Development and Investigation of a New Low-Cement-Consumption Concrete—Preplaced Aggregate Concrete

Abstract

Reducing consumption of cement in concrete will achieve huge benefits in decline of carbon emission, conservation of natural resources and reduction of the cost of concrete. In this paper, the low-cement-consumption concrete, preplaced aggregate concrete (PAC), is prepared and 12 types of mixtures including four water–binder ratios (W/B) and three sand–binder ratios (S/B) are designed to detect the effect of W/B and S/B on the mechanical properties and failure mechanism of PAC. Experimental and analytic results indicate that the cubic compressive strength of PAC, splitting tensile strength of PAC and elastic modulus of PAC decrease with increase in W/B and S/B. At a similar compressive strength, more than 20% increment of elastic modulus of PAC is achieved when compared with normal concrete (NC); the descent stage of stress–strain curves of PAC are steeper than that of NC and the peak strains of PAC is lower than that of NC. Guo’s model with suitable values of parameters a and b can be used to describe the stress–strain relationship of PAC. Replacing NC by PAC in concrete structures will save 15–20% cement and achieve great environmental and economic benefits.

Impact of the Geometrical Parameters of Dolomite Coarse Aggregate on the Thermal and Mechanic Properties of Preplaced Aggregate Concrete

“…In order to determine the compressive strength of concrete, 18 samples were tested, while the remaining ones were subjected to thermal tests. Preplaced aggregate concrete is prepared by placing coarse aggregate into formworks and then injecting the grout mortar into the void between the coarse aggregate [ 33 ]. The composition of the mix is presented in Table 2 .…”

Experimental and Analytical Modeling of Flexural Impact Strength of Preplaced Aggregate Fibrous Concrete Beams

“…According to the research of Rajabi et al [ 6 ], preplaced aggregate concrete outperformed ordinary concrete in terms of compressive strength, tensile strength, Young’s modulus, ultrasonic pulse velocity, and Schmidt hammer rebound number. Lv et al [ 13 ] reported that the preplaced aggregate concrete’s cubic compressive strength, splitting tensile strength, and elastic modulus all decreased when the ratio of water to binder and sand to binder increased. The elastic modulus of preplaced aggregate concrete might be increased by up to 20% when compared to conventional concrete at identical compressive strengths.…”

The properties of preplaced aggregate concrete technology contain the industrial waste-material and the various shapes and sizes of coarse aggregate

“…The first involves placing coarse aggregate into formworks while the second is injecting the potential grout into the void [1]. This method provides several benefits compared to the conventional concrete due to its flowability, absence of internal vibration, lower energy consumption, and cement weight [2][3][4]. However, one of the essential factors affecting PAC Technology is the quality of coarse aggregate and grout especially due to the influence of several factors such as the type of sand, cementsand ratio composition, water-cement ratio, and cement for conventional grout [5,6].…”