Abstract On December 18, 2023, the M S 6.2 Jishishan earthquake triggered a large-scale liquefaction disaster of loess sites in Jintian and Caotan villages, Zhongchuan town, Minhe County, Haidong City, Qinghai Province. To clarify micro-mechanism disaster, Q 3 Malan layer site its overlying red silty clay samples were selected quantitatively analyzed for differences physical properties, structure, microstructural parameters, mineral compositions. Based on discrepancy results,...

Loess is a Quaternary sediment with special properties including seismic vulnerability and water sensitivity. It prone to landslides, subsidence, liquefaction under earthquakes. As an environmentally friendly economical material, lignin can effectively improve the performance of loess appropriate dosage. However, study wave velocity characteristics in lignin‐modified (LML) sites still insufficient. Based on laboratory test results LML, this paper comprehensively uses methods field regression...

To develop a new modification method with environmentally friendly and seismically resistant characteristics for saturated loess foundations, lignin extracted from paper industrial wastes was selected mixing into the loess. Mixtures different contents were prepared under static pressure. A series of dynamic triaxial tests performed by applying sine loads after lignin-modified specimens consolidated on apparatus. The microstructural images mineral components modified investigated scanning...

Freeze-thaw cycles caused by climate change can the structure and strength of soil. In seasonally frozen soil areas, use improved loess as a filling material must consider effects freeze-thaw cycles. With increasingly severe global environmental problems, search for suitable new protection improvement materials has become one hotspots in performance research. The purpose this paper is to lignin fiber improve engineering resistance reduce negative impact construction on environment area....

The road subgrade and surface in collapsible loess area are prone to many engineering diseases such as uneven settlement, insufficient bearing capacity of soaked foundation, collapse instability side slope due the special properties loess. As an environment-friendly, low-cost soil modifier with good adhesion chelation properties, lignin has been considered be used highway construction. In order explore effect on loess, compressive modified different contents were analyzed based consolidation...

The dynamic stress–strain relationship of a saturated loess modified using different fly ash contents is studied based on triaxial tests. between the behaviour and content determined. Combined with SEM test results, seismic-resistant mechanism ash-modified analysed. results show that constitutive obeys hyperbolic model. model parameter minimum when 20%. However, increase in content, b decreases, modulus increased, whereas damping ratio reduced. When weight proportion approximately 25%,...

In the seasonal permafrost region with loess distribution, influence of freeze-thaw cycles on engineering performance reinforced must be paid attention to. Many studies have shown that use fiber materials can improve soil and its ability to resist cycles. At same time, as eco-environmental protection has become focus, which been more to, it a trend find new environmentally friendly improved replace traditional chemical additives. The purpose this paper uses environmental-friendly reinforce...

To effectively improve the poor engineering properties of loess and enhance its seismic performance, industrial by-product lignin is used as a modified material. Based on lots dynamic triaxial tests, elastic modulus damping ratio lignin-modified were tested. The effects content analyzed. Combined with scanning electron microscopy (SEM) X-ray diffraction (XRD), microscopic mechanism to was studied. results show that can modify deformation under load. Under same stress condition, strain...

To study the dynamic characteristics and mechanism of saturated loess after freeze-thaw cycles, a series laboratory tests including cycle tests, triaxial scanning electron microscope remolded was conducted. The parameters different cycles were discussed. microstructure changes analyzed. evolution process under proposed. results show that stress-dynamic strain curves conform to hyperbolic model; however, has significant effect on model parameter <math...

The 1927 Gulang Mw 8.0 earthquake was one of the largest earthquakes in Gansu, China, which triggered lots loess landslides. However, study area is atypical and different from that Loess Plateau. Meanwhile, there are few systematic research studies on characteristics these seismic Combined with previous field investigations, landslide distribution has been revealed through visual interpretation remote sensing images area. relationships between landslides various influencing factors have...

Abstract With the increasing demand for filling engineering construction in Loess Plateau, problems related to saturated loess caused by rainfall and irrigation are also increasingly prominent. This work studied shear characteristics of compacted experiments, qualitatively quantitatively explained meso-mechanism effect compaction degree on combined with meso-pore characteristic parameters. The study shows that stress–strain curve under 80 85% is strain softening, it weak softening 90%...

Metastable loess soils can deform, inducing geological and engineering disasters. Therefore, the behavior of under dynamic load is gaining massive attention from researchers to improve strength soils. Fly ash mixed with reduce construction costs environmental pollution. Moreover, it has strong economic social benefits. This paper investigates influence fly on properties modified through a series triaxial tests different contents. The treated soil samples were prepared using static compaction...

On 18 December 2023, a 6.2-magnitude earthquake struck Jishishan, affecting multiple counties and cities in Gansu Qinghai Provinces. The seismic intensity of the meizoseismal area was VIII, resulting extensive structural damage building collapses. A assessment conducted epicenter surrounding high-intensity zones. To understand typical structures characteristics buildings that were damaged these zones, this study summarizes to rural houses, compares houses across different sites, analyzes...

The soil-water characteristic curve plays a significant role in describing the unsaturated soil characteristics, and is greatly affected by stress state, wetting drying cycles other factors. Accurate measurement of key to mechanics studies. In this paper, based on GCTS (SWCC) instrument, undisturbed loess was tested study effects one-dimensional consolidation stress, history loess. experimental results show that: (1) As axial increases, air intake sample gradually decrease water content...

Dynamic triaxial tests are carried out on loess from different regions in Shanxi province. Based the test results, dynamic constitutive relation, modulus and damping ratio behaviors of studied. Influence regional distribution, physical indexes ages analyzed by comparing model parameters. The results show that relation conforms to hyperbolic model. relationship between shear strain can be described as a negative exponential function. However, obeys power maximum tends increase south north....

To reduce the seismic damage of loess foundation through modification treatment, a series static and kinetic triaxial tests saturated loess- lignin mixed specimens were conducted. The dynamic constitutive relation strengthened by was investigated. relationship between content parameters including modulus, damping ratio, cyclic shear stress ratio path discussed. A suggestion optimal for improving resistance using proposed. Besides, strengthening mechanism modified determined combined with...