Increase In Pore Water Pressure Research Articles

Vertical Capillary Barriers and Wick Drains to Mitigate the Rain-induced Slope Failures: Numerical Analysis

Slope failures are catastrophic when they suddenly occur in human habitats. The stability of slopes gradually diminishes with heavy rainfall due to the increase in pore water pressure; subsequently, the shear strength of the slope soil decreases. The effect of rainwater on the instability of slopes was studied in this research with respect to factor of safety values. Accordingly, finite element analysis and limit equilibrium analysis were conducted using a 2D model of a soil slope in SEEP/W and SLOPE/W programs to observe the responses of the slope soil profile under heavy rainfall. Movement of the wetting front and the fluctuation of the groundwater table were studied to develop a drainage mechanism, thereby to control the effect of infiltrated rainwater on slope failure. A conceptual method was introduced in this study by developing a numerical model with an effective drainage system which consists of vertical capillary barriers with combination of horizontal wick drains in a cascade manner in the slope. This method exhibited high stability of the slopes even with continuous rainfall for number of days, therefore, applicable as a sustainable prevention method of slope failures.

Effects of Shallow Groundwater on Deep Groundwater Dynamics in a Slow-Moving Landslide Site

A slow-moving landslide is a mass movement that has major societal impact because of its large sediment volume. The principal cause of landslides is increased pore water pressure in deep aquifer close to the slip surface. Elucidation of the behavior of deep groundwater is critical in the stability analysis of the slow-moving landslides. Shallow groundwater, which flows through the landslide regolith, can undergo vertical infiltration and thus make a major contribution to the formation of deep groundwater, but this has not been sufficiently elucidated. The aim of the present study was to investigate the effects of shallow groundwater on the dynamics of deep groundwater in a landslide regolith. At a landslide site, with an area of 4200 m2, the shallow and deep groundwater levels were observed. A 1-m-depth temperature survey and groundwater quality analysis were also performed. Water budget analysis using the groundwater level showed that in the former half of a major rainfall event, groundwater that infiltrates vertically in the landslide regolith plays a central role in raising the deep groundwater level. In addition, the preferential flow from shallow to deep aquifers is suggested to be important in that infiltration. The results of this study emphasize the importance of including the preferential flow from the shallow aquifer when modeling dynamics of deep groundwater.

Mechanism Study of Differential Permeability Evolution and Microscopic Pore Characteristics of Soft Clay under Saturated Seepage: A Case Study in Chongming East Shoal

Artificial reclamation is one of the main means of land expansion in coastal cities. However, the permeability of underlying soft clay (USC), derived from the dredged load, has not been paid enough attention, although it is closely related to the long-term deformation and stability of foundation soil. Hence, this paper analyzes the relationship between permeability characteristics and microscopic pore characteristics of USC in Chongming East Shoal (CES), a typical multi-phase reclamation area, through a variable head permeability test, mercury intrusion porosimetry (MIP) test, and scanning electron microscope (SEM) test. Furthermore, grey relation entropy and Pearson correlation analysis are implemented to analyze the influence of micropore parameters on permeability. The results revealed that the seepage process of clay showed a transition from unstable seepage to relatively stable seepage. Meanwhile, the permeability coefficient (PC) attenuated with time cyclically, indicating the alternating effect of the closed and opened unstable seepage channels. During seepage, clay particles could be entrained by pore water and intercepted by pores, thus clogging seepage channels. Then, the increased pore water pressure could break through new seepage channels. The degree of pore clogging was positively correlated with the average cycle period of PCs, and this was also present in the relatively stable stage of PCs. A lower mesopores content, higher fractal dimension, and aggregated flocculate microstructure could promote the clogging effect and result in lower permeability efficiency. Affected by unstable seepage channels, soft clay may face long-term potential deformation in the future, which needs further investigation.

Creep Characteristics and Creep Model of Coal Based on Pore Water Pressure

Anthracite in a specific area of Shanxi Province is the subject of this essay’s research. In the creep studies, different porosity intervals and pore water pressures were employed to evaluate the mechanical properties of creep under various test paths. The conventional Burges model was coupled in series with the nonlinear viscous elements and plastic elements. The key parameters in the equation are fitted, and a creep model is created to describe the nonlinear viscosity-elastic-plastic characteristics of coal under the influence of pore water pressure with varying porosities. The creep tests used varied porosity intervals, pore water pressures, and test paths to study the mechanical properties of creep. The conventional Burges model was coupled in series with the nonlinear viscous element and plastic element. To represent the nonlinear viscosity-elastic-plastic properties of coal under the effect of pore water pressure with variable porosities, the main parameters in the equation are fitted, and a creep model is developed. The results show that the porosity and strength of the coal sample are negatively correlated. In comparison to coal samples with a porosity of 5–10%, the uniaxial compressive strength of coal samples with a porosity of 10–15% and 15–20% reduced by 9.6% and 22.3%. Throughout the creep process, instantaneous strain rises with porosity, and changes in pore water pressure and porosity have an effect on instantaneous creep under low-stress loading, resulting in different creep curve starting strain values. The duration from stress loading to the accelerated creep stage in the failure stage and the time from the deceleration creep stage to the accelerated creep stage are both gradually shortened with an increase in porosity and pore water pressure. For regression analysis and parameter identification, a creep constitutive model was developed to describe the creep characteristics of coal samples with varying porosity under varying pore water pressure. The creep parameters of the new constitutive model were obtained, and they could very well reflect the creep characteristics of specimens with varying porosity intervals under the influence of pore water pressure.

Experimental study on dynamic behavior of polyacrylamide-reinforced tailings.

Earthquakes are a significant factor that contributes to tailings dam failure. Generally, the seismic stability of a tailings dam can be increased by improving the dynamic properties of tailings. The dynamic properties of tailings can be improved effectively using polymers. In this study, the dynamic properties of polyacrylamide-reinforced tailings were investigated via a sequence of dynamic triaxial tests. The content of polyacrylamide in the test sample was 0.3%. Test results show that the cyclic liquefaction resistance, initial dynamic shear modulus, dynamic shear modulus, and dynamic shear modulus ratio of polyacrylamide-reinforced tailings were slightly greater than those of unreinforced tailings. The damping ratio of polyacrylamide-reinforced tailings was lower than that of unreinforced tailings when the dynamic shear strain exceeded 0.038%. The increase in the dynamic pore water pressure of polyacrylamide-reinforced tailings during cyclic loading decelerated significantly compared with that of unreinforced tailings. The revised Zeng model can effectively described the changes in dynamic pore-water pressure of unreinforced and polyacrylamide-reinforced tailings. The polyacrylamide can improve the structural stability of the tailings specimen and also improve the dynamic properties of the tailings, thereby enhancing the seismic stability of the tailings dam.

The Permeability Evolution of Sandstones with Different Pore Structures under High Confining Pressures, High Pore Water Pressures and High Temperatures

Seepage from the pores of sandstone exposed in deep mines is difficult to block by grouting. In this paper, the permeability evolution of four subcategories of sandstone with different pore structures under different confining pressures, pore water pressures and temperatures is analyzed by experiments. (1) With increasing confining pressure, the permeabilities of the four tested subcategories of sandstone all decrease, but at different rates and to different extents. (2) With increasing pore water pressure, the permeability of subcategory I1, I2 and II1 sandstones increases linearly, while that of subcategory II2 sandstone decreases following a power function under low confining pressures and tends to be stable under high confining pressures. (3) With increasing temperature, the permeabilities of the four sandstone subcategories decrease at different rates. (4) The orthogonal experimental results show that the confining pressure has the greatest influence on the permeability, followed by the water pressure and temperature. (5) The confining pressure, pore water pressure and temperature produce stress-strain in sandstone and thus change the sandstone pore structure and permeability. The permeability evolution of sandstones varies with pore structure. The findings of this study can inform the classified grouting of deep sandstone and optimize grouting parameters.

One-dimensional non-linear rheological consolidation of clayey soils with Swartzendruber's flow law

Considering the non-linear creep characteristics of clays, the modified unified hardening (UH) relation is employed to reflect the visco-elastic-plastic deformation of soft soils. Simultaneously, Swartzendruber's flow in the form of a continuous function is captured to describe pore water flow through pores during consolidation. Thus, an upgraded one-dimensional (1-D) non-linear rheological consolidation (NRC) system of clays has been established, and its solutions are conducted using the finite volume method (FVM). Through comparisons against the theoretical solutions and laboratory test results, the effectiveness of the numerical algorithm and applicability of the modified UH relation is verified. Then, the effects of model parameters on non-linear rheological consolidation behavior were studied. The results indicate that ignoring the time effect of secondary consolidation coefficient overestimates the overall consolidation and settlement proceeding, and considering the viscous effect of the soils led to an unanticipated increase in excess pore-water pressure (EPP) at the initial loading period. Meanwhile, the rising EPP becomes more pronounced with the increase of the initial over-consolidated parameter, flow parameter, and soil thickness or the decrease of overlying load. Additionally, FVM and finite difference method (FDM) solutions, as well as the application scope of Darcy's law in the NRC system, are discussed.

A conceptual model for the shakedown response of soft clay to high-cycle, low-amplitude undrained loading

Soft soils beneath transportation infrastructures suffer dynamic traffic loads with high-frequency and high-cycle characteristics, which mainly present shakedown development of deformation yet probably induce notable deformation at the stable state. However, conventional constitutive models are still not available for the long-term behavior description of soft soils under high-cycle traffic loading. Herein, a conceptual model for high-cycle, low-amplitude undrained loading was proposed incorporating a shrinking yield surface and an expanding boundary surface, which individually indicated the weakening behavior caused by an increase in excess pore water pressure and the hardening effect due to contractive plastic deformation. Given the shakedown responses of soft soils, a mapping ratio and a one-time calculation approach were employed. Thus, the effect of loading frequency on the response of soft soil can be considered, and the calculation efficiency was greatly improved. Then, the evaluation of model parameters and parametric analyses on the loading frequency, shrinking yield surface, expanding boundary surface and mapping ratio were carried out to examine the performance of the proposed model. To further validate the proposed model, undrained cyclic triaxial tests on reconstituted Ningbo clay were conducted, and high-cycle undrained triaxial tests on Kaolin clay and Ariake clay were referenced. The predicted developments of accumulated plastic deviatoric strain and excess pore water pressure with the number of load cycles reached acceptable consistencies with the experimental results. Moreover, the effects of confining and deviatoric stresses were investigated. Not only rational developments of excess pore water pressure and plastic deviatoric strain but also nearly identical results under the same cyclic stress ratio (CSR) were obtained, which adequately confirmed the feasibility and reliability of the proposed model. Although this model was developed based on isotropically consolidated soils and contained varied parameters for different CSRs, it provides a framework contributing to rigorous model development for high-cycle conditions.

Excess pore water pressure behavior of saturated soft clay under cyclic confining pressure with different frequencies

The excess pore water pressure is main factor affecting the dynamic response of saturated soft clay under traffic loads. Recognize that, cyclic triaxial tests with and without cyclic confining pressure were carried out to study the development of excess pore water pressure of saturated soft clay. The impacts of factors, such as cyclic stress ratio (CSR), loading frequency, and cyclic confining pressure, were analyzed. Excess pore water pressure increases with increasing cyclic stress ratios, while decreases with increasing loading frequencies. Nevertheless, with increasing cyclic confining pressures, the maximum excess pore water pressure increases, while the minimum excess pore water pressure remains unchanged. Besides that, the greater CSR and cyclic confining pressure deliver an increment of both maximum and minimum excess pore water pressure rate. However, the excess pore water pressure rate - time curves coincide under different loading frequencies. Meanwhile, both the normalized maximum and minimum excess pore water pressure rates are linearly proportional with time under different test conditions in logarithmic coordinates. Based on that, both maximum and minimum excess pore water pressure prediction models, relating to the above factors, are proposed, and the predicted results accord well with the measured data.

Probabilistic Soil Liquefaction Assessment: A Case Study for Agartala City in Tripura in North-East India

A sudden increase in pore water pressure causes the effective stress to decrease significantly, which in turn causes a loss of shear strength and the subsequent outcome of allowing the soil to behave as a liquid, resulting in soil liquefaction. Agartala, the capital of Tripura, is located in northeastern India, and the entire region is considered seismically active according to the seismic zoning map of India as per IS 1893:2002 (Part 1); the entire region is classified as Zone-V. Significant earthquakes have struck this region, including the 1897 Shillong and 1950 Assam earthquakes. The city is vulnerable to liquefaction due to alluvial soil and a low groundwater table. Several parameters are involved in assessing liquefaction potential in the deterministic method and have different input parameter uncertainties, resulting in inconsistent outcomes. As a result, evaluating liquefaction susceptibility requires a thorough probability approach that considers parameter uncertainty. In this work, the soil liquefaction potential of Agartala City is assessed using fuzzy logic and compared to the conventional Reliability technique using the first-order second-moment method. Soil liquefaction potential was properly calculated using both approaches for the 71 boreholes in and around Agartala city. The outcomes are shown as contour maps representing spatial variations of the probability of liquefaction at different depths. In this study, Fuzzy logic is used to model the relationships between different soil parameters, which can help better understand the soil\'s behaviour during liquefaction. This developed method can assess the vulnerability of liquefaction potential and select appropriate materials and construction processes.

Liquefaction potential in the governor's office of West Sulawesi after the 2021 Mamuju-Majene earthquake

The Governor's Office of West Sulawesi Province is close to an active fault, which triggers its vulnerability to seismic activity. The Mamuju Majene Earthquake destroyed the Governor's office building with a magnitude of Mw 6.2 in 2021. The geological conditions at the site are alluvial deposit formations. In addition to the geotechnical conditions, it has the characteristics of sandy soil with fine to medium gradations. Liquefaction causes a loss of soil strength and an increased pore water pressure caused by vibrations on the earth's surface in the form of seismic waves. It causes a decrease in effective stress, ground settlement, and lateral spreading. This study aims to determine the potential for liquefaction in The Governor's Office of West Sulawesi using a simplified procedure method with a Standard Penetration Test (SPT). The Peak Ground Acceleration (PGA) value is determined using the RSA Human Settlements. The Liquefaction Potential Index (LPI) produces five zones of liquefaction potential levels. The analysis showed that The Governor's Office of West Sulawesi experienced liquefaction at a depth of 12-18 meters with a moderate to very high level.

Correlation of excess pore water pressure ratio on flow liquefaction phenomenon in Sibalaya – Central Sulawesi Province

On September 28, 2018, liquefaction in Sibalaya damaged irrigation canals and hit 51.2 hectares fields and roads. This phenomenon was triggered by an earthquake of magnitude 7.5 that shook Sigi Regency, Central Sulawesi Province. As an increase in soil pore water pressure is one of the causes of liquefaction, the pore water pressure ratio (ru) at the study site was analyzed. Then, this figure is used as a point of reference to determine the liquefaction potential. Standard Penetration Test (SPT) data and laboratory tests from four boreholes resulting from soil investigations in 2021 with a maximum depth of 20 meters were utilized in this study, along with microtremor data down to the depth of bedrock from test results in 2023. Based on the data, the liquefaction potential was assessed using the one-dimensional nonlinear site response approach, the GQ/H + PWP model, and the DEEPSOIL V.7 program. At multiple layers of boreholes, ru is more than or equal to 0.8, indicating that the Sibalaya liquefaction flow area is still susceptible to liquefaction.

Parametric Design and Field Behavior of Earthen Structures

The stability of earthen structures is governed by field uncertainties arising from material properties, environment loading, and slope geometry. This research devised a systematic approach to capture the effects of field uncertainties on the stability of natural and manmade slopes. New design charts were developed by incrementally changing slope geometry and randomly generating shear strength parameters. Subset simulation was used to determine the safe range of soil properties for various slopes. The charts were applied to three published case studies with distinct triggering mechanisms resulting from complex field settings. All of the investigated slopes were found to be stable (factor of safety (FOS) > 1.0) under the reported geometry and shear strength parameters while assuming no water table. The effects of soil properties’ variation and environmental conditions on fluctuating water table were captured through history matching. Results indicated three distinct failure mechanisms: foundation settlement of a glacial moraine till (Vernon, British Columbia) due to an increased pore water pressure during construction of the compacted fill (FOS = 1.45 without berms and 2.24 with berms); instability in the natural cut (FOS = 0.98) comprising layered glacio-lacustrine clays (Labret, Saskatchewan) due to saturation of the entire slope resulting from a long duration rainfall; and collapse of a compacted fill (FOS = 0.98) on a glacial moraine till (Hamelin Creek, Alberta) due to soil saturation arising from thawing of a frozen layer in the slope. This validation illustrates that the new approach fully captures environmental loading (resulting in water table variation in the slope) and partly captures construction practice and site geology via soil properties.

STRATA SUBSIDENCE CHARACTERISTICS OF SHIELD TUNNELING IN COASTAL SOFT SOIL AREA

In order to study the subsidence characteristics caused by large diameter shield tunneling in coastal soft soil area, based on the project of North Oujiang shield tunnel in Wenzhou City, the displacement field, seepage field and stress field of surrounding rock during shield tunnel construction process under fluid-solid coupling were analyzed by using finite difference method. The results show that when the shield tunneling passes through the monitoring section of the tunnel, the surrounding rock in a certain range of this section above the tunnel will be uplifted. Shield tail grouting can effectively control the settlement of the ground, and the increasing range of the ground subsidence gradually decreases. With the advance of the shield the pore water pressure increases, and the pore water pressure in the soil layer will rise sharply due to the shield tail grouting. When the shield passes through the monitoring section of the tunnel, the strata stress above the tunnel increases due to uplift extrusion, and the strata stress below the tunnel decreases due to stress releasing. When the grouting at the tail of the shield is completed and gradually moves away from the monitoring section, the stress releasing results in the decrease of the stress in the surrounding stratum and shows a funnel-shaped form.

EXPERIMENTAL STUDY OF FINE GRAIN CONTENT OF SOIL ON LIQUEFACTION POTENTIAL

One of the efforts to realize environmentally sound development is to pay attention to disaster aspects that threaten an area, one of which is the phenomenon of liquefaction. The liquefaction disaster is of particular concern after the 2018 Palu liquefaction, damaging and claiming many victims. Liquefaction is a phenomenon in soils that are initially solid and then turn liquid due to increased pore water pressure due to cyclic loads or earthquakes, which reduce the carrying capacity of the soil. Not all types of soil have the potential to experience liquefaction. In general, soils with a high liquefaction potential are soils with a high content of fine sand grains and fewer clay particles. This study aims to determine the effect of fine grain content (silt and clay) on the magnitude of the liquefaction potential. The study was conducted using experimental modeling with fine sand soil samples (passed sieve number 40 and retained sieve number 100), which varied the content of fine grains (passed sieve number 200) as much as 0%, 5%, 10%, 15%, and 20%. The results of this study indicated that soil with a fines content of 0% liquefied after 5.56 seconds, and soil with a fines content of 20% experienced liquefaction after 23.84 seconds. This condition shows that the higher fine content of soil decreases its liquefaction potential.

Wetting induced instabilities in layered slopes: A Material Point Method analysis

The increase of pore water pressure due to rainfall infiltration or upstream recharge is among the primary triggers of landslides, and soil layering has a significant effect on the hydromechanical behavior of the slope. The failure and post-failure behavior of heterogeneous layered slopes triggered by these phenomena are investigated in this study. In particular, a low permeability layer is embedded in a reference slope with different inclinations, and the impact of different saturation mechanisms on the post-failure behavior is assessed. To this aim, an unsaturated formulation of the Material Point Method (MPM) is used to reproduce the whole deformation process of a layered slope. The results show different failure and post-failure mechanisms and kinematics for both upstream recharge and rainfall infiltration (i.e., bottom-up and top-down saturation processes, respectively). Bottom-up saturation mechanism triggers deep failure mechanisms that barely evolve during the instability process. On the contrary, top-down saturation mechanism induces an anticipated shallow semi-planar failure limited by the location of the low permeable layer. These failures are characterized by high velocities and by a deepening of the slip surface during the post-failure process. Final displacements in both wetting mechanisms are of the same order of magnitude. The subsequent reactivation movements are observed as a result of the continuous injection of water in the system.

Analisis Potensi Likuifaksi Menggunakan Data CPT (Cone Penetration Test) di Teluk Bintuni Papua Barat

West Papua is an eastern part of Indonesia that has great potential for earthquakes. Eastern Indonesia's seismic activity was triggered by geographical conditions in three major earthquake paths, namely the zone of the confluence of the Pacific and Papua New Guinea plates, the Sorong fault line and the Tarera – Aiduna fault (Naryanto, 2019). Bintuni Bay is one of the regencies in West Papua Province, located between the south coast of Bird's Head and the coast of the Onin Peninsula, facing the Seram Sea off the west coast of Papua. The sorong fault is one of the active faults (faults) of the earthquake source in the Bintuni Bay area (Ciptakarya.pu, 2002). Liquefaction is one of the failures in the soil structure that can occur due to cyclic loads or earthquake vibrations. Liquefaction is the event of the transformation of noncohesive soil material from solid to liquid properties due to an increase in pore water pressure in the soil cavity. The liquefaction potential was analyzed using the boulanger Idriss method (2014). This method compares the value of CSR (Cyclic Stress Ratio) with CRR (Cyclic Resistance Ratio). The factor of safety value (FS) is used as a limit for potential liquefaction or not. If FS > 1 indicates that the soil layer has no potential for liquefaction, whereas if FS < 1 indicates a potential soil layer of liquefaction. The results of the analysis showed that the magnitude of ≥ 5,6 Mw with soil acceleration (amax) ≥ 0,16 g has the potential to reduce liquefaction with very low to very high categories. Coastal areas have a higher liquefaction potential than land areas.

Pervious Concrete Utilized as a Base Slab of Pavement Edge Drains

The drainage base plate is generally made of normal concrete. The application of pervious concrete as base-slab of pavement edge drain will then be possible to infiltrate storm water runoff on the pavement surface that is not infiltrated through the pavement surface. The edge drain does not only accommodate storm water flow, but also transmits water to the ground so that it can restore the ground water level or can be reused through a reservoir in the ground underneath. The effectiveness of the application of pervious concrete as a drainage base plate on silt-clay soils was conducted experimentally. The thickness of the porous concrete slab in the modeling box is 7 cm, laid above 20 cm height of silty clay soil layer. Reference soil conditions as well as contours and cross-sectional characteristics of the edge drain are taken based on the condition of one of the existing drainages in West Bandung. Based on the results of numerical simulations using Geostudio SEEP/W, it can be seen that there is an increase in pore water pressure in the area of the pervious concrete slab and the surrounding soil. The pore water pressure at the bottom of the plate is in the range of 18.64 kPa. Overall, the pore water pressure in the first modeling tends to be higher than in the second modeling. On the third day of testing, the difference in pore water pressure between the two modeling conditions is 27.08%.

Seismic Response of Utility Tunnels with Different Burial Depths at the Non-Homogeneous Liquefiable Site

Damage to underground structures induced by soil liquefaction under cyclic loads such as earthquakes has long been an important issue in underground engineering practice. In this paper, five models are developed using Flac3D software to analyze the effect of burial depth on the force, deformation characteristics, and uplift behavior of utility tunnels in the non-homogeneous site containing a liquefied layer. The cyclic shear property of saturated sand and the increase in pore water pressure during the earthquake are modeled using a cyclic load-volume strain increment model, using Shell-Type structural elements to model underground utility tunnels, and by using plastic hinges to represent the bending moment capacity of member’s joints. Numerical results show that for shallow-buried utility tunnels, increasing the burial depth increases the bending moment, shear force, and deformation of the structure while significantly reducing its uplift. Therefore, for high-strength shallow-buried utility tunnels, appropriate increase in burial depth can improve its seismic safety.

Rheological Behaviors and Damage Mechanism of Asphalt Binder under the Erosion of Dynamic Pore Water Pressure Environment.

Asphalt binder plays an important role in the overall resistance of asphalt mixture to the moisture damage induced by a dynamic pore water pressure environment. This study evaluates the moisture sensitivity of asphalt binder from the perspective of rheological behaviors using the dynamic shear rheometer (DSR) and the bending beam rheometer (BBR) methods at high, medium, and low temperatures. The damage mechanism is further discussed quantitatively based on the Fourier transform infrared spectroscopy (FTIR) method. The results indicate that a longer conditioning duration is beneficial for asphalt binder to recover its adhesion at 60 °C in multiple stress creep recover (MSCR) tests, but the increasing pore water pressure magnitude of 60 psi held an opposite effect in this study. The asphalt binder's fatigue life at 20 °C in linear amplitude sweep (LAS) tests decreased obviously with conditioning duration and environmental severity, but the reducing rate gradually slowed down, while the groups of 50 psi-4000 cycles and 60 psi-4000 cycles held a comparable erosion effect. Both the stiffness and relaxation moduli at -12 °C in the BBR tests exhibited an obvious decreasing trend with conditioning duration and environmental severity. The erosion effect on the asphalt binder was gradually enhanced, but it also exhibited a slightly more viscous performance. Water conditioning induced several obvious characteristic peaks in the FTIR absorbance spectra of the asphalt binder. The functional group indexes presented a trend of non-monotonic change with conditioning duration and environmental severity, which made the asphalt binder show complicated rheological behaviors, such as non-monotonic variations in performance and the abnormal improving effect induced by dynamic pore water pressure conditioning.