Micromechanical modeling of crack-aggregate interaction in concrete materials

Wang

Journal of Hazardous Materials

2008

154

Recycled demolished concrete (DC) as recycled aggregate (RA) and recycled aggregate concrete (RAC) is generally suitable for most construction applications. Low-grade applications, including sub-base and roadwork, have been implemented in many countries; however, higher-grade activities are rarely considered. This paper examines relationships among DC characteristics, properties of their RA and strength of their RAC using regression analysis. Ten samples collected from demolition sites are examined. The results show strong correlation among the DC samples, properties of RA and RAC. It should be highlighted that inferior quality of DC will lower the quality of RA and thus their RAC. Prediction of RAC strength is also formulated from the DC characteristics and the RA properties. From that, the RAC performance from DC and RA can be estimated. In addition, RAC design requirements can also be developed at the initial stage of concrete demolition. Recommendations are also given to improve the future concreting practice.

Section: Recycled Aggregate Concretementioning

confidence: 99%

Assessing relationships among properties of demolished concrete, recycled aggregate and recycled aggregate concrete using regression analysis

Wang

Journal of Hazardous Materials

2008

154

American Journal of Engineering and Applied Sciences

“…Based on finite element method, Deng et al (2010;Du et al, 2005;Li et al, 2016;Jin and Du, 2012;Du et al, 2012;Mohamed and Hansen, 1999) have carried out numerical simulation about mechanical properties such as uniaxial tension, uniaxial compression and shear-resistance and good results are obtained; Tao et al (2015) study on stress monitoring and strength analysis of step-by-step translation structure in electric drilling rig; Yu et al (2015a) Carried out the numerical simulation of casing stress and the influence factors of are analyzed. Tang and Xiang (2015) Yu et al (2015b) Mohamed and Hansen, (1999) studied the situation of crack penetrating aggregate; Liu (2003) Studied the influence of the thickness of protective layer on the fracture failure; Xu et al (2014) Wang et al (2012) Studied the influence of reinforcement ratio on rupture failure; Hu et al (2014;Hu and Mi, 2015) studied the influence of steel position on rupture failure; Hu and Mi (2015). Tang (2009), Li et al (2016 and Licheng et al (2012) studied the size effect of reinforced concrete; Zhang et al (2007) studied on the difference of mechanical properties of reinforced concrete and plain concrete in loading damage.…”

Section: Introductionmentioning

confidence: 99%

Numerical Simulation of Flexural-tensile Properties of Reinforced Concrete Beam

Shi¹,

Wang²,

Liu³

2017

Reinforced concrete is a kind of typical composite and reinforced concrete structure is widely used in the construction of a kind of structure, the flexural-tensile properties is very important for structure design optimization. In this study, the 2 dimensional numerical model of reinforced concrete beam is established by using ANSYS software and the effects of the thickness of the protective layer, the reinforcement ratio and the size of the specimen on the flexural performance of reinforced concrete beams are studied. The research shows that the failure of reinforced concrete beams is started in the middle and bottom of the beam and the influence of the specimen size on the failure load is the most significant, the mid-span stress increases with the decrease of thickness of protective layer and reinforcement ratio.

Proceedings of the 5th International Conference on Civil Engineering and Transportation 2015

“…Mohamed [3] have found that the failure of concrete was initiated from the microcracks happening in the interface between aggregate and mortar. By analyzing the failure mechanism of concrete, it is expected that deferring the occurrence and development of microcracks can improve the performance of concrete.…”

Section: Introductionmentioning

confidence: 99%

Mechanical properties of concrete made from aggregate saturated in concrete interfacial agent

Li¹,

Wu²,

Li³

et al. 2015

Abstract.Based on the fact that aggregate surface features have a great effect on the performance of concrete, a method for improving concrete performance by modifying aggregate surface features was proposed. Specifically, with aggregates immersed into concrete interfacial agent (CIA) suspension to increase the bond strength of interfaces between the aggregates and mortar, mechanical properties of concrete were improved. Two group experiments were carried out and the results show that concrete with coarse aggregates saturated in CIA has higher cubic compressive strength and lower discreteness of the strength than that of conventional concrete, and cement paste grade 52.5 has a better modification result than RH-1 paste.