Methods of specifying ready-mixed concrete

Large-scale recycling of new industrial wastes or by-products in concrete has become a crucial issue for construction materials sustainability, with impact in the three pillars (environmental, social and economic), while still maintaining satisfactory, or improved, concrete performance. The main goal of the paper is to evaluate the technological feasibility of the partial, or total, replacement of fly-ashes (FA), widely used in ready-mixed concrete production, with spent equilibrium catalyst (ECat) from the oil-refinery industry. Three different concrete mixtures with binary binder blends of FA (33.3% by mass, used as reference) and of ECat (16.7% and 33.3%), as well as a concrete mixture with a ternary binder blend with FA and ECat (16.7%, of each) were tested regarding their mechanical properties and durability. Generically, in comparison with commercial concrete (i) 16.7% ECat binary blended concrete revealed improved mechanical strength and durability; (ii): ternary FA-ECat blended binder concrete presented similar properties; and (iii) 33% ECat binary blended concrete has a lower performance. The engineering performance of all ECat concretes meet both the international standards and the reference durability indicators available in the scientific literature. Thus, ECat can be a constant supply for ready-mixed eco-concretes production, promoting synergetic waste recycling across industries.

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Testing and Green Assessment Technology for Ready-Mixed Concrete

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.768.306 ◽

2018 ◽

Vol 768 ◽

pp. 306-313 ◽

Cited By ~ 1

Author(s):

Chun Zhi Zhao ◽

Yi Liu ◽

Shi Wei Ren ◽

Jiang Quan

Keyword(s):

Quality Control ◽

Energy Conservation ◽

Building Material ◽

Rapid Development ◽

Green Building ◽

Process Quality ◽

Concrete Quality ◽

Assessment Technology ◽

Ready Mixed Concrete ◽

Mixed Concrete

Concrete is the most extensively used material in building and civil project structure. With the rapid development of economic construction, urban construction and infrastructure construction increase year by year, so there is a greater demand for concrete, which brings the rapid development of ready-mixed concrete industry. During the rapid development, structural safety and durability problems caused by concrete quality appear frequently. Meanwhile, to implement the fundamental national policies of resource conservation and environment protection, according to Green Building Action Plan (GUOBANFA [2013] No.1) approved by CPC Central Committee and the State Council, besides meeting the quality requirements, ready-mixed concrete must also meet the green products requirements of "energy conservation, emission reduction, safety, convenience and recyclability" for the vigorous development of green building material and supporting the requirements for building energy conservation, green building and new-type urbanization construction. By quality testing, this paper elaborates the green assessment technology for ready-mixed concrete in combination with raw material quality control, design of mix ratio, production process quality control, construction process quality control, residual concrete treatment, hardened concrete quality control, and control of dust, noise and wastewater. The greening of ready-mixed concrete brings the production and application of green building material, promotes the transformation and upgrading of building material industry and drives the development of green building.

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