THE MULTI-FACTOR CONTROL AND EVALUATION OF HIGHWAY SOFT SOIL SUBGRADE STABILITY

When the surcharge preloading method is used in the treatment of soft soil subgrade, it is necessary to squeeze for more preloading drainage consolidation time under the premise of controlling the subgrade stability during the filling period. Considering the mutation of each monitoring indices and their interrelation when instability occurs in the fill subgrade, the inflection point analysis method through monitoring indices to control the subgrade stability comprehensively was proposed in this paper. The thin-layer rotary adding method was used to determine the ultimate filling depth and the loading plan for the highway soft soil subgrade during the filling period, with the inflection point analysis method in analyzing and evaluating the subgrade stability. The results showed that: (1) The ultimate fill height of the subgrade sections was obtained from the stability analysis results on the basis of the three indices of pore water pressure increment, settlement and lateral displacement, which was close to the prediction results of the thin-layer rotary adding method. (2) The stability control standard of the subgrade construction in the filling method was that the single-stage pore pressure coefficient should be within 1.2. (3) The subgrade stability control standard contained the maximum settlement rate of 20mm/d and the maximum lateral displacement rate of 3mm/d. (4) The geotextile setting in the highway subgrade effectively improved the ultimate bearing capacity of the subgrade, reduced the lateral displacement, improved the anti-slip stability, and increased the ultimate filling height and filling rate

Jointly Modeling Topics and Intents with Global Order Structure

Modeling document structure is of great importance for discourse analysis and related applications. The goal of this research is to capture the document intent structure by modeling documents as a mixture of topic words and rhetorical words. While the topics are relatively unchanged through one document, the rhetorical functions of sentences usually change following certain orders in discourse. We propose GMM-LDA, a topic modeling based Bayesian unsupervised model, to analyze the document intent structure cooperated with order information. Our model is flexible that has the ability to combine the annotations and do supervised learning. Additionally, entropic regularization can be introduced to model the significant divergence between topics and intents. We perform experiments in both unsupervised and supervised settings, results show the superiority of our model over several state-of-the-art baselines.Comment: Accepted by AAAI 201

Structural and Chemical Orders in Ni64.5Zr35.5 Metallic Glass by Molecular Dynamics Simulation

The atomic structure of Ni64.5Zr35.5 metallic glass has been investigated by molecular dynamics (MD) simulations. The calculated structure factors from the MD glassy sample at room temperature agree well with the X-ray diffraction (XRD) and neutron diffraction (ND) experimental data. Using the pairwise cluster alignment and clique analysis methods, we show that there are three types dominant short-range order (SRO) motifs around Ni atoms in the glass sample of Ni64.5Zr35.5, i.e., Mixed-Icosahedron(ICO)-Cube, Twined-Cube and icosahedron-like clusters. Furthermore, chemical order and medium-range order (MRO) analysis show that the Mixed-ICO-Cube and Twined-Cube clusters exhibit the characteristics of the crystalline B2 phase. Our simulation results suggest that the weak glass-forming ability (GFA) of Ni64.5Zr35.5 can be attributed to the competition between the glass forming ICO SRO and the crystalline Mixed-ICO-Cube and Twined-Cube motifs

Influence of Grassland Management on Carbon Allocation in a Semiarid Temperate Steppe

Grazing lands in North China are often excessively grazed and widely degraded, while hay-making lands appear to be in relatively good condition due to grazing exclusion, but they are facing a continuous loss of nutrients in the harvested biomass. In semiarid grasslands, plant productivity and community composition are significantly altered by grazing and haying. Grazing mostly leads to negative effects on aboveground productivity, however root biomass seems to increase with moderate grazing (Gao et al. 2009; Derner et al. 2006), although responses can vary. Aboveground biomass removal can increase C3 grass dominance and productivity (Hofer and Bragg 1981). Grazing exclusion is a valuable mechanism of sequestering soil C (He 2008). However, grazing can change C allocation patterns and affect the amount of C entering the soil. Here we examine the potential effects of common management practices (exclusion with fencing, grazing and hay-making) on semiarid grasslands above- and below-ground C pools. The primary objective of this study was to evaluate the potential of grazing exclusion and annual last-summer haying in previous grazing lands on the storage of C in semiarid grasslands of northern China