Journal of Measurements in Engineering

Journal of Measurements in Engineering, (in Press).Wei Li, Youcai Cao, Yuanhao Li, Quan Wang, Yali Wang, Jian Yang, Yiwei JiaoExpansive, collapsible saline soils – widespread across northwestern China – are especially susceptible to desiccation-driven shrinkage, which progressively degrades soil fabric and triggers structural damage. Here we evaluate whether water-soluble polyacrylamide (PAM) can simultaneously enhance water retention and mechanical integrity in such soils. Using Atterberg-limit characterisation, indirect tensile testing, disintegration assays and desiccation – shrinkage experiments, we show that increasing PAM concentration consistently raises the liquid limit and plasticity index, whereas the plastic limit remains largely unchanged. Both shrinkage resistance and tensile capacity exhibit a clear optimum at 0.8 % PAM, where the shrinkage limit is maximised and tensile strength reaches its peak. In agreement with these macroscopic gains, PAM substantially delays disintegration and prolongs the time to complete dispersion, indicating improved stability upon wetting. Throughout drying – spanning rapid, falling-rate and constant-rate evaporation regimes – PAM-treated soils lose water markedly more slowly, demonstrating a robust improvement in water-holding capacity. We attribute these enhancements to hydrogen bonding between amide functionalities and water molecules, polymer-chain entanglement that promotes interparticle bridging, and a reduction in particle-surface electrokinetic (zeta) potential that stabilises the soil fabric.

Journal of Measurements in Engineering, (in Press).Jianhua LiuTo enhance the convenience of measuring unbalanced vibrations in rotating equipment and meet the on-site operation and maintenance requirements, a portable vibration and dynamic balance measurement system was designed and tested. The system, with the STM32F407VGT6 chip as its core, mainly consists of data detection module, data processing and transmission module, and terminal control and display module. The data detection module includes photoelectric sensors and vibration sensors. The data processing and transmission module incorporates optocoupler isolation, A/D conversion, and multiple communication modules. The terminal control and display module enables human-computer interaction and remote management. In terms of hardware design, circuits such as tracking band-pass filters and programmable gain amplifiers were developed to optimize signal acquisition quality. At the software level, fundamental frequency extraction algorithms including DFT were integrated to ensure accurate extraction of vibration characteristics. Experimental verification shows that the system can achieve high-precision acquisition of vibration signals and calculation of unbalance within the rotational speed range of 0-3000 rpm. The coincidence degree of fundamental frequency extraction results between the STM32 hardware terminal and the MATLAB software terminal exceeds 95 %, and data interaction and remote monitoring can be accomplished through multiple communication methods. This system meets the requirements of on-site portable operation and maintenance, providing reliable technical support for dynamic balance correction of rotating machinery.

Journal of Measurements in Engineering, (in Press).Fangcai Zhu, Haijie Wen, Zengjie Liu, Jiang Guo, Xuebin XieTwo types of rock specimens simulating grout curtains were prepared: one featuring solely an axial through-hole and the other featuring combined axial and transverse holes (termed combined-hole specimens). Coupled permeability-damage tests under cyclic loading-unloading were conducted to analyze the effects of peak stress level, confining pressure, seepage pressure difference, and defect geometry (curtain filling configuration) on permeability evolution and damage accumulation. The results indicate that: (1) Peak stress level is the primary factor governing damage development rate; (2) Higher confining pressure mitigates damage in the surrounding rock and decelerates permeability increase; (3) Larger seepage pressure difference (≥ 0.5 MPa) significantly enhances the stability and accuracy of permeability measurements; (4) For combined-hole configurations, increasing the transverse hole area (and thus the grout volume) provides more lateral seepage paths, effectively reducing axial permeability by up to two orders of magnitude. This study provides an experimental framework for assessing the long-term sealing performance of grouted curtains under repeated dynamic loading akin to blasting disturbances.

Journal of Measurements in Engineering, (in Press).Yang Ma, Huimei Zhang, Yuli Ouyang, Yue ZhangThis article designs a small-scale farmland rainfall runoff sampler for collecting rainwater during runoff events and performing chemical analysis. The system automatically collects up to 24 samples simultaneously using an STM32 microcontroller as its control unit. The controller adjusts the PWM signal to manage a DC motor's rotation and on/off state, and it accurately positions the sampling bottles via guide slots and position sensors. When the sampling bottle is positioned, the collection end sends a signal to start the peristaltic pump, which delivers water to the receiving end. And The flow rate is measured by a turbine flowmeter equipped with a pulse recorder. After calibration, the error of each 500 ml sample can be controlled within ±2 %, demonstrating relatively high accuracy and making the sampler suitable for actual sampling requirements. Its simple structure also enhances the durability of equipment in complex outdoor environments. Implementing unmanned rainwater collection can save manpower and material costs while avoiding the danger and uncertainty of manual sampling in rainy weather. The cap of the sampling bottle is designed with anti-volatility features to prevent the volatilization of chemicals such as pesticides and fertilizers in the rainwater, which is beneficial for improving the accuracy of soil and water monitoring.

Journal of Measurements in Engineering, (in Press).Lijun Mao, Tianxiang Zhou, Chenghui NanThe increasing of forest fires highlights the importance of rapidly and accurately quantifying the burned areas, which is crucial evidence for determining the cause of fire and assigning responsibility. This study develops an operational tool based on the cloud-computing abilities of the PIE-Engine platform and Sentinel-2 satellite imagery. The burned areas are rapidly extracted by applying differential spectral indices such as dNDVI, dNBR and dNBR2 using the adaptive thresholds determined by the Otsu algorithm. Compared with field investigations, the accuracy of using a wildfire case in Liuhe Village, Hubei Province is high. The findings indicate that dNBR can achieve an area accuracy of 98.22 % and a pixel-level F1-score of 0.94, significantly higher than dNDVI. Although the accuracy of the random forest model is slightly high, the dNBR based method achieves an excellent balance between computational efficiency (about 2 s of processing time) and accuracy. In addition, we have developed a user-friendly web application that allows for custom parameter settings and visualizes results as a quantitative burned area map. This tool only requires a web browser, greatly reducing the technical barriers of remote sensing applications and providing a transparent, efficient, and accessible solution for supporting forest fire investigation and emergency response.