Stability Problems on D-finite Functions

This paper continues the studies of symbolic integration by focusing on the stability problems on D-finite functions. We introduce the notion of stability index in order to investigate the order growth of the differential operators satisfied by iterated integrals of D-finite functions and determine bounds and exact formula for stability indices of several special classes of differential operators. With the basic properties of stability index, we completely solve the stability problem on general hyperexponential functions.Comment: 9 page

Study on simulation mechanics and fatigue performance of steel bridge deck rigid flexible composite pavement

Aiming at the fatigue cracking of steel bridge deck pavement and the shortage of river sand resources, a sea sand RPC pavement scheme was proposed. Taking Quanhe steel box girder bridge as the research background, the simulation model was established by using ANSYS finite element software, and the mechanical simulation analysis of the steel bridge deck sea sand RPC-asphalt pavement composite structure was carried out to determine the most unfavorable load position. A three-point fatigue test was carried out to study the fatigue performance of the structure specimen, and a comparative analysis was made with the river sand RPCasphalt surface composite pavement structure. The results show that the maximum tensile stress and strain of RPC-asphalt pavement appear in the upper middle span of U-shaped stiffener of steel box girder, which are 0.5241MPa and 98.2με, respectively, and the surface of the pavement in this area is prone to crack. The RPC-asphalt surface composite pavement structure has not been damaged after 2 million times of fatigue tests, and has not been damaged after 1 million times of fatigue loading after secondary loading, which indicates that it has better fatigue performance

Study on simulation mechanics and fatigue performance of steel bridge deck rigid flexible composite pavement

Aiming at the fatigue cracking of steel bridge deck pavement and the shortage of river sand resources, a sea sand RPC pavement scheme was proposed. Taking Quanhe steel box girder bridge as the research background, the simulation model was established by using ANSYS finite element software, and the mechanical simulation analysis of the steel bridge deck sea sand RPC-asphalt pavement composite structure was carried out to determine the most unfavorable load position. A three-point fatigue test was carried out to study the fatigue performance of the structure specimen, and a comparative analysis was made with the river sand RPCasphalt surface composite pavement structure. The results show that the maximum tensile stress and strain of RPC-asphalt pavement appear in the upper middle span of U-shaped stiffener of steel box girder, which are 0.5241MPa and 98.2με, respectively, and the surface of the pavement in this area is prone to crack. The RPC-asphalt surface composite pavement structure has not been damaged after 2 million times of fatigue tests, and has not been damaged after 1 million times of fatigue loading after secondary loading, which indicates that it has better fatigue performance