The Heifangtai Loess terrace in northwest China is frequently affected by landslides due to hydrological factors, establishing it as a significant research area for loess landslides. Advanced time-series InSAR technology facilitates the retrieval of surface deformation information, thereby aiding monitoring landslide status. However, existing methods that analyze patterns do not fully exploit displacement time series derived from InSAR, which hampers exploration potentially coexisting within...

The generation and development of interfacial adhesion properties between the asphalt binder aggregate surface is difficult to explain at microscale through experiments. In this research, models asphalt–aggregate interface were constructed using four-component molecules overlaid on two typical minerals aggregate, respectively. Then diffusion law aggregates behaviour analysed calculations coefficient, Z-axis direction relative concentration dipole moment. Moreover, distribution...

Polyurethane (PU) is a synthetic material available for researchers to be designed in terms of their demands. This study prepared novel polyurethane thermoplastic elastomer (PUTE) as an asphalt modifier through the reasonable selection raw materials and formula. The results Fourier transform infrared spectroscopy (FTIR) test confirm chemical reaction between ─ NCO groups PUTE prepolymer OH most polar molecules (asphaltenic regions). Effects modifications (1%, 3%, 5%, 7%, 9%, 11%, 13%, 15% by...

Compatibility between asphalt and polyurethane (PU) additives is the most challenging issue affecting performance of PU modified asphalt. This study aims to investigate influence shearing temperature content on compatibility via experiments molecular dynamics (MD) simulation. Herein, models base asphalt, molecules, PU/asphalt blends were first constructed in Materials Studio (MS) software. Based a reasonable model, storage stability was measured by calculating solubility parameters (δ)...

Abstract GNSS phase observable-specific signal bias (OSB) corrections are essential for widespread application of precise point positioning with ambiguity resolution (PPP-AR) or PPP-RTK. However, subject to the orbital error effects, conventional undifferenced (UD) model-derived BeiDou System (BDS) real-time (RT) OSB products usually unsatisfactory. In this study, a novel OSB-generating method assisted by double-differenced (DD) model is proposed. The reliable integer UD ambiguities obtained...

An understanding of the mechanical properties and macroscopic behavior unsaturated soil can be improved through an in-depth microscopic insight variables controlling soil–water characteristic curve (SWCC). In this study, effects initial conditions on pore structure SWCC silty was examined. Their relationships to during water loss addressed from both perspectives. patterns different those previous studies were revealed; especially pertained effect content SWCC. The obtained using repeated...

This study investigated the modification mechanism of polyurethane (PU) on high- and low-temperature properties asphalt based experimental molecular dynamics (MD) simulations. PU-modified was prepared using an in situ polymerization method. The containing various PU contents were via a series laboratory tests. model, PU–asphalt mixes system modeled software. Based reasonable models, influence content physical modulus motion at high temperatures researched MD glass transition temperature with...

Many modified Kozeny–Carman (KC) equations have been used to predict the saturated permeability coefficient (Ks) of porous media in various fields. It is widely accepted that KC equation applies sand but does not apply clay. Little information available clarify this point. The effectiveness will be evaluated via laboratory penetration tests and previously published data, which include void ratio, specific surface area (SSA), liquid limit (LL), values. This paper demonstrates how estimate SSA...

Considering the defects of insufficient low-temperature flexibility and high cost epoxy asphalt binder, low-cost polypropylene glycol (PPG) toluene diisocyanate (TDI) were used to synthesize two polyurethane (PU) prepolymers (PTPU) with different isocyanate group (─ NCO) contents, properties PTPU-modified binders mixtures studied. First, mixing parameters determined through tests, its storage stability, high- creep characteristics Then microscopic modification mechanism was explored....

The Laser Interferometer Space Antenna (LISA) mission is a joint ESA-NASA for detecting low-frequency gravitational waves in the frequency range from 0.1 mHz to 1 Hz, by using accurate distance measurements with laser interferometry between three spacecraft, which will be launched around 2015 and one year later reach their orbits Sun. In order operate successfully, it crucial constellation of spacecraft have extremely high stability. this paper, several problems orbit optimization LISA are...

For real-time (RT) precise point positioning (PPP), the state space representation (SSR) information is often delayed due to possible communication delays and specific broadcast intervals. In this case, results will diverge re-converge increase of SSR products extrapolation errors. addition, RT orbit clock offset accuracy, as well their errors, vary in different systems satellites. We propose a PPP with ambiguity resolution (PPP-AR) method that combines time-differenced carrier phase (TDCP)...

Global Navigation Satellite Systems (GNSS)-based technologies have become an indispensable part of current structural health monitoring (SHM) systems because the unique capability GNSS to provide accurate real-time displacement information. equipment with a data sampling rate up about 20 Hz has been widely used for this purpose. High-rate (typically 100 Hz) offer additional advantages in as some highly dynamic civil structures, such bridges, require high-rate capture behaviors. However,...

Calcium carbonate (CaCO 3 ) whisker, as a new type of microfibrous material, has been extensively used in the reinforcement cementitious materials. However, combined effect CaCO whisker and fly ash on mechanical properties materials under high temperatures was still unknown. In this study, coupling cement investigated. Two sets mortars were fabricated, including whisker-based mortar which contained 0 wt.%, 5 10 15 20 wt.% substitution 30 addition to substitution. Mass loss, compressive...