Papers by Author: Jia Ying Sun

Abstract: In this article, the basic mechanical characters of recycled fine aggregate concrete (RFAC) are studied, and the relationships of recycled fine aggregate (RFA) content, minimum particle size and water content with them are also discussed according to results of cubic compressive strength （f¬¬cu）, flexural strength （ff）, splitting tensile strength（fts）, axial compressive strength（fc）and Yang’s modulus （Ec）. The results indicate that the use of RFA will induce mechanical properties of RFAC to deteriorate, and the deteriorated trend of it become more obviously with RFA content increased and minimum particle size reduced, in addition to, the early compressive strength of RFA develop slowly. The RFAC elastic modulus is significantly lower than ordinary concrete, besides, RFA on elastic modulus was significantly affected than other mechanical properties.

Abstract: Porous cement concrete, which has some superiority in environmental protection compared with normal concrete, has been more widely applied. Performance of Steel Slag and influence of the steel slag aggregate on physical and mechanical properties and durability of porous cement concrete were studied in this paper. Based on study of porous cement concrete properties, the paper puts forward several typical pavement structure forms in engineering application of porous cement concrete from finite element analysis method.

Abstract: Based on the experiments, the effect of waste gypsum on the formation of paste structure, the early strength and the stability of lime-fly ash is discussed in the article. As is shown by the results, the early strength of paste was improved by adding waste gypsum into lime-fly ash. The stability of lime-fly ash paste modified by waste gypsum could meet technical requirements when waste gypsum admixture was less than 40%. With the increase of hydration age, the number of ettringite (AFt) and C-S-H gel in paste would increase.

Abstract: In the light of heavy metal contents such as Pb and Zn in municipal sewage sludge exceeding the allowed maximum value of discharge wastes in China, new solidification technology was taken to solidify sewage sludge; its effect and safety were studied as well. The experiment results showed that the 28 days compressive strength of sewage sludge concretion were more than 40 MPa by this solidification method and a relative excellent advantage of road performance properties such as residual Marshall values and rutting resistance for asphalt mixture prepared with sewage sludge concretion. Meanwhile, its solidified heavy metal infusion met the requirements of the national standard, in other words, heavy metal ions receiving an effective bound and stable solidification.

Abstract: Influence of recycled aggregate on slump, compressive strength and chloride ion permeability of recycled aggregate concrete was investigated. As is shown by the results, although recycled aggregate belongs to the category of poor quality aggregate, the properties of high performance recycled aggregate concrete are not reduced dramatically with the increasing amount of recycled aggregate, for recycled aggregate have both positive effects and negative effects on the properties of recycled aggregate concrete. The high performance recycled aggregate concrete can be developed by double-mixture of ultra fine fly ash and superplasticizer.

Abstract: To tackle the annually increasing amount of municipal waste, this paper proposes a new consolidation technology to consolidate stale municipal waste, and elaborates on the consolidation effect and safety. Research results demonstrate that 28-day strength of municipal waste consolidation can be up to more than 38 MPa by this consolidation technology. Thus consolidation durability is better in terms of resistance to freezing, water, dry-wet circle and sulfate erosion. Meanwhile, its amount of leaching-out solidified heavy metal meets the requirements of national standard in China, in other words, heavy metal ions are effectively bound and stably solidified.