Effect of early strength agent on cement slurry containing retarder

Retarders have an important regulation effect on the hydration speed and setting time of cement. However, retarders are not conducive to the early strength development of concrete, so use early strength agents to improve their early performance. In this paper, the effects of different amounts of triethanolamine (TEA) and citric acid (CA) on the...

Effect of ultra-fine fly ash on the mechanical and shrinkage properties of ultra-high performance concrete

This paper reports on a study to determine the possibility of using ultra-fine fly ash (UFA) for partial or total replacement of normal fly ash (NFA) in ultra-high performance concrete (UHPC). Workability, microstructure, porosity, drying shrinkage as well as mechanical properties were comprehensively studied to investigate the influence of UFA...

Effect of fine aggregate on rheological properties of ultra-high performance concrete（UHPC)

In this paper, four kinds of ecological fine aggregates (manufactured sand, recycled sand, aeolian sand and river sand) were used to prepared UHPC, the effects of the fine aggregates on the workability, rheological properties and mechanical properties of UHPC were studied. The results reveal that the type and content of fine aggregate have an...

3D Cadastre Oriented Reconstruction of Administrative Procedure in Chinese Urban Land Management

Focusing on the recent management problem of 3D land utilization in the administrative procedure in China, this paper firstly elaborates the basic characteristics of land ownership and management in China, and then introduces the main concepts and steps in the current urban land management procedure, and reveals the deficiency in supporting 3D...