Case study of sand bag well applied on soft soil reinforcement in road widening project
Based on the case study of soft soil reinforcement on Baian interchange, Gaofu Road, Shunde District, Foshan, the designing method and monitoring program of sand bag well applied on the soft soil reinforcement in road widening project were introduced systematically. The settlement monitoring results during the preloading process indicated that the raise of the preloading height significantly increased the consolidation and settlement of soft soil ground. The settlemental rate was much greater at the beginning and medium-term of the preloading. While during the later proloading and the followed consolidating period, the settlement rate slowed down obviously. Therefore, it is very important to control the magnitude of each loading grade and the settlement rate at the beginning and medium-term of preloading. It was found that there was a desirable reinforcement effect and economic benefit applying sand bag well method to consolidate the soft soil ground at the case of overpass extension engineering in road widening project. The sand bag well method is valued being applied in similar projects.
Observational settlement prediction by curve fitting methods
The theoretical foundations of observational settlement prediction by methods of curve fitting are discussed. The fundamentals and the characteristics of the four methods (exponential, hyperbolic, Asaoka and logistic curves methods) are compared. Based on the observational settlement data of eight practical projects, the advantages and shortcomings of these methods are studied. Finally, several key problems for observational settlement prediction are put forward.
L-band 3D imaging of an Alpine Glacier: Results from the AlpTomoSAR campaign
In this paper we present results from the tomographic analysis of L-Band SAR data acquired in February/March 2014 over the Mittelbergferner glacier, Austrian Alps, during the ESA campaign AlpTomoSAR. The campaign includes coincident in-situ measurements of snow and ice properties, as well as high-frequency Ground Penetrating Radar (GPR) data acquired over a total length of 18 km. The analyses of three-dimensional TomoSAR data cubes shows the complexity of the glacier sub-surface scattering. Most areas are characterized by surface scattering in proximity of the Lidar surface, plus a complex pattern of in-depth volumetric scattering beneath. Various subsurface features observed in GPR transects at 600 MHz and 200 MHz clearly showed up in TomoSAR sections as well. In particular: firn bodies, crevasses, and even the bedrock down to 50 m below the ice surface.