Comparative Studies of Dynamic Mechanical Properties of Desert Sand Concrete and Ordinary Concrete

Qiaoli Chen,Li Han,Yiying Wang,Haifeng Liu,Shaofeng Wang

doi:10.1155/2022/8680750

Abstract

Ningxia is located in the western part of China, which abounds with desert resources. The application of desert sand in concrete has not been fully studied. In order to study the failure mechanism of desert sand concrete under impact loading, dynamic impact experiments on desert sand concrete and ordinary concrete were carried out by using the 74 mm diameter split Hopkinson pressure bar (SHPB) experimental apparatus. The dynamic mechanical properties of desert sand concrete under different impact velocities were analyzed. The random distribution program of round coarse aggregate in desert sand concrete was designed to generate the random distribution of coarse aggregate by ANSYS/APDL language. The dynamic failure process of single-graded concrete and two-graded concrete was numerically simulated and compared. The results showed that desert sand concrete and ordinary concrete have obvious rate-dependent effect. Detailedly, the ordinary concrete is totally destroyed when impact velocity is 10 m/s, but the desert sand concrete still maintains the cone shape at impact velocity of 18 m/s, which indicates that the impact resistance of desert sand concrete is better than that of ordinary concrete. When impact velocity is 5 m/s, the single-graded concrete and two-graded concrete are both destroyed, but the desert sand concrete is not damaged. When impact velocity is 10 m/s, the dynamic failure mode of single-graded concrete, two-graded concrete, and desert sand concrete is basically the same. When impact velocity is 15 m/s, the single-grade concrete shows different dynamic failure mode from that of desert sand concrete and two-graded concrete.

Highlights

Concrete is commonly used in civil engineering material
Comparison of Dynamic Failure Mode of Desert Sand Concrete and Single-Graded Concrete. e failure of different materials under different stress states is different, which is related to the properties of the materials themselves [55, 56]. e failure process of concrete activates its internal microcracks under the dynamic loading, and the microcracks expand into nucleation, growth, and merger to form macrocracks, which become the release stress zone and form cumulative damage
When the impact velocity is 5 m/s, there are no obvious microcracks on the specimen, and the desert sand concrete is not destroyed, which is in good agreement with experimental results

Summary

Introduction

Concrete is commonly used in civil engineering material. For better understanding of concrete, many researchers are devoted to studying the properties of concrete materials and concrete structures [1,2,3,4,5]. Many researchers have carried out studies on the engineering properties of desert sand concrete [7,8,9,10,11,12,13,14,15,16,17,18], but research on its dynamic mechanical properties has just started. Jones [21] carried out an experimental study on the relationship between loading rate and compressive strength of concrete, which becomes another milestone for the development of dynamic mechanical properties of concrete. Apart for experimental studies, many researchers simulated the dynamic mechanical properties of concrete by numerical simulation [38,39,40]. E finite element analysis software ANSYS/LS-DYNA was utilized to simulate the single-graded concrete and twograded concrete under impact loading, and the dynamic failure process was simulated to reveal the dynamic failure mechanism of desert sand concrete. e experimental results provide a guiding significance for the popularization of concrete and a theoretical basis for the application of desert sand concrete in civil engineering and hydraulic engineering

Experimental Investigations

Results and Analysis

Conclusions