantages of polymer concretes include rapid curing at ambient temperatures, high flexural and compressive strengths, excellent chemical resistance and low permeability. In this research, a comparative study was performed on degradation of polyester resin concrete in different chemical solutions. Polymer concrete s...

EFFECTS OF RUBBER ADDITIVES ON PROPERTIES OF ASPHALTIC MATERIALS by JOHN ALBERT ALEXANDER Submitted to the Department of Civil Engineering on August 17, 1968, in partial fulfillment of the requirements for the degree of Master of Science in Civil Engineering. This study investigated the modification of asphalt with various rubbers and the effect of this modification on the values of fracture to...