Introduction As a non-homogeneous material, concrete has a large number of microcracks and even macro-defects on its surface and inside. Cracks in concrete dams can impair the integrity of the dam, change its stress state, and shorten its service life. In practical engineering, most concrete structures are subjected to dynamic loads such as earthquakes and dynamic water pressure. Dynamic loading has uncertainty and complexity, which has an important impact on the load-carrying capacity and durability of concrete structures. Research on the crack resistance of concrete is conducive to delaying and mitigating the cracking of concrete as well as taking measures to stop the cracking of cracked concrete, thus improving the durability and safety of concrete structures.Dam concrete is usually fully-graded concrete, subject to various conditions usually uses wet-screening concrete to carry out experimental research, but its test results do not fully reflect the mechanical properties of fully-graded concrete due to the sieve out of the large aggregate. It is thus necessary to carry out the fracture test of fully-graded concrete. In addition, many concrete high dams in China are constructed in the southwest and northwest earthquake areas, and the existing research on the fracture under dynamic loading is seriously lack. This paper was to carry out tests during rapid loading to obtain the dynamic fracture parameters of fully-graded concrete.Methods Fully-graded concrete specimens were prepared using the same mix ratio as the Baihetan Arch Dam. The 15MN dynamic and static material was used and an axial tensile fracture test was carried out. The specimens had a diameter of 450 mm and a height of 450 mm. The central part of the concrete specimen was cut by a cutting machine to form a ring prefabricated crack with a depth of 45 mm and a ratio of the length of the prefabricated crack to the length of the ligament of 0.2.To compare the fracture properties of fully-graded concrete under static and dynamic loading, a strain rate of 10-6 s-1 was set as the quasi-static condition. According to the range of seismic characteristic strain rate, a strain rate of 10-3 s-1 was set as the dynamic working condition. The test was controlled via displacement loading, and the change process of load and loading point displacement was recorded during the test. At the cracks, one trans-seam displacement extensometer was arranged at every 90° degree along the ring, with a total of four extensometers at a distance of 50 mm, and the direction of the displacement extensometers was parallel to the length of the specimen, which was used to determine the change curve of the crack opening displacement with the load in the loading process. Laser displacement gauges were arranged adjacent to each of the displacement gauges at a distance of 350 mm to measure the overall deformation of the specimen. The fracture toughness was calculated via the experimental and numerical data, where the numerical method was an extended finite element method, and the eccentricity phenomenon that occurred during the test was also taken into account.Results and discussion All the specimens are fractured along the prefabricated crack surface. For the specimens under quasi-static loading, the fracture surface is rough and exposed more coarse aggregate, and the interface between aggregate and matrix stripping mostly appears on the fracture surface, and the fracture of aggregate is rare. In the specimens under dynamic loading, the fracture surface is slightly flat, and in addition to the interface between the aggregate and matrix stripping, a number of coarse aggregates are pulled off in the section. During the slow increase in load, the cracks tend to expand along the weak surface, i.e., the aggregate-matrix interface. Under dynamic loading, the cracks do not have time to develop along the weakest part but expand along the shortest path, leading to damage to the specimen.The increase in the strength of concrete specimens under dynamic loading is because the process of extension along the prefabricated cracks runs directly through the coarse aggregate, without having time to pass through the weak part of the cement mortar-coarse aggregate bond. In essence, the inertial forces and inhomogeneity of the concrete material itself lead to an increase in the strength of the specimens under dynamic loading. Under quasi-static loading, the rate of strain energy release and aggregation in concrete specimens is slower, and crack expansion occurs along the weak part of the material. In contrast, under dynamic loading, the rate of strain energy release and aggregation in concrete specimens accelerates and cracks may propagate through the stronger parts of the material, leading to an increase in strength.Conclusions The peak load, energy absorption capacity, fracture energy, and fracture toughness of fully-graded concrete specimens under dynamic loading were increased by 58.51%, 145.75%, 124.48% and 47.71%, respectively, compared to static loading, while the characteristic length was reduced by 11.67%. The numerical simulation calculated the fracture toughness taking into account the eccentricity phenomenon during the test, which was increased by 71.98% for quasi-static loading and by 60.35% for dynamic loading, compared to the uniform loading method without taking into account the eccentricity phenomenon.