Transportation Geotechnics最新文献

Research and prediction of early-age loads in double-block ballastless track structure 双块式无砟轨道结构早期荷载的研究与预测

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2024-11-01 DOI: 10.1016/j.trgeo.2024.101426

Mengxuan Ye , Zhiping Zeng , Peicheng Li , Guoshun Chen , Roman Wan-Wendner

Considering the hydration reaction of cement, a finite element model(FEM) of the coupling of temperature and humidity field and chemical field in the early age of the double-block ballastless track structure was established, and a field monitoring test on the early age of track slab was carried out with the newly constructed Fuzhou-Xiamen high-speed railway line as a case to verify the correctness of the FEM. Based on the official meteorological data from China Meteorological Administration (CMA) and the FEM, the dataset of vertical temperature and humidity gradients in the early age of the track slab was constructed, and five machine learning training models, namely, machine learning (MLR), multivariate polynomial regression (MPR), support vector regression (SVR), random forest (RF), and gradient boosted regression (GBR), were adopted to train the temperature gradient model and humidity gradient model for the early age of the track slab. The research results show that: (1) under the combined effect of solar radiation, convective heat transfer, radiative heat exchange and the cement hydration reaction, the temperature loading leads to the susceptibility of the sleepers to diagonal cracking; the humidity loading leads to transverse cracking in the center region of the surface of the track slab; (2) the finite element model with a higher accuracy provided the training dataset for the machine learning model. According to the Spearman correlation coefficient, the input features of the temperature gradient model and the humidity gradient model are determined, respectively; (3) Five ML methods were used to train the temperature gradient model and humidity gradient model, both of which demonstrated good generalization ability with a coefficient of determination(R²) greater than 0.85. Among these methods, GBR and SVR exhibited the best performance; From the perspective of MAPE value, the prediction effect of the temperature gradient training model was better than that of the humidity gradient training model; (4) The curing method and the average value of the relative humidity were the important input features influencing the training models for the temperature and humidity gradient loads, respectively. This finding provided an important guideline for the construction of ballastless track structures.

考虑水泥水化反应，建立了双块式无砟轨道结构早期龄期温湿度场与化学场耦合的有限元模型，并以新建福州至厦门高速铁路为例，对轨道板早期龄期进行了现场监测试验，验证了有限元模型的正确性。基于中国气象局（CMA）的官方气象数据和 FEM，构建了轨道板早期龄期垂直温湿度梯度数据集，并建立了五种机器学习训练模型，即采用机器学习（MLR）、多元多项式回归（MPR）、支持向量回归（SVR）、随机森林（RF）和梯度提升回归（GBR）五种机器学习训练模型训练轨道板早期温度梯度模型和湿度梯度模型。研究结果表明(1）在太阳辐射、对流换热、辐射换热和水泥水化反应的共同作用下，温度荷载导致轨枕易产生斜向裂缝，湿度荷载导致轨道板表面中心区域产生横向裂缝；（2）精度较高的有限元模型为机器学习模型提供了训练数据集。根据斯皮尔曼相关系数，分别确定了温度梯度模型和湿度梯度模型的输入特征；（3）使用五种 ML 方法训练温度梯度模型和湿度梯度模型，这两种方法都表现出良好的泛化能力，判定系数（R2）均大于 0.85。从 MAPE 值来看，温度梯度训练模型的预测效果优于湿度梯度训练模型；（4）固化方式和相对湿度平均值分别是影响温度梯度和湿度梯度载荷训练模型的重要输入特征。这一发现为无砟轨道结构的建造提供了重要指导。

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引用次数: 0

Permanent deformation and particle crushability of calcareous sands under cyclic traffic-induced loadings through simple shear apparatus 通过简易剪切装置测量钙质砂在交通诱导循环载荷作用下的永久变形和颗粒破碎性

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2024-11-01 DOI: 10.1016/j.trgeo.2024.101428

Manouchehr Hejazi, Kazem Fakharian, Farzad Kaviani-Hamedani

This study focuses on investigating permanent deformations, encompassing normal and shear strains, of calcareous sandy soils subjected to drained cyclic traffic-induced loadings. The investigation utilizes a Simple Shear (SS) apparatus allowing for variations in both normal and shear stress components over each cycle and incorporates Principal Stress Rotation (PSR), a feature not replicable in conventional cyclic uniaxial triaxial tests which is the key aspect of this research. The study also accounts for the harmonically changing the effective horizontal stress resulting from cyclic variations of effective vertical stress, conducted under a horizontally constrained boundary condition with zero lateral strain. A series of drained cyclic simple shear experiments is carried out, implementing a heart-shaped stress path, encompassing up to 1000 cycles. The objective of the study is to analyze permanent normal and shear deformations, along with associated total particle crushing, using both sieving analyses and 2D image processing of particles. The study also evaluates the impact of an initial static shear stress originating from the longitudinal slope of roads. The findings highlight the influences of induced cyclic amplitudes of stress components, principal stress and strain rate rotation, and initial static shear stress on the development of permanent strains. Furthermore, the research characterizes particle crushability in terms of total crushability over such loading, examining its dependency on relative density and variations in both shear and normal stress components.

本研究的重点是调查钙质砂土在排水循环交通诱导荷载作用下的永久变形，包括法向应变和剪切应变。该研究采用了简易剪切（SS）设备，允许法向应力和剪切应力成分在每个循环中发生变化，并结合了主应力旋转（PSR），这是传统循环单轴三轴试验无法复制的特征，也是该研究的关键方面。这项研究还考虑了有效垂直应力周期性变化引起的有效水平应力的谐波变化，这种变化是在横向应变为零的水平约束边界条件下进行的。进行了一系列排水循环简单剪切实验，实施了心形应力路径，包括多达 1000 个循环。研究的目的是利用筛分分析和颗粒的二维图像处理，分析永久法向和剪切变形，以及相关的总颗粒破碎。研究还评估了道路纵坡产生的初始静态剪应力的影响。研究结果强调了应力分量的诱导循环振幅、主应力和应变率旋转以及初始静态剪切应力对永久应变发展的影响。此外，该研究还从这种加载情况下的总碾压性角度描述了颗粒的可碾压性，研究了其与相对密度以及剪应力和法向应力分量变化的关系。

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引用次数: 0

Effect of torsional shear stress on the deformation characteristics of clay under traffic load 交通荷载下扭转剪应力对粘土变形特性的影响

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2024-11-01 DOI: 10.1016/j.trgeo.2024.101413

Lin Guo , Yajing Meng , Zheng Wang , Hui Li , Feng Chen , Yilong Sun

The soft clay under the road ground will suffer cyclic torsional shear stress encountered traffic load in addition to axial stress, which will cause further deformation of clay. To investigate the effect of torsional shear stress on the cumulative axial strain of clay, a series of undrained tests under cardioid stress path were performed on K₀ consolidated undisturbed samples by using a hollow cylinder apparatus (HCA). The effect of vertical cyclic stress ratio (VCSR) and shear stress ratio (η) on the deformation and degradation characteristics of clay was investigated. The results indicate that there is inconsistency between the strain path and stress path. The increase in η further accelerates the accumulation of axial strain, which resulted from the degradation of clay induced by torsional shear stress. Considering the VCSR and η, a calculation method of degradation index was developed. Furthermore, a cumulative axial strain prediction model of clay under the cardioid stress path was established considering the degradation. This model addresses the limitation of traditional prediction models by considering the impact of torsional shear stress on cumulative axial strain.

路基下的软粘土除了轴向应力外，还将受到交通荷载的周期性扭转剪应力，这将导致粘土进一步变形。为了研究扭转剪应力对粘土累积轴向应变的影响，我们使用空心圆筒设备（HCA）对 K0 加固的未扰动样本进行了一系列心向应力路径下的排水试验。研究了垂直循环应力比（VCSR）和剪切应力比（η）对粘土变形和降解特性的影响。结果表明，应变路径和应力路径不一致。η的增加进一步加速了轴向应变的累积，而轴向应变的累积是由扭转剪应力引起的粘土降解造成的。考虑到 VCSR 和 η，开发了降解指数的计算方法。此外，考虑到降解，还建立了心形应力路径下粘土的累积轴向应变预测模型。该模型考虑了扭剪应力对累积轴向应变的影响，解决了传统预测模型的局限性。

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引用次数: 0

Predicting strain energy causing soil liquefaction 预测导致土壤液化的应变能

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2024-11-01 DOI: 10.1016/j.trgeo.2024.101419

Yanbing Liu , Hamed Javdanian , Ali Tahmasb

Liquefaction, which typically occurs in saturated sandy soil deposits, is one of the destructive phenomena that can occur during an earthquake. When the soil reaches liquefied state, it loses a significant amount of resistance and stiffness, which often results in widespread catastrophic damages. Therefore, accurate evaluating the potential of soil liquefaction occurrence is of great importance in earthquake geotechnical designs in regions prone to this phenomenon. The strain energy-based approach is a novel robustness technique to evaluate liquefaction potential. In the current research, 165 laboratory data sets from cyclic experiments were collected and analyzed. A predictive model using gene expression programming (GEP) was proposed to assess strain energy needed for occurrence of soil liquefaction. Assessing physical behavior of developed GEP-based model was conducted through sensitivity analysis. Performance of GEP-based was validated by comparing with a series of centrifuge experiments and cyclic triaxial tests results. Subsequently, after experimental verification of numerical modeling, the strain energy required for soil liquefaction under cyclic loading at different conditions were numerically evaluated and compared with the strain energy calculated by proposed model. Finally, the developed GEP-based model was compared with established strain energy-based relationships. The results indicated high precision of proposed GEP-based model in determination of strain energy required for soil liquefaction triggering.

液化通常发生在饱和的砂质土壤沉积中，是地震时可能出现的破坏现象之一。当土壤达到液化状态时，会失去大量的阻力和刚度，往往会造成大范围的灾难性破坏。因此，准确评估土壤液化发生的可能性对于易发生这种现象地区的地震岩土工程设计具有重要意义。基于应变能的方法是一种评估液化潜力的新型稳健性技术。在当前的研究中，收集并分析了 165 组实验室循环实验数据。利用基因表达编程（GEP）提出了一个预测模型，用于评估发生土壤液化所需的应变能。通过敏感性分析评估了基于 GEP 开发的模型的物理行为。通过与一系列离心实验和循环三轴试验结果进行比较，验证了基于 GEP 的模型的性能。随后，在对数值模型进行实验验证后，对不同条件下循环荷载下土壤液化所需的应变能进行了数值评估，并与所建模型计算出的应变能进行了比较。最后，将所开发的基于 GEP 的模型与已建立的基于应变能的关系进行了比较。结果表明，所提出的基于 GEP 的模型在确定引发土壤液化所需的应变能方面具有很高的精度。

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引用次数: 0

Explainable machine learning-based prediction model for dynamic resilient modulus of subgrade soils 基于机器学习的路基土动态弹性模量可解释预测模型

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2024-11-01 DOI: 10.1016/j.trgeo.2024.101415

Xiangyang Li , Wenjun Liu , Changjing Xu , Ning Liu , Shuaike Feng , Xin Zhang , Yanbin Li , Jianwen Hao

The dynamic resilient modulus (M_R) of a subgrade soil is a fundamental parameter for evaluating the dynamic stability and service resilience of subgrade fillers and structures, as well as an instrumental input for calculating the mechanical response and fatigue life of a pavement structure. To accurately and reasonably characterise the M_R of subgrade soils, machine learning (ML) models were established using the support vector machine, random forest, and extreme gradient boosting algorithms based on a large-scale dataset including 3533 records of M_R tests conducted on subgrade soils. Meanwhile, the weighted plasticity index (WPI), initial moisture content (w), dry unit weight (γ_d), confining stress (σ_c), deviator stress (σ_d), and numbers of freeze–thaw cycles (N_FT) were set as the input variables to predict the M_R using ML models, which considered the effects of wheel loads, physical properties and climate fluctuation on the subgrade soils during the service period. Subsequently, the Shapley additive explanations method was developed to explain the prediction model for the M_R of subgrade soils based on ML algorithms. The results quantitatively illustrated the explicit mapping relationship and internal influencing mechanism between the significant features of the influences and M_R of subgrade soils, which was consistent with prior experimental and physical cognition. In summary, the study findings provide meaningful guidelines for the structural design and life evaluation of pavement subgrade engineering.

路基土的动态弹性模量（MR）是评估路基填料和结构的动态稳定性和使用弹性的基本参数，也是计算路面结构的机械响应和疲劳寿命的工具输入。为了准确、合理地表征路基土的 MR，基于大规模数据集（包括 3533 条路基土 MR 测试记录），使用支持向量机、随机森林和极梯度提升算法建立了机器学习（ML）模型。同时，将加权塑性指数 (WPI)、初始含水量 (w)、干单位重量 (γd)、约束应力 (σc)、偏差应力 (σd)、冻融循环次数 (NFT) 设置为输入变量，使用 ML 模型预测 MR，其中考虑了使用期间轮载、物理特性和气候波动对路基土的影响。随后，开发了基于 ML 算法的 Shapley 加性解释方法来解释路基土的 MR 预测模型。结果定量说明了影响因素的显著特征与路基土的 MR 之间的明确映射关系和内在影响机理，这与之前的实验和物理认知是一致的。总之，研究结果为路面基层工程的结构设计和寿命评估提供了有意义的指导。

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引用次数: 0

Evaluation of the methods used for estimating the bearing capacity of stone columns 评估用于估算石柱承载能力的方法

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2024-11-01 DOI: 10.1016/j.trgeo.2024.101405

Mahmoud Ghazavi , Movahed Rouhani , Arman Khoshghalb

Stone columns have been utilized for several decades due to their ability to improve the mechanical behavior of weak and marginal soil deposits. Reducing the cost of a project necessitates accurate estimation of the stone column capacity. This paper considers the existing analytical methods for estimating the bearing capacity of stone columns and evaluates their prediction accuracy. For this purpose, the results of 36 full-scale field tests on footings supported by stone columns are considered, and the measured bearing capacities (Q_M) are compared with the estimated bearing capacity (Q_E) values computed from 15 analytical solutions predicting the stone column capacity. For this comparison, five statistical approaches are employed in order to evaluate these 15 methods and identify the level of their prediction accuracy. Finally, the methods are ranked by the degree of accuracy with which they can estimate the load capacity. The findings of this research help designers and decision makers to choose a more reliable design method when dealing with stone columns.

由于石柱能够改善薄弱和边缘土壤沉积的机械性能，几十年来石柱一直被广泛使用。要降低工程成本，就必须准确估算石柱的承载力。本文探讨了估算石柱承载力的现有分析方法，并对其预测精度进行了评估。为此，本文考虑了对石柱支撑的基脚进行的 36 次全面现场测试的结果，并将测得的承载力（QM）与根据 15 种预测石柱承载力的分析方法计算得出的估计承载力（QE）值进行了比较。为了进行比较，我们采用了五种统计方法来评估这 15 种方法，并确定其预测准确性的高低。最后，根据这些方法估算承载能力的准确程度对其进行排序。研究结果有助于设计人员和决策者在处理石柱时选择更可靠的设计方法。

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引用次数: 0

Variation of Secant Young’s Modulus in an Unsaturated Gap-Graded Granular Fill 非饱和间隙分级粒状填料中的秒杨氏模量变化

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2024-11-01 DOI: 10.1016/j.trgeo.2024.101416

Kai Liu , Wen-Bo Chen , Wei-Qiang Feng , Dao-Yuan Tan , Chao Zhou , Jian-Hua Yin

It is of great significance to understand the variation of stiffness in unsaturated granular materials for predicting performance of earth structures. Variation of secant Young’s modulus in an unsaturated gap-graded granular fill was investigated using unsaturated triaxial tests with local strain measurements in this work. Unlike the insignificant suction impact on shear strength in coarse-grained granular material, it seems that suction has greater effect on stiffness of the tested soil at small strain. Young’s modulus enhances as suction and net confining pressure rise since average skeleton stress increases and soil skeleton gets more stable by meniscus water. In addition, specimen at larger suction possesses greater degradation speed than that at lower ones. One equation was adopted to estimate Young’s modulus of soil. It shows that this equation may capture the variations of secant Young’s modulus of soil under different suctions and net confining pressures.

了解非饱和粒状材料的刚度变化对于预测土体结构的性能具有重要意义。本研究利用非饱和三轴试验和局部应变测量，研究了非饱和间隙级配颗粒填料中的秒杨氏模量变化。与吸力对粗颗粒材料剪切强度的影响微不足道不同，吸力在小应变时似乎对测试土的刚度影响更大。杨氏模量随着吸力和净约束压力的增加而增大，因为平均骨架应力增加，土壤骨架在半月板水的作用下变得更加稳定。此外，吸力较大的试样比吸力较小的试样具有更快的降解速度。采用一个方程来估算土壤的杨氏模量。结果表明，该方程可以捕捉不同吸力和净约束压力下土壤杨氏模量的变化。

引用次数: 0

Experimental study on the deformation behavior of soils under one-dimensional unloading 一维卸载下土壤变形行为的实验研究

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2024-11-01 DOI: 10.1016/j.trgeo.2024.101432

Taishan Lu , Zan Li , Songyu Liu , Guojun Cai , Kai Wu , Wei Duan

Soils are usually subjected to one-dimensional unloading due to the excavation, groundwater recharge, and other activities. This paper investigates the deformation behavior of soils under one-dimensional unloading. A series of oedometer tests with loading–unloading cycles were conducted on silty sand, silt, silty clay, and muddy silty clay samples extracted from southern Jiangsu, China. The influence of effective vertical stress before unloading on rebound deformation of soils was investigated. Test results show that the unloading deformation of soils increases nonlinearly with the increasing unloading ratio. When the unloading ratio reaches 0.8, only 30% of the total rebound deformation occurs. The rebound ratio increases with the increasing effective vertical stress before unloading. A power function was proposed to describe the relationship between one-dimensional unloading modulus and unloading ratio with two parameters named initial one-dimensional unloading modulus and decrease rate of the one-dimensional unloading modulus. The initial unloading modulus increased linearly with the increase of effective vertical stress before unloading, and a power function could be used to describe the relationship between the decrease rate and effective vertical stress. Formulas were also proposed to predict the initial unloading modulus and decrease rate of the one-dimensional unloading modulus based on piezocone test measurements.

由于挖掘、地下水补给等活动，土壤通常会受到一维卸荷。本文研究了土壤在一维卸载下的变形行为。对从中国江苏南部提取的淤泥质砂、淤泥、淤泥质粘土和泥质淤泥质粘土样品进行了一系列加载-卸载循环的土力计试验。研究了卸载前有效垂直应力对土壤回弹变形的影响。试验结果表明，随着卸载率的增加，土壤的卸载变形呈非线性增加。当卸载率达到 0.8 时，仅发生总回弹变形的 30%。反弹率随着卸载前有效垂直应力的增加而增加。提出了一个幂函数来描述一维卸载模量与卸载率之间的关系，该函数有两个参数，分别为初始一维卸载模量和一维卸载模量下降率。初始卸载模量随卸载前有效垂直应力的增加而线性增加，可用幂函数来描述下降率与有效垂直应力之间的关系。此外，还提出了一些公式来预测基于压水试验测量的初始卸荷模量和一维卸荷模量的下降率。

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引用次数: 0

Experimental investigation on the temperature-dependent shear strength of frozen coarse-grained soil-rock interfaces by considering three-dimensional roughness 通过考虑三维粗糙度对冻结粗粒土-岩石界面随温度变化的剪切强度进行实验研究

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2024-11-01 DOI: 10.1016/j.trgeo.2024.101434

Yonglong Yang , Shibing Huang , Shuyang Yu , Haowei Cai , Jiawei Zhai

Climate warming has led to landslides, especially the slopes containing soil-rock interfaces. A series of shear tests were conducted on the coarse-grained soil (CGS) rock interface at low temperatures. The interface shear strength comprises the pre-peak bonding strength produced by ice and post-peak residual strength created by friction between the CGS and rock surface. As the temperature rose from -15 to -1 ℃, the bonded ice strength at different rough interfaces rapidly decreased by a maximum of 82.99 %, because more than 21.29 % of the pore ice had thawed within the CGS. However, the average interface residual strength had decreased by only 18.56 %, which is consistent with the variation of the internal friction angle of the frozen CGS. The interfacial shear strength was much lower than the shear strength of the frozen CGS below -1 ℃ and that the shear slide typically occurred at the interface. In addition, as the freezing temperature increased, the impact of the three-dimensional roughness to the interfacial shear strength decreased, because the warm frozen CGS could easily shear rupture and adhere to the interface, reducing the influence of the roughness. Finally, it was demonstrated that the Mohr-Coulomb failure criterion could be employed to predict the interface peak shear strength for different normal stresses. This study aims to determine the mechanism responsible for shear strength reduction at a frozen CGS-rock interface during warming and to provide some references for preventing landslides caused by rising temperatures.

气候变暖导致山体滑坡，尤其是含有土壤-岩石界面的斜坡。在低温条件下，对粗粒土（CGS）岩石界面进行了一系列剪切试验。界面剪切强度包括冰产生的前峰值粘结强度和 CGS 与岩石表面摩擦产生的后峰值残余强度。当温度从-15 ℃升至-1 ℃时，不同粗糙界面上的粘结冰强度迅速下降，最大降幅达 82.99%，因为超过 21.29% 的孔隙冰已在 CGS 内解冻。然而，平均界面残余强度仅降低了 18.56%，这与冻结 CGS 内部摩擦角的变化一致。界面剪切强度远低于-1 ℃以下冻结 CGS 的剪切强度，剪切滑动通常发生在界面上。此外，随着冷冻温度的升高，三维粗糙度对界面剪切强度的影响减小，因为温冻 CGS 很容易剪切断裂并粘附在界面上，从而减小了粗糙度的影响。最后，研究表明，莫尔-库仑失效准则可用于预测不同法向应力下的界面峰值剪切强度。本研究旨在确定气候变暖时冻结的 CGS 岩石界面剪切强度降低的机理，并为防止气温升高引起的山体滑坡提供一些参考。

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引用次数: 0

Performance of the polyurethane foam injection technique for road maintenance applications 用于道路养护的聚氨酯泡沫注射技术的性能

IF 4.9 2区工程技术 Q1 ENGINEERING, CIVIL

Transportation Geotechnics

Pub Date : 2024-11-01 DOI: 10.1016/j.trgeo.2024.101411

Aroondet Boonsung , Veena Phunpeng , Suksun Horpibulsuk , Atthapan Pathompongpairoj , Apiwich Sawatwutichaikul , Punvalai Choenklang , Menglim Hoy , Artit Udomchai , Arul Arulrajah

Road infrastructure plays an important role in strengthening transportation and driving the economic advancement of countries. However, the increasing traffic volume has accelerated road deterioration, particularly at critical points like bridge-road junctions. Traditional repair methods involving demolition and reconstruction lead to extended closures and high costs. This study explores the polyurethane (PU) foam injection technique as an alternative solution, which can reduce both repair time and costs. The research evaluates the application of PU foam in various road projects across Thailand, highlighting its ability to repair pavement surfaces and structures, even in severely damaged areas. Despite its advantages, the use of PU foam faces challenges due to a lack of standardized quality control. This paper proposes a set of working guidelines for PU foam injection, aimed at key stakeholders such as the Department of Highways, the Department of Rural Roads, and the Department of Local Administration. The findings underline the importance of establishing standardized methods to ensure the long-term effectiveness of PU foam in road maintenance. Future research should focus on refining these guidelines for diverse road conditions to support the sustainable development of national transportation infrastructure.

道路基础设施在加强交通和推动国家经济发展方面发挥着重要作用。然而，日益增长的交通量加速了道路的老化，尤其是在桥梁与道路交界处等关键位置。传统的维修方法包括拆除和重建，导致长时间的封闭和高昂的成本。本研究探讨了聚氨酯（PU）泡沫注射技术，将其作为一种可缩短维修时间并降低成本的替代解决方案。研究评估了聚氨酯泡沫在泰国各种道路项目中的应用，强调了其修复路面表面和结构的能力，即使是在受损严重的地区。尽管聚氨酯泡沫具有诸多优势，但由于缺乏标准化的质量控制，其使用仍面临挑战。本文针对公路部、农村道路部和地方行政部等主要利益相关方，提出了一套聚氨酯泡沫注入工作指南。研究结果强调了建立标准化方法的重要性，以确保聚氨酯泡沫在道路养护中的长期有效性。未来的研究应侧重于针对不同的道路条件完善这些准则，以支持国家交通基础设施的可持续发展。

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引用次数: 0