Effects of generally anisotropic crustal rocks on fault-induced displacement and strain fields

We present a new solution for the elastic displacement and strain fields on or near Earth’s surface due to rectangular faults in an anisotropic half-space,expressed as a summation of(A)the solution in an infinite space which is singular,and(B)the complementary part which is regular and well-behaved.These two solutions are expressed in terms of the mathematically elegant and computationally powerful Stroh formalism and can be applied to the generally anisotropic rock half-space or a transversely isotropic rock mass with any oriented plane of isotropy.For any flat fault of polygonal shape,one needs only to carry out a simple line integral from 0 to 7 r in order to express the fault-induced response.Numerical examples are presented to demonstrate the significant effect of the rock anisotropy and layer orientation on the fault-induced displacement and strain fields in anisotropic rocks.Potential applications are wide ranging,from faults in sedimentary strata to strongly deformed metamorphic rocks with steeply dipping foliation.

Molecular dynamics simulation on the rejuvenation effects of waste cooking oil on aged asphalt binder

Waste cooking oil(WCO)has received attention on rejuvenating aged asphalt binder widely in recent years.This study evaluated the rejuvenation effects of WCO on aged asphalt binder on the micro-scale using molecular dynamics(MD)simulation.First,the representative molecules of WCO and asphalt binders were selected.The molecular mixture model was then developed.The thermodynamic properties were investigated,including density,cohesive energy density,solubility parameter,and surface free energy.The results show that WCO can restore the thermodynamic properties of aged asphalt binder to some extent and WCO has different influences on electrostatic interactions and van der Waals effects.From the diffusion behavior and molecular structure of asphalt binder,WCO can improve the molecular mobility and restore the colloidal structure.Besides,the adhesion work and moisture susceptibility of asphalt binder-aggregate interfaces(calcite and quartz)were evaluated.The results show that WCO can improve adhesion work between asphalt binder and aggregates since WCO can change molecular structure of asphalt binders and certain adhesion work exists between WCO and aggregates.Also,it can mitigate the moisture susceptibility of asphalt binder-aggregate interfaces(calcite and quartz).The study demonstrates that the MD simulation can help to understand the rejuvenation effects of WCO on aged asphalt binder on the micro-scale.

A hybrid data-mining framework for train rescheduling strategy pattern discovery

This study presents a hybrid data-mining framework based on feature selection algorithms and clustering methods to perform the pattern discovery of high-speed railway train rescheduling strategies(RSs).The proposed model is composed of two states.In the first state,decision tree,random forest,gradient boosting decision tree(GBDT)and extreme gradient boosting(XGBoost)models are used to investigate the importance of features.The features that have a high influence on RSs are first selected.In the second state,a K-means clustering method is used to uncover the interdependences between RSs and the influencing features,based on the results in the first state.The proposed method can determine the quantitative relationships between RSs and influencing factors.The results clearly show the influences of the factors on RSs,the possibilities of different train operation RSs under different situations,as well as some key time periods and key trains that the controllers should pay more attention to.The research in this paper can help train traffic controllers better understand the train operation patterns and provides direction for optimizing rail traffic RSs.