A comparison of concrete containing recycled concrete coarse aggregates and natural coarse aggregates subjected to high strain, low cycle compressive fatigue is presented. Using a strain based feedback control loop, concrete cylinders are compressed at 15µε/s to a specified strain then unloaded to zero stress for 10 cycles. After cycling, all samples are loaded to a strain of 0.008. Direct conc...

-This paper presents the compressive strength of PET fibre reinforced recycles aggregate concrete. The Natural Aggregate (NC) was replaced by recycle aggregate (RA) in the proportion of 25, 50, 75 and 100%. PET fibres were added to the Recycle Aggregate Concrete (RAC) by 1 and 2% volume. Total 45 cubes were cast and tested. The results showed that as the % of RA and volume fraction of PET fibre...

In this work, it is described an experimental analysis of specimens of recycled concrete (RC) with replacement of natural aggregate with recycled aggregate originating from concrete (RCA). An experimental analysis to obtain the shrinkage and creep properties (basic and by drying) of RC was carried out. The replacement fraction of natural aggregate with RCA were 0%, 15%, 30%, 60% and 100% and th...

Aggregate edge detection is the basis of creating concrete mesoscale model, which is applied to analyze concrete mesoscale characteristics. A concrete digital image edge detection method using DIS operator is presented in this paper. Mean filter, multi-scale filter, and Gaussian filter are compared on the effect of concrete image noise reduction. Based on the result, Gaussian filter is the most...

A new patented lightweight aggregates is tested. This type is given the name Flashag. The only solid raw material used to manufacture these aggregates is fly ash. The aggregates are sintered but not pelletized and the process is easy and inexpensive. This paper describes these patented aggregates and compares them with other lightweight and normal-weight aggregates that are used for concrete. T...

In order to assess the bond behavior of deformed steel rebars in recycled-aggregate concrete (RAC) incorporating both fine and coarse recycled aggregate, pull-out tests were carried out in this study on 16-mm diameter deformed steel rebars embedded concentrically in RAC. The concrete was designed using equivalently mixed proportions of both recycled coarse aggregate and recycled fine aggregate....

A numerical method from the mesoscopic point of view is proposed to describe the fracture process of concrete. At mesoscopic level, concrete is considered as a three-phase composite consisting of mortar matrix, coarse aggregate and interfacial transition zone (ITZ) between them. According to the grading of coarse aggregate obtained from sieve analysis, the random aggregate models with polygonal...

In this paper, the influence of aggregate size and volume fraction on shrinkage induced micro-cracking and permeability of concrete and mortar was investigated. Nonlinear finite element analyses of model concrete and mortar specimens were performed. The aggregate diameter was varied between 2 and 16 mm. Furthermore, a range of volume fractions between 0.1 and 0.5 was studied. The nonlinear anal...

The aim of this paper is to carried out statistical analysis for optimization of various concrete mix proportions by using full factorial experimental technique. The variables such as 28 days cube compressive strength, water to cement ratio (w/c), coarse aggregate to total aggregate ratio (CA/TA) and total aggregate to cement ratio (TA/C) were the parameters to be used for optimization. Four w/...