Search

To study the influence of bond-slip on the numerical simulation of steel reinforced lightweight concrete (SRLC) members, the push-out test and finite element analysis are carried out first, and then the nonlinear finite element simulation of SRLC beams is conducted. The calculated results are compared with the experimental results. Four factors as the concrete protective cover thickness, stirrup ratio, concrete strength and anchorage length of section steel are considered in the test. The constitutive relation of interface bonding slip be-tween the section steel and light concrete is introduced in the finite element analysis based on the test results. Finite element analysis of pushout specimen's results indicate that the normal stress of the section steel is the same on the same cross section and the stress gradient gradually decreases from the loading end to the free end. Specimens with equivalent restraint coefficient γe less than 0.01 will be subjected to split failure and those specimens with the coefficient γe greater than or equal to 0.01 will be subjected to push-off failure. The bearing capacity and slip value obtained by finite element computation is consistent with experiment results. The stress distribution, crack shape and loaddeflection curve are analyzed in numerical simulation of SRLC beams. Influence factors involving shear span ratio and position of section steel are considered. Analysis results show that the mechanical properties of the SRLC beams are like that of the steel reinforced normal concrete (SRNC)beams. Diagonal shear failure is gradually transformed into flexural failure with the shear span ratio increasing. The load- deflection curve is obviously divided into three stages. Finite analysis results considering the slip between section steel and concrete agree well with the test results, while the capacity and stiffness without considering the slip are bigger than the experimental values. [ABSTRACT FROM AUTHOR]

Discusses the use of computer simulation for studying the microphase separation of a two-dimensional diblock copolymer system under directional quenching. Time evolution of the domain morphologies; Faster growth rate of the triangular phase with the increase of the initial thermal fluctuation.

The exploration on the microscale transport phenomena is of great significance to understand the mechanism of microscale mixing and chemical reaction in a rotating packed bed (RPB). In this paper, numerical investigation is carried out and compared with the experimental results. Two different scale reaction models are applied to simulate and the numerical result is in reasonable agreement with the experimental results. The fluid flow and the species transfer with a competitive and consecutive reaction are studied to obtain the evolution of the segregation index and flow field. Each environment changes and is updated continuously with the liquid film flowing outward, and the micromixing and reaction are influenced by the fractions p 1 and p 2 of different environments. It is evidenced that different factors such as rotational speeds, volume ratios and initial mixing concentration impose considerable influences on the micromixing and reaction processes. The micromixing time ranges about 5.2 × 10 −2 –1 × 10 −3 ms showing that micromixing performance in RPB is much better. The main product and by-product appear different evolution pattern along the package wires, which provide guideline for the optimization of RPB structure. The optimization on the RPB structure is provided and the simulation results clarify a deeper understanding on the micromixing and reaction features in RPB. [ABSTRACT FROM AUTHOR]

Based on the preview optimal simple artificial neural network driver model (POSANN), a new driver model, considering jerky dynamics and the tracing error between the real track and the planned path, is established. In this paper, themodeling for the drivervehicle system is firstly described, and the relationship between weighting coefficients of driver model and system parameters is examined through test data. Secondly, the corresponding road test results are presented in order to verify the vehicle model and obtain the information on drive model and vehicle parameters. Finally, the simulations are carried out via CarSim. Simulation results indicate that the jerky dynamics need to be considered and the proposed new driver model can achieve a better pathfollowing performance compared with the POSANN driver model. [ABSTRACT FROM AUTHOR]