Underground Construction Projects Research Articles

Leakage Analysis and Hazardous Boundary Determination of Buried Gas Pipeline Considering Underground Adjacent Confined Space

Urban underground construction projects are intertwined vertically and horizontally, and adjacent confined spaces such as water supply and drainage pipelines, side ditches and underground canals may exist near buried gas pipelines. Once the buried gas pipeline leaks, the gas will diffuse into the confined space through the soil and even enter the residential room by the confined space, which brings serious potential safety hazards. In this paper, the underground adjacent confined space hazardous boundary (HB) of underground gas pipeline leakage was defined, the distribution properties of gas leakage diffusion flow field were analyzed by numerical simulation and the distribution law of gas entering the confined space was studied. Using the least-squares method and multiple regression theory, the gas concentration prediction model in the adjacent confined space of buried gas pipeline leakage was established, the HB calculation model was further deduced, and the HB drawing board was drawn. The results showed that in the initial stages, the internal and external pressure and velocity distribution of the pipeline near the leakage hole were unstable, reaching a stable state after 60 s, and then the reverse flow occurred in the pipeline downstream of the leak hole. Reducing the minimum construction distance between the buried gas pipeline and the confined space improved the gas distribution concentration in the confined space. When the minimum construction distance increased from 3 m to 9 m, the gas concentration distribution decreased from 90.21% to 0.88%. Meanwhile, increasing the pipeline pressure and leakage diameter enhanced the gas concentration distribution in the confined space. The HB calculation model and HB drawing board realize the rapid determination of the HB between buried gas pipeline and confined space and offer a more reasonable basis for the design of gas pipeline safe distance in urban underground engineering construction.

Reduction of Carbon Emission Is Optimized During the Life Cycle of Commonly Used Force Main Pipe Materials

With increasing attention to global warming and greenhouse gas (GHG) emissions and providing a better environment for coming generations, there is a critical need to quantify and decrease the environmental impact. Underground construction projects are one of the biggest constructions in North America; consequently, it is one of the GHG emissions' primary sources. This research focused on optimizing the carbon dioxide (CO2) emissions for a 91 cm (36 in) diameter sewer pressure pipe with 3 m (10 ft) depth and 30 m (100 ft) length, operating at 690 kPa (100 psi) during the commonly used pipeline materials' life cycle: Cured-in-Place Pipe (CIPP), Pre-stressed Concrete Cylinder Pipe (PCCP), High-density polyethylene (HDPE) pipe, and Polyvinyl Chloride (PVC) pipe. The life operations for this study were considered 100-years. The four phases of a pipeline life cycle included in this study are fabrication, installation, operation, and disposal phases. Life cycle assessment (LCA) is a methodology to evaluate the environmental impacts of products or service systems throughout the complete life cycle from the cradle to the grave. The study results show that the CO2 emissions have been reduced by 16% on the PCCP pipe, 4% on PVC pipe, 1% on HDEP pipe, and by 3.2% and 2.0% on CIPP lining (50 years and 100 years life expectancy, respectively). It is recommended that field studies be conducted in future research to obtain the necessary data to overcome the dependence on assumptions made in this study. Also, I recommended including the direct and social costs, which will make the decision easier for engineers and decision-makers to choose the right choice.

Evaluating the Application of Rock Breakage without Explosives in Underground Construction—A Critical Review of Chemical Demolition Agents

The method of drilling and blasting with explosives is widely used in rock fragmentation applications in underground construction projects, such as tunnels and caverns. However, the use of explosives is associated with rigorous safety and environmental constraints, since blasting creates toxic fumes, ground vibrations, and dust. Because of these constraints, there has been a growing interest in transitioning away from explosives-based rock fragmentation. The use of explosives-free methods could lead to continuous operation by eliminating the need for idle time with additional ventilation required to exhaust the blast fumes. This paper first presents a critical review of various methods that have been developed so far for rock fragmentation without explosives. Such methods include thermal fragmentation, plasma blasting, controlled foam injection, radial-axial splitter, and supercritical carbon dioxide. Thermal fragmentation, as the name implies, uses high heat to spall high-grade ore. However, it requires high heat energy, which requires additional ventilation as compared to normal conditions to cool the work area. Plasma blasting uses a high temperature and pressure plasma to fracture rock in a safe manner. While this method may be environmentally friendly, its usage may significantly slow tunnel development due to the need to haul one or more large energy capacitor banks into and out of the work area repeatedly. Controlled foam injection is another chemical method, whereby foam is the medium for fracturing. Although claimed to be environmentally friendly, it may still pose safety risks such as air blast or flyrock due to its dynamic nature. A radial-axial splitter (RASP) is an instrument specially designed to fracture a borehole in the rock face but only at the pace of one hole at a time. Supercritical carbon dioxide is used with the equipment designed to provide a high-pressure jet stream to fracture rock, and replaces water in these instruments. The method of soundless chemical demolition agents (SCDA) is evaluated in more detail and its merits over others are highlighted, making it a potentially viable alternative to blasting with explosives in underground excavation applications. Future work involves the optimization of SCDA for implementation in underground mines. The discussion compares the key features and limitations, and future work needs are underlined.

Successfully managing Covid-19 on tunnelling operations for the Thames Tideway Tunnel, UK

The Covid-19 pandemic had a huge impact on the way the UK population lived and worked during 2020. This paper explores the challenges faced while boring the west section of the Thames Tideway Tunnel in London, UK, with particular focus on the first national lockdown that began in March 2020. It discusses how the reduction in personnel triggered closure of the site, the technical challenge of safely stopping a tunnel boring machine for extended periods of time and the practical difficulties of creating a Covid-safe environment in a challenging space. This case study can be used to inform other underground construction projects coping with coronavirus.

Prediction of Subsidence during TBM Operation in Mixed-Face Ground Conditions from Realtime Monitoring Data

The prediction of settlement during tunneling presents multiple challenges, as such settlement is governed by not only the local geology but also construction methods and practices, such as tunnel boring machine (TBM). To avoid undesirable settlement, engineers must predict the settlement under given conditions. The widely used methods are analytical solutions, empirical solutions, and numerical solutions. Analytical or empirical solutions, however, have limitations, which cannot incorporate the major causes of subsidence, such as unexpected geological conditions and TBM operational issues, among which cutterhead pressure and thrust force-related factors are the most influential. In settlement prediction, to utilize the machine data of TBM, two phases of long short-term memory (LSTM) models are devised. The first LSTM model is designed to capture the features affecting surface settlement. The second model is for the prediction of subsidence against the extracted features. One thing to note is that predicted subsidence is the evolution of settlement along TBM drive rather than its maximum value. The proposed deep-learning models are capable of predicting the subsidence of training and test sets with excellent accuracy, anticipating that it could be an effective tool for real-world tunneling and other underground construction projects.

Research on the Preparation of Microbial Capsules by Epoxy Resin-Coated Bacillus pasteurii

With the increasing number of underground engineering construction projects such as coal mining, tunnel, and subway, water inrush disasters occur more and more frequently. Inspired by the phenomenon of microbial mineralization and diagenesis, microbial-induced calcium carbonate precipitation (MICP) is used to repair cracks in cement-based materials, which provides a new idea to solve the problem of water inrush. To investigate the self-healing properties of microbial capsules, this paper selected epoxy resin E-51 cured by DMP-30 as the wall material and Bacillus pasteurii as the core materials for experiments. In this paper, a single-factor method was adopted to determine the optimal preparation process of microbial capsules and the oil-phase separation method to prepare the microbial capsules. The effects of various factors on the experimental results under different core-wall ratios, reaction time, reaction temperatures, and agitation rates were analyzed. Microbial capsules were analyzed by Fourier transform infrared spectroscopy and optical microscopy to explore the functional groups and features of microbial capsules. The experimental results showed that the microbial capsules achieved the best performance with a core-to-wall ratio of 1 : 3, a reaction temperature of 50°C, a reaction time of 40 min, and a stirring rate of 300 rpm. Meanwhile, we determined the spore survival rate of microbial capsules and finally studied the waterproofness, storage stability, and rupture under the pressure of microbial capsules. We concluded that microbial capsules have high-efficiency and self-healing properties.

Multi-LOD BIM for underground metro station: Interoperability and design-to-design enhancement

Underground metro stations as essential large-scale infrastructures that ease the traffic congestion on the overcrowded urban surface should be thoroughly designed, constructed and maintained. Building information modelling (BIM) has been increasingly employed for project design authoring, construction monitoring and operation management to promote digital engineering. Geotechnical design engaging numerical modelling techniques is an indispensable process for underground construction projects. These cross-disciplinary processes employing heterogeneous applications are yet to be coordinated in an efficient way, and thus improved interoperability can streamline the processes and optimise engineering design. This paper proposes an extension to the primary standard for openBIM data exchange – the Industry Foundation Classes (IFC) to facilitate wider adoption of BIM in underground infrastructure design, construction and management. Then a multiple level-of-detail (LOD) metro station BIM model is introduced to represent information at distinct levels of geometric and semantic richness required for varying application scenarios. Finally, we suggest a workflow underpinned by heuristic techniques, as an intermediate solution, to enhance the interoperability between a BIM authoring tool and a numerical modelling program for geotechnical analysis, and exemplify the workflow with the State Library Station of Melbourne. The proposed workflow offers an automated error-free, design-to-design solution, and hence enables the efficient exploration of design scenarios and construction optimisation before IFC is adopted by geotechnical modelling software.

Detection of karst voids at pile foundation by full-waveform inversion of single borehole sonic data

Drilled boreholes are commonly used to detect rock voids and fractures in underground construction projects such as pile foundations, tunnel borings, and other near surface human activities. However, voids can be missed by direct drilling due to their limited size. Borehole sonic sounding can be used to image voids in the vicinity of the borehole. We developed a new time domain full-waveform inversion method for borehole sounding data. The FWI method employ an amplitude envelope-based objective function which captures low-frequency components to provide the initial velocity model for further inversion. Then a global correlation-based objective function is applied for FWI based on the updated initial velocity model. Numerical studies show that modeled anomalies of a single void, multiple voids and fractures are successfully delineated by the inverted Vs velocity profile. The FWI method was applied to field data from a bridge foundation project in a karst area and compared to complementary cross-hole acoustic tomography borehole profiles and drilled corehole data. The single borehole FWI inverted velocity profiles identify voids in agreement with the cross hole tomography and corehole observations. The results demonstrate that FWI is capable of imaging karst voids near drilling boreholes using borehole sonic data.

Highly specialized geophysical methods for undergroud construction works – Semmering Base Tunnel, a practice report

AbstractThe use of geophysical methods for the planning of complex underground structures such as deep tunnels has made significant progress in the last two decades. The realization of large underground construction projects in complex geological environments has led to an increase of geophysical exploration during excavation activities, drilling, and geological documentation. The aim is to continuously update and improve the geological model in order to identify and mitigate potential risks. Flexible planning of geophysical measurements and their fast and efficient implementation are required to minimize the impact on ongoing construction works.During construction of the Semmering Base Tunnel geophysical measurements were and are used to supplement exploratory drillings and tunnel documentation. This paper presents results from the construction lots SBT1.1 (Gloggnitz) and SBT3.1 (Grautschenhof) with an emphasis on carbonate prediction, and from the Göstritz cavern where sudden water ingress required an update of the geologic model. For each assignment a tailored‐made geophysical methodology was designed and applied.

A case study on the design, numerical modelling and preliminary testing of tension piles in weak rock

Over the last twenty years several major tunnel projects have been constructed in the Copenhagen area in the Danian limestone, either in the Copenhagen Limestone or in the Bryozoan limestone; in parallel, developments have been made in the characterization of these rocks. The Danian limestones are weak sedimentary rocks with highly variable properties in terms of their strength, stiffness and in their mass permeability. Their properties are governed by their genesis resulting in a large variation in the carbonate content, their induration and a large variability of the fissuring and distribution of fissuring. The paper describes the experience gained from selected underground construction projects in the Copenhagen area, specifically for the passive uplift anchors/tension piles that are often uses as a means to resist uplift forces resulting from the porewater pressure exerted at the underside of the base slab of major underground structures. While tension piles are common in Copenhagen, as they are often used for basement construction too, the authors are not aware of a documented calculation method. The paper presents a summary of the case histories published for ground anchors in Danian limestone and proposes a calculation method for the unit shaft resistance of small diameter tension piles as well as the comparison with numerical modelling and preliminary testing undertaken for the Sydhavn metro in Copenhagen.

Research on Grouting Materials for Underground Construction Projects

The engineering practice shows that the application of grouting technology to treat underground engineering has strong applicability and is one of the most commonly used technical means at present. Based on the underground engineering, this paper introduces the research achievements of grouting materials in recent years, including cement-based grouting materials, mixed grouting materials, anti-scouring grouting materials, and ultra-fine cement grouting materials. Current demand of grouting materials in underground engineering, there exists large dosage of cement, high content, high cost, serious environmental pollution problems, such as looking for alternatives or mixed with other raw materials for preparation of cementation material become the development trend, compared with the cement grouting material, chemical grouting material with higher performance, but in smaller projects within the scope of application. How to reduce the production cost of chemical grouting materials, simplify the production process, overcome the existing toxicity, reduce environmental pollution and improve the durability of solidified body has become the bottleneck of its popularization and application. Some achievements have been made in the modification of cement or chemical materials by nanometer components, but there is still a long way to go before the large-scale application of grouting engineering.

Demonstration and Analysis of Urban Traffic Tunnel Expansion Project Adjacent to Buildings

With the increasing number of urban underground construction projects, the evaluation of the influence of tunnel expansion on building foundation is one of the important factors to be considered in the project. In this paper, the deformation of the upper structure and the deformation pattern of the upper structure were analyzed, and the two-dimensional finite element model was built based on the case of Chongqing Jiefangbei Underground Ring Road Expansion Project Scheme. Comparative analysis of the deformation and changes in stress of the two tunnel expansion construction schemes of full-frame support and bolt suspension was performed, and the safety, rationality and feasibility of the bolt suspension scheme was confirmed through project safety analysis. It is hoped that this paper will serve as a reference for similar projects in the safety control technology of tunnel construction process.

Investigation of the health effects on workers exposed to respirable crystalline silica during outdoor and underground construction projects.

Chronic exposure of workers to powder containing crystalline silica (Silicon dioxide; SiO2) can lead to chronic lung diseases (lung cancer, silicosis, etc.). Aim of this study was to evaluate the exposure of Greek construction workers to SiO2 and describe their pulmonary function. The study involved 86 outdoor and underground workers. Medical and professional history was obtained, and breath samples were collected at morning hours through a mask for the determination of SiO2 levels. Pulmonary function tests, radiological examination and evaluation of radiographs were also performed. Pulmonary function examination showed that the majority of the workers were within normal range (61.4%) while the rest were diagnosed with mild (26.5%) and more severe impairment (7.24%). Working conditions (underground-outdoor) were statistically significantly related to the categorization of pulmonary function (P=0.038). During radiological examination, the type of working activity/ conditions (underground-outdoor) were statistically significantly related to the categorization of these findings (P=0.044). Of the 69 employees, 52 did not present findings (75.4%) and 5 were diagnosed with findings specific to occupational diseases (7.23%). Environmental exposure to respirable crystalline silica (RCS) was detected at 0.0125 mg/m3 in the workplace, which is not beyond the legal limits. Underground workers with more than 15 years of exposure to SiO2 are more likely to present chronic silicosis compared to the workers of outdoor activities.

A borehole multifrequency acoustic wave system for karst detection near piles

Karst cavities at or near pile locations pose a substantial danger to underground construction projects. To locate karst cavities at pile locations, advance drilling boreholes are commonly used, but a cavity can be missed due to its limited size. In this paper, we present a new borehole-based technology employing multifrequency acoustic wave (MFAW) detection of karst cavities near drilling boreholes. First, we developed an MFAW detector and signal processing software. The high- and low-frequency transmitters operate in the frequency range of 0.05 kHz to 10 kHz and the range of 1 kHz to 50 kHz, respectively. Next, we evaluated the performance of the prototype in a controlled borehole model. Lastly, the MFAW detection system was tested at a field site. A nearby borehole core was used to verify the MFAW detection results. The testing of the prototype detection system revealed the following findings. (1) The integrity of the rock surrounding the borehole can be assessed by the energy of the high-frequency zero-offset data. The zero-offset section has a high correlation with the energy of the high-frequency detection signal. The rock is intact when the high-frequency detection signal is strong. The rock is fragmented when the test signal exhibits amplitude variance over a short-range away from the borehole. The test signal becomes weak when the borehole meets a karst cavity filled with sand, clay or water. A color bar showing the signal amplitude can represent the integrity of the borehole wall more accurately than a core sample. (2) A karst cavity near the borehole can be detected by low-frequency waves. The low-frequency acoustic detection wave field includes a reflected guided wave from the interface that the borehole meets, the wave in the borehole, and the effective reflected body wave from the karst cavity. The integrity of the rock around the borehole wall obtained by high-frequency acoustic detection can help identify the reflected guided wave. Median filtering suppresses the strong amplitude borehole wave and helps reveal the weaker reflected waves. The reflected wave from the karst cavity near the borehole can be extracted after filtering. (3) The azimuth of the cavity is identified by the different detection recordings of the azimuthal receivers. Reflected wave amplitudes obtained by the azimuthal receivers facing the karst cavity are greater than those obtained by the receivers facing away from the karst cavity. The azimuthal angle can be obtained by the three-dimensional electric compass in the downhole tool. The MFAW detection system is shown to be an effective tool for investigating the geological environments at pile locations in detailed geo-investigation periods.

Comparative spatial predictions of the locations of soil-rock interface

The location of soil-rock interfaces (SRIs) may significantly affect the underground construction works, including the design of underground geotechnical structures. The prediction of the location of SRI using limited borehole data is a challenging task. To address this challenge, this paper presents a comparison study of four methods for spatially predicting the SRI elevation, namely the polynomial regression, spline interpolation, one-dimensional spline regression, and a Bayesian-based conditional random field. The consistencies, prediction accuracies, patterns of the predicted curves, and prediction uncertainties for various methods are evaluated. Borehole data from two sites in Singapore are used in the comparative study. The results show that the spline interpolation method produces the least consistent estimation of SRI profiles. The spline interpolation method also has lower prediction accuracies than the other three methods and cannot provide any information regarding the prediction uncertainty. The spatial trend of the geological interface cannot be captured by the polynomial regression method with a relatively high (i.e., 10) order of the polynomial when faults and folds exist. Advantages of the spline regression method over the conditional random field methods include that (i) it provides a clear and explicit spatial trend of the SRI, which well reflects the geological complexity of the sites; (ii) it avoids the cumbersome estimation of random field parametric values, which is a challenging task under the condition of limited data; and (iii) it can differentiate the zones with different prediction accuracies, which cannot be accomplished by the conditional random field method due to limited data. To sum up, the spline regression method produces a simpler and more informative curve of the SRI than the other three methods and thereby is useful as it can guide site investigations to be carried out at geologically uncertain areas to reduce risks, especially for underground construction projects

Statistical Analysis of the Capabilities of Various Pattern Recognition Algorithms for Fracture Detection Based on Monitoring Drilling Parameters

Ground conditions, including characteristics of fractures, joints, bed separations, and strengths of rock layers, are critical factors for proper design of openings in underground mining and construction projects. Correct understanding of geologic conditions allows for improvement and optimization of ground support design and minimizing incidents of ground failure and instabilities in underground workings. Rock bolts have been widely accepted as the preferred method of ground support in almost all forms of rock excavation applications. The concept of monitoring drilling data to evaluate characteristics of geological features of interest in the rock surrounding the underground opening is a very attractive option for developing the geological model of the ground on real-time basis. This includes information on distributions of joints and bed separations, locations of voids, and strengths of rock layers, which enables the automated and rapid evaluation of ground conditions while drilling is in progress. Several smart drilling systems have been developed and proposed to detect joints; however, they offer limited capabilities and have exhibited difficulties in identifying joints with small apertures. The current study was focused on developing a more sensitive method to locate joints with smaller apertures along the hole being drilled with an instrumented roof bolter. A series of full-scale drilling tests were carried out in samples which contained simulated joints with different inclined angles in controlled laboratory conditions. New joint detection programs, with improved capabilities based on various pattern recognition algorithms, have been developed and used for analysis of data recorded in the full-scale drilling tests. To precisely locate joints, composite parameter was also used to offer more accurate detection. This paper reviews the laboratory testing program, data analysis, logic/algorithms used in the programs, statistical analysis of the detection results, and comparison of the various algorithms for this application.

A novel learning cloud Bayesian network for risk measurement

Bayesian network (BN) is a popularly used approach for risk analysis. Because it is a graphic model being able to deal with randomness yet unable to model ambiguity, the fuzzy set theory is often combined with it to create a so-called fuzzy BN. Instead of using the classical fuzzy set theory, this paper intends to combine a normal Cloud model with the BN. In the normal Cloud model, an element belonging to a certain qualitative concept is not certain and precise as well. The Cloud BN is a generalization of the fuzzy BN. It is more adaptive for the uncertainty description of linguistic concepts, for example, the risks. Using the normal Cloud model, the following numerical characteristics of the variables can be estimated: the expectation, the dispersion degree compared with the expectation, and the dispersion degree of entropy. Consequently, the risk assessment contains a richer set of analytical information. Cloud BNs attract growing research interests. Compared to its precedents, the Cloud BN in this paper has a learning capability. Since the risk factors may have a combined effect, the causal relationships among the variables can be very complex, and hidden variables may exist. The learning mechanism allows for automatic structure discovery from data, giving rise to a dynamically evolving network. The proposed learning Cloud BN is able to represent the real risk situation better than its precedents. Its effectiveness and applicability are demonstrated by an illustrative case for risk prediction of the face instability in an underground tunnel construction project.

Chemical Stability of Framboidal Pyrite Containing Geogenic Arsenic in Alluvial Sediments

The number of underground construction projects is increasing worldwide, resulting in the production of a huge amount of waste excavated material. Excavated soils from alluvial plains are rich in pyrite. When these soils are exposed to air, the pyrite oxidizes, resulting in the generation of H2SO4, which acidifies the soil and releases potentially harmful trace metals and metalloids such as arsenic into the environment. Polarized light microscopy and field‐emission scanning electron microscopy (FE‐SEM) revealed the presence of framboidal pyrite within the shells of microorganisms in alluvial soil samples collected in Japan. Analysis with FE‐SEM/energy‐dispersive X‐ray spectrometry and electron probe microanalysis (EPMA) revealed that this framboidal pyrite contained As. When soaked in distilled water for 6 h or in 1 M HCl for 2 h, the framboidal pyrite remained unchanged; however, when it was soaked in 10% H2O2 for 6 h, it was oxidized and swelling was observed on the surface of pyrite microcrystals. A 1 M HCl extraction test indicated that arsenic release from framboidal pyrite would be difficult under acidic conditions. Framboidal pyrite in alluvial sediment is stable at low pH; however, it is unstable under oxidative conditions, suggesting that waste alluvial soil should be kept under reducing conditions. The chemical stability of geogenic arsenic in pyrite in soils and sediments provides a useful way to determine a correct handling of the soils for reclamation or as a covering material.Core Ideas Chemical stability of framboidal pyrite in acidic or oxidative conditions was examined. Geogenic As was accumulated mostly in framboidal pyrite. Framboidal pyrite was stable in acidic conditions but was unstable in oxidative conditions.

Methods for estimating sediment during tunneling using a mechanized tunneling

Currently, with the development of many cities, the need for transport infrastructure is increasing. Since the free ground space in urban environments is limited, the most effective and efficient exit is the construction of underground structures. Currently, new underground construction projects are being developed in conditions of high density of development, and in many cases in areas where ancient structures and buildings of historical value are located. The effectiveness of design solutions for the protection of objects in the zone of tunneling depends on the accuracy and reliability of methods that assess the impact of factors that have a negative impact. Moreover, if the station complexes are often built in areas with minimal impact on the surrounding buildings, and their construction is carried out by means of small mechanization and small visits, then the construction of tunnels, in the zone of their influence can get buildings of historical and cultural value. The authors of the article have considered both the causes of sediment and empirical, analytical and numerical methods for their evaluation. In particular, among the analytical methods, the method developed in MIIT and based on the reciprocity theorem was distinguished. The article also compares the calculation results for precipitation method Yu.A. Limanowa and calculation in program complex PLAXIS. In the end, the authors give conclusions based on the analysis of all the above methods, as well as recommendations for reducing sediment during tunneling with the use of tunnel mechanized complexes.

Application Research of GPR in Quality Detection of Urban Underground Jacked Pipes Construction

Nowadays, pipe jacking method is usually adopted in the construction of urban underground pipelines. In order to ensure the construction quality of pipe jacking method, geophysical non-destructive prospecting methods are used for detecting the compactness around the jacked pipes. Based on the theory of ground penetrating radar (GPR), the void models of jacked pipes with two different materials (i.e. cement pipe and steel pipe) were established, and the finite element method was used to simulate the 2D forward modeling of GPR. At the same time, combined with the urban underground jacked pipes construction project in Xiangtan city, Hunan province, China, GPR was used to carry out field prospection of the quality of jacked pipes construction. The results of forward simulation and practical applications show that good results can be obtained when GPR is used to detect the construction quality of cement pipes, which is the same as that of using GPR to detect the construction quality of tunnel. But the collected signals are not effective when the steel pipes are detected, which is because the radar signal cannot penetrate the steel pipe, and there are multiple reflections between the radar antenna and the pipe wall. Therefore, new non-destructive prospecting methods are needed for void detection of steel jacked pipes.