Xiaqing Qian
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Xiaqing Qian has a total of 10 co-authors. Here are the top co-authors by number of shared publications:
- Peng Zhang
School of Transportation Engineering, Nanjing Tech University, Nanjing 211816, China
3 shared publications - Shuangfeng Guo
College of Transportation Engineering, Nanjing Tech University, Nanjing 211816, China
2 shared publications - Bikai Wang
College of Transportation Engineering, Nanjing Tech University, Nanjing 211816, China
1 shared publication - Jiejun Yuan
State Grid Jiangsu Electric Power Co., Ltd., Nanjing 210000, China
1 shared publication - Jin Xia
Nanjing Metro Construction Co., Ltd., Nanjing 210024, China
1 shared publication - Kai Wu
Jiangsu Power Transmission & Transformation Company, Nanjing 210028, China
1 shared publication
Latest Publications
- Open Access
IoT Monitoring and Evaluating System for the Construction Quality of Foundation Pile
The quality of foundation pile is greatly influenced by human factors, and quality assessment is delayed. This paper introduces a new evaluation system based on Internet of Things (IoT) monitoring data of the foundation pile construction process. First, an IoT monitoring system of foundation pile construction process quality is established to monitor the key parameters for quality control in the foundation pile construction process, such as pile length, position, verticality, water–cement ratio, grouting volume, drilling/lifting speed, etc. Next, the absolute gray relational degree analysis method and the analytic hierarchy process (AHP) entropy-weighted combination weighting method are used to divide the monitoring data into different levels and determine the weight coefficients for quality indicators during foundation pile construction. Last, the IoT monitoring and evaluation system of the foundation piles construction process quality is applied to engineering. The results indicate that the monitoring system is convenient and efficient, and the quality evaluation method is reliable. The construction process quality of cement-mixing piles is rated as excellent. The construction process quality of bored piles Z0103 and Z0232 is excellent, and pile Z0012 is qualified.
Open AccessIoT Monitoring and Evaluating System for the Construction Quality of Foundation Pile
The quality of foundation pile is greatly influenced by human factors, and quality assessment is delayed. This paper introduces a new evaluation system based on Internet of Things (IoT) monitoring data of the foundation pile construction process. First, an IoT monitoring system of foundation pile construction process quality is established to monitor the key parameters for quality control in the foundation pile construction process, such as pile length, position, verticality, water–cement ratio, grouting volume, drilling/lifting speed, etc. Next, the absolute gray relational degree analysis method and the analytic hierarchy process (AHP) entropy-weighted combination weighting method are used to divide the monitoring data into different levels and determine the weight coefficients for quality indicators during foundation pile construction. Last, the IoT monitoring and evaluation system of the foundation piles construction process quality is applied to engineering. The results indicate that the monitoring system is convenient and efficient, and the quality evaluation method is reliable. The construction process quality of cement-mixing piles is rated as excellent. The construction process quality of bored piles Z0103 and Z0232 is excellent, and pile Z0012 is qualified.
- Open Access
- 27 June 2023
- Published by MDPI AG in Remote Sensing
- Vol. 15 (13) , 3298
A New Method for Continuous Track Monitoring in Regions of Differential Land Subsidence Rate Using the Integration of PS-InSAR and SBAS-InSAR
It is difficult for single time-series Interferometric Synthetic Aperture Radar (InSAR) processing to guarantee the accuracy and efficiency of continuous track monitoring in regions of differential subsidence. This paper proposes a new method, integrating the Persistent Scatterer InSAR (PS-InSAR) with high precision and the Small Baseline Subset InSAR (SBAS-InSAR) with high efficiency for continuous track monitoring in regions of differential land subsidence rates. Based on PS-InSAR processing, the Iterative Self-Organizing Data Analysis Techniques (ISODATA) algorithm is adopted to search the boundary of differential subsidence between slow and fast subsidence rates. The SBAS-InSAR processing with high frequency is used to continuously track and monitor the regions with fast subsidence rates incorporating original data and newly added data into small data sets from time to time according to SAR data updating, the monitoring results of which are obtained from the weighted average of the added results of SBAS-InSAR processing and the original results of PS-InSAR processing. The impact of SAR data updating on the slow subsidence rate region is so weak that it is not necessary to simultaneously update the corresponding monitoring results to improve global efficiency. If the slow subsidence rates region must be remeasured in relation to its previous subsidence, or the proportion of new data capacity alters compared with the original data set, PS-InSAR processing is used to analyze the whole monitoring region again using the complete data set. A case study performed on the west region of the Qinhuai River in Nanjing, China, indicates that the density of monitoring points in the fast-subsidence region is greatly improved, increasing from 711 points/km to 2760 points/km—an increase of 288.2%.- 27 June 2023
- Published by MDPI AG in Remote Sensing
- Vol. 15 (13) , 3298
Open AccessA New Method for Continuous Track Monitoring in Regions of Differential Land Subsidence Rate Using the Integration of PS-InSAR and SBAS-InSAR
It is difficult for single time-series Interferometric Synthetic Aperture Radar (InSAR) processing to guarantee the accuracy and efficiency of continuous track monitoring in regions of differential subsidence. This paper proposes a new method, integrating the Persistent Scatterer InSAR (PS-InSAR) with high precision and the Small Baseline Subset InSAR (SBAS-InSAR) with high efficiency for continuous track monitoring in regions of differential land subsidence rates. Based on PS-InSAR processing, the Iterative Self-Organizing Data Analysis Techniques (ISODATA) algorithm is adopted to search the boundary of differential subsidence between slow and fast subsidence rates. The SBAS-InSAR processing with high frequency is used to continuously track and monitor the regions with fast subsidence rates incorporating original data and newly added data into small data sets from time to time according to SAR data updating, the monitoring results of which are obtained from the weighted average of the added results of SBAS-InSAR processing and the original results of PS-InSAR processing. The impact of SAR data updating on the slow subsidence rate region is so weak that it is not necessary to simultaneously update the corresponding monitoring results to improve global efficiency. If the slow subsidence rates region must be remeasured in relation to its previous subsidence, or the proportion of new data capacity alters compared with the original data set, PS-InSAR processing is used to analyze the whole monitoring region again using the complete data set. A case study performed on the west region of the Qinhuai River in Nanjing, China, indicates that the density of monitoring points in the fast-subsidence region is greatly improved, increasing from 711 points/km to 2760 points/km—an increase of 288.2%. - Open Access
- 8 December 2022
- Published by MDPI AG in Applied Sciences
- Vol. 12 (24) , 12586
Grouting Additives and Information-Based Construction of Jet Grouting in the Water-Rich Sand Stratum
The dynamic action of groundwater in the water-rich sand stratum carries away injected cement slurry before it becomes solidified, which seriously affects the determination of the diameter and strength of the column. Grouting additives and information-based construction are two main actions to control the quality of jet grouting construction. This study introduced a solution of grouting additives and information-based construction of jet grouting in the water-rich sand stratum. First, high-polymer cement grout (HPCG), red mud and phosphogypsum cement grout (RPCG) and metakaolin cement grout (MKCG) additives were screened with a series of laboratory tests on solidification time and permeability; moreover, the mix proportion of grouting fluids was developed in order to adapt for water-rich sand strata. Secondly, information-based construction of jet grouting was conducted to control grouting quantity with real-time monitoring of drill rotational velocity, drill lifting speed and injection pressure equipped with the monitoring system on the double fluid jet grouting systems. Lastly, the validity of grouting additives and information-based construction in the water-rich sand stratum was verified via a test pile in situ, and a series of material tests on drilling core samples on permeability with SEM observation. The results indicate that the high polymer is the preferred additive of grouting fluids because the solidification time can be controlled in the range of 10 min to 20 min; the permeability of drilling core samples can reach the order of 10−7, with the mix proportion being A:B = 2:1, high-polymer additive:water > 1:3, with a water-cement ratio of 0.8. The specifications of information-based construction are a drill rotational velocity of 10 r/min, a drill lifting speed of 0.2 m/min, an injection pressure of 20 MPa and a grouting quantity of 40 L/min.
- 8 December 2022
- Published by MDPI AG in Applied Sciences
- Vol. 12 (24) , 12586
Open AccessGrouting Additives and Information-Based Construction of Jet Grouting in the Water-Rich Sand Stratum
The dynamic action of groundwater in the water-rich sand stratum carries away injected cement slurry before it becomes solidified, which seriously affects the determination of the diameter and strength of the column. Grouting additives and information-based construction are two main actions to control the quality of jet grouting construction. This study introduced a solution of grouting additives and information-based construction of jet grouting in the water-rich sand stratum. First, high-polymer cement grout (HPCG), red mud and phosphogypsum cement grout (RPCG) and metakaolin cement grout (MKCG) additives were screened with a series of laboratory tests on solidification time and permeability; moreover, the mix proportion of grouting fluids was developed in order to adapt for water-rich sand strata. Secondly, information-based construction of jet grouting was conducted to control grouting quantity with real-time monitoring of drill rotational velocity, drill lifting speed and injection pressure equipped with the monitoring system on the double fluid jet grouting systems. Lastly, the validity of grouting additives and information-based construction in the water-rich sand stratum was verified via a test pile in situ, and a series of material tests on drilling core samples on permeability with SEM observation. The results indicate that the high polymer is the preferred additive of grouting fluids because the solidification time can be controlled in the range of 10 min to 20 min; the permeability of drilling core samples can reach the order of 10−7, with the mix proportion being A:B = 2:1, high-polymer additive:water > 1:3, with a water-cement ratio of 0.8. The specifications of information-based construction are a drill rotational velocity of 10 r/min, a drill lifting speed of 0.2 m/min, an injection pressure of 20 MPa and a grouting quantity of 40 L/min.