Desert sand is one of the current research hotspots in alternative materials for concrete aggregates. In the process of practical application, compressive strength is an essential prerequisite for studying other properties. Based on the current research situation, a prediction technology of compressive strength of desert sand concrete (DSC) is proposed based on an artificial neural network (ANN) and a particle swarm optimization (PSO). The technology is a prediction model that adjusts the network architecture by using the PSO method based on the ANN optimization model. Water-binder ratio, sand ratio, replacement rate of desert sand, desert sand type, fly ash content, silica fume content, air content, and slump were selected as the neural network’s inputs. The compressive strength data of 118 different combinations of influencing variables were tested to establish the dataset. The results show that the PSO method is efficient for the ANN in DSC compressive strength research. Furthermore, referring to this method, DSC is applied to the shotcrete of tunnels in construction engineering successfully, and the dust particle content during construction is evaluated.

As governments are increasingly attaching more importance to environmental protection, many policies and regulations are being promulgated to restrict or prohibit river sand extraction. Thus, there is a growing tendency for concrete production to use desert sand-doped artificial sand as the fine aggregate. This paper investigated the microstructure, mechanical properties, durability, and volume stability of concrete with desert sand and artificial sand. In the study, the strength grades of concrete ranged from C30 to C100, while the substitution ratios of the desert sand for the artificial sand ranged from 0 % to 100 %. The results showed that a high substitution ratio of desert sand increased the concrete porosity and extended the interface zone width. The concrete strength generally decreased as the desert sand substitution ratio increased, however, for the C50 and C60 strength grades, concrete with 20 % desert sand had minor positive effects. Basically, as the desert sand substitution ratio increased, the Cl-penetration resistance and frost resistance tended to be weaker, although there were a few exceptions. High substitution ratios of desert sand were also not good for the sulfate attack resistance of concrete. In most cases, concrete with 20 % desert sand shrank more slowly than concrete without desert sand. These conclusions provide the experimental support for the promotion of desert sand applications in the concrete industry.

In this paper, the manufactured sand was replaced by desert sand with contents to prepare desert sand concrete with different grades. Then the compressive strength, axial compressive strength, static compressive elastic modulus and axial tensile strength of desert sand concrete were tested to analyze the influence of desert sand replacement rate on the mechanical properties of concrete at different ages and different grades. It was shown that the negative influence of desert sand on the compressive strength of concrete would be increased with the increase of concrete grade, and the influence increased with the increase of age. The addition of sand would be resulted in the decrease of axial compressive strength and static elastic modulus of concrete, and with the increase of concrete grade, the strength would be decreased obviously. The addition of desert sand had no significant effect on the axial tensile strength of concrete in general.

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