Pile Construction Research Articles

Effects on upper masonry structures caused by double-line parallel shield cutting group pile construction

The effects on the upper masonry structure and the construction parameters of shield cutting piles were studied during shield construction, focusing on a shield interval of Zhengzhou Metro Line 5. The study utilized the actual engineering case of left and right double-lane shields superimposed on cutting cement soil group pile composite foundations beneath masonry structures. Findings revealed that masonry structures within approximately 30 m (5.0 times the tunnel diameter) were impacted before and after shield cut pile construction, resulting in deflection and twisting deformations of houses along the central axes of the left and right tunnel lines. Implementation of “clay shock” grouting outside the shield shell, radial grouting through small conduits, shield tail synchronous grouting, and secondary reinforcement grouting effectively mitigated the disturbance caused by shield construction to the ground. When shield cut piles passed beneath masonry structures, pressure on the soil chamber, total thrust, and cutterhead speed were consistently controlled. Furthermore, the cutterhead torque was appropriately reduced, and slurry injection volume increased, contributing to better control of house settlement.

Environmental Sustainability of Pile Construction Activities in Nigeria; Strategies and Best Practices

: Pile construction activities is a multifaceted activity among the construction activities that are performed by heavy machines, materials and energy sources generating environmental impacts associated with pilling activities such as carbon emissions, noise, heavy vibration, soil instability and groundwater pollution. Sustainable piling construction guarantees that the whole piling process meets environmental sustainability and ultimately human health and wellbeing. Data were gathered through a questionnaire survey administered to construction professionals including engineers, project managers, surveyors, and builders. Out of the 50 questionnaires distributed, 41 responses were analyzed. The study employed the Relative Importance Index (RII) to rank the effectiveness of various strategies in mitigating environmental impacts. The findings underscore the critical role of introducing low-emission machinery and optimizing operational hours in reducing carbon emissions. Noise management was most effectively achieved through alternative pile installation methods combined with regular equipment maintenance. Maintaining adequate setbacks from structures and employing controlled installation techniques were identified as essential strategies to mitigate vibration. Addressing soil instability was found to rely heavily on thorough site investigations and the implementation of effective ground stabilization techniques and preventing groundwater pollution requires the proper use of drilling fluids and diligent site management. These findings contributed to the development of environmentally sustainable practices in pile construction, emphasizing the importance of comprehensive strategies to mitigate the adverse environmental impacts of such activities in Nigeria.

Numerical Analysis of Concrete Hydration Heat Impact on Frozen Soil Temperature around Cast-in-Place Piles.

The hydration heat generated during the concreting of cast-in-place piles causes thermal disturbance to the surrounding permafrost, leading to its thawing. This further affects the stability of the pile foundation and degrades the construction progress. To explore the influence mechanisms of the concrete hydration heat on the permafrost temperature field around the pile, as well as that of different construction seasons on the pile-side boundary conditions and permafrost temperature field, monitoring results of on-site tests and numerical simulation were used to analyze the distribution law of the pile soil temperature field in space and time, and the pile-side boundary conditions and permafrost temperature field during construction seasons. The results show that the temperature trend of the pile foundation can be divided into three stages: a rapid rise phase (0∼2 d), a rapid decline phase (2∼10 d), and a slow decline and stabilization phase (10∼90 d). As the radial distance from the pile center decreases, there occur a corresponding acceleration in temperature increase and an elevated maximum temperature rise (MTR). The influence range of the molding temperature and the hydration heat is about 1∼2 times the pile diameter and less than 1.5 m in the depth direction. Compared to the atmospheric temperature, there is a lag in the change in the permafrost temperature caused by accumulation of ground temperature, and the significant difference between the two leads to an increased rate of heat exchange at the boundary condition. Conducting drilling operation and cast-in-place pile construction in the cold seasons is conducive to reducing the thermal disturbance to the permafrost around the pile in permafrost areas.

Spatial Variability of Sliding Plane on Volcanic Region. Case Study of Sta 21+200 Cisumdawu Toll Road

Landslide can be caused either by natural phenomenon or due to human intervention. Regardless of the triggering factor, once landslide occurs, sliding plane in the form of discontinuity or sometimes referred as sliding plane is formed. Identifying the location and geometry of the sliding plane is important in determining the location of the reinforcement to rehabilitate slope failure. However, it is often difficult to locate the location and geometry of the sliding plane as the sliding direction is also difficult to ascertain. In this paper, slope failure which occurred in STA 21+200 of Cisumdawu toll road is used as case study. Variability of the sliding planes are investigated based on the location of the concrete overbreak that occurred during the bored pile construction on Tuff (volcanic soils) in Sumedang Region. Sliding planes are also estimated based on the soil investigation and pile boring records. The proposed solution is to reinforce the bored piles that did not penetrate into the hard layer with ground anchors installed at the pile cap.

Integrated Assessment of Bearing Capacity and GHG Emissions for Foundation Treatment Piles Considering Stratum Variability

Foundation treatment piles are crucial for enhancing the bearing capacity and stability of weak foundations and are widely utilized in construction projects. However, owing to the complexity of geological conditions, traditional construction methods fail to meet the demand for low-carbon development. To address these challenges, this study introduced a comprehensive decision-making approach that considers the impact of stratum variability on greenhouse gas (GHG) emissions and pile bearing capacity from the design phase. During the design process, the GHG emissions and bearing capacities of deep cement mixing (DCM) and high-pressure jet grouting (HPJG) piles were quantitatively assessed by analyzing the environmental and performance impacts of foundation treatment piles related to materials, transportation, and equipment usage. The results suggest that the bearing capacity of piles in shallow strata is highly susceptible to stratum variability. Using piles with a diameter of 800 mm and a length of 20 m as an example, compared with DCM piles, HPJG piles demonstrated a superior bearing capacity; however, their total GHG emissions were 6.58% higher, primarily because of the extensive use of machinery during HPJG pile construction. The GHG emissions of foundation treatment piles in shallow strata were influenced more by geological variability than those in deep strata. Sensitivity analysis revealed that the pile diameter is a critical determinant of GHG emissions and bearing capacity. Based on the bearing capacity–GHG emission optimization framework, a foundation treatment strategy that integrates overlapping and spaced pile arrangements was introduced. This innovative construction method reduced the total GHG emissions by 22.7% compared with conventional methods. These research findings contribute to low-carbon design in the construction industry.

A case study on early-age cracking of high-strength concrete construction by coupled thermal-mechanical analysis and field monitoring

The use of high-strength concrete (HSC) in constructing high-rise reinforced concrete buildings and their deep foundations is becoming more popular because of the significant reduction in member size and, thus, self-weight in structural members. However, the higher cement content in HSC may result in increased heat of hydration and autogenous shrinkage, growing concerns about forming early-age cracks in HSC structural members. This case study assessed the early-age cracking of HSC in bored pile construction of high-rise buildings. A nonlinear transient coupled thermal-mechanical response analysis was performed to evaluate the potential of early-age cracking caused by the heat of hydration generated in the HSC using ABAQUS and two subprograms, USDFLD and UEXPAN. A 3-D finite element model was developed considering thermal effects, time-dependent evolution of early-age strength and stiffness of HSC, crack strain development, autogenous shrinkage, and stress-relaxation in the analysis. Field measurements were carried out on a 3-m diameter bored pile constructed using Grade C50/60 HSC (fck,cube = 60 MPa) for a high-rise building project in Hong Kong to evaluate the validity of the numerical model. Optical fiber sensors were used to monitor the temperature changes of the pile for approximately 380 hours after casting. The temporal and spatial temperature distributions measured in the field measurements agree well with the simulations. Large thermal gradients and high tensile stress zones were observed across the horizontal cross-sections of the pile, resulting in the formation of vertical annular cracks. Based on the results of the analysis, the maximum crack widths were predicted and compared with the durability crack width limits.

STUDI KOMPARASI KAPASITAS DUKUNG RENCANA DAN KAPASITAS DUKUNG AKTUAL FONDASI TIANG PANCANG PADA KONSTRUKSI SLAB ON PILE JALAN TOL SEMARANG – DEMAK SEKSI 2

Semarang - Demak Toll Road Section 2 with a length of 16.31 km crosses the North Coast of Java. The regional geological map shows that the North Coast of Java has alluvial soil layers with clay and silt characteristics. The results of soil investigations show that the depth of the soft layer reaches more than 60 m. This condition triggers construction engineering to support the Highway above it. One of the efforts to fulfill the elevation plan (finish grade) is the flyover concept with slab on pile construction. The planned traffic lane is laid on a concrete slab which is supported by piles with a diameter of 600 mm. With sufficiently deep soft soil layers, the bearing capacity of the foundation piles is borne by the frictional resistance provided by the soil along the piles. This comparative study compares the planned carrying capacity calculated by the empirical formula with the actual carrying capacity of the field as a result of the PDA Test. Calculations were made on 5 test poles for later comparisons were made with the PDA test record data. For the case of 14 days driving at the research location, the pile bearing capacity from the PDA test results is still below the design bearing capacity. The average actual carrying capacity obtained from the 5 test piles is 278 tons. This value is below the planned carrying capacity of the Shio & Fukui method of 381 tons, Meyerhoff's 355 tons, Biaud et al's 777 tons, and Luciano Decourt's 605 tons. At the age of the pile 14 days after the erection was completed, the results of the calculation of the bearing capacity of the Meyerhoff method are closest to the actual bearing capacity of the PDA test results with a ratio of 1.26. The next method is Shio & Fukui with a ratio of 1.36, Luciano Decourt (2.16), and Biaud et al (2.81). Some of the results of previous studies showed a positive correlation between the age after completion of the pile and the frictional carrying capacity. For this type of friction pile, this is of course very influential, so that it is possible that when it is realized that it is carried out with a longer service life, the actual bearing capacity obtained will increase. This requires further research to obtain a time relationship with an increase in pile bearing capacity, especially for locations that have deep soft soil layers such as in this study location.

Behavior of group of geosynthetic encased granular piles with tire chips- aggregates mixture under static and cyclic loading – A model study

The current study addresses the dual challenges of improving the performance of soft soil beds subjected to static and cyclic stresses and managing the environmental impact of waste tire disposal. This research contributes valuable insights into the sustainable use of recycled tire chips in granular pile construction, coupled with the efficacy of combi-grid encasement for improved soft ground under static and cyclic loading conditions. A series of laboratory model tests were carried out on a group of granular piles to examine the principal parameters, such as the selection of geosynthetic materials and cyclic loading characteristics, including cyclic loading amplitude (qca) and cyclic loading frequency (f). The granular pile composition consists of (25% tire chips + 75% aggregates). The performance of granular piles on improved ground is assessed based on the settlement reduction ratio (Sc,r), accumulation of excess pore water pressure (Pexc), and stress concentration ratio (n). The key findings from static model tests are that the load-bearing capacity is significantly increased with installing a group of ordinary granular piles (= 58%) and substantially increased with combi-grid encasement (= 335%). The effectiveness of ordinary granular piles (OGP) in enhancing the performance of a soft soil bed becomes greater when subjected to lower cyclic loading frequencies (f) and smaller cyclic loading amplitudes (qca). The incorporation of combi-grid encasement greatly enhanced the cyclic performance of a group of granular piles by substantially minimizing cyclic-induced settlement (Sc) across both principle parameters f and qca. This study also examines the increased cyclic stresses on the improved soft bed, resulting in the accumulation of excess pore water pressure (Pexc) development, which is reduced to a greater extent with the help of combi-grid encasement across both principle parameters.

Torsional vibration of tapered pile including circumferential support of surrounding soil

The tapered pile is usually divided into finite segments along the vertical direction due to its variable cross-section when investigating its torsional dynamic characteristics. However, an annular projection would be formed at the contact surface of the adjacent pile segments due to the difference in radius, through which the surrounding soil will apply the circumferential support on the pile segment. In this study, the Voigt model is adopted to model the circumferential support of the surrounding soil acting on the annular projection. On this basis, an amended impedance function transfer method is established combined with the circumferential stress equilibrium equations and circumferential displacement continuity conditions at the contact surface of the adjacent pile segments. The shear complex stiffness transfer method is employed to consider the construction disturbance during pile installation. Then, an improved analytical solution for the torsional vibration of the tapered pile considering the circumferential support of the surrounding soil is established by solving the equations for the soil and pile. Based on the solution, the torsional vibration of the tapered pile is investigated and the influence of the circumferential support of the surrounding soil is revealed under different pile parameters and construction disturbance conditions.

Study on the Impact of Different Pile Foundation Construction Methods on Neighboring Oil and Gas Pipelines under Very Small Clearances

With the acceleration of transportation infrastructure and the densification of transportation networks, there has been an increase in bridge pile construction near oil and gas pipelines. Selecting bridge pile construction methods with minimal impact and reducing the adverse effects of bridge pile construction on nearby oil and gas pipelines are of great importance. This paper uses FLAC3D 6.0 software to simulate and analyze the impact of two different pile construction methods, rotary drilling and impact drilling, on adjacent oil pipelines. The results show that the horizontal displacement of oil pipelines during rotary drilling construction is nearly 90% lower than that of the traditional impact drilling method, and the axial stress is reduced by nearly 85%. Furthermore, numerical simulations of rotary drilling under different conditions were conducted to analyze and summarize the patterns of how different conditions affect construction vibration and stress. This study provides a reference for bridge pile construction near oil and gas pipelines or important buildings.

A Study on the Borehole Wall Stability Analysis and Slurry Ratio Optimization for Construction of Pile in Complex Marine Strata.

In order to address the issue of hole collapse, which frequently arises when boring piles are being constructed in intricate marine strata, this paper discusses the influence of the slurry ratio on the slurry performance as well as the mechanism of slurry wall protection. It performs this by means of theoretical analysis, laboratory ratio testing, engineering analogies, numerical simulation, and field testing. Our findings demonstrate that adding sodium polyacrylate and sodium carboxymethyl cellulose can enhance mud's viscosity, contribute to flocculation, and improve the connection between mud and soil layers. Refering similar engineering cases, three optimization schemes are proposed for achieving a mud ratio that offers wall protection in complex marine strata. Furthermore, the particle flow model of slurry viscous fluid is established. The collapse of holes in the sand layer is reflected in the uneven radial displacement of hole walls and the invasion of mud particles. Increasing the viscosity of mud gradually transforms the uneven radial deformation of pore walls in the sand layer into a uniform radial deformation, whereas increasing the proportion of mud significantly decreases the radial displacement of hole walls. Additionally, when the mud pressure in the hole is 300 kPa and 600 kPa, the wall protection effect is better, and there is no particle penetration by substances such as sand. It is found that a high mud pressure can promote the diffusion of mud particles into the sand layer, while low mud pressure cannot balance the pressure on deep soil. The results of the field tests show that the ratio of water-clay-bentonite-CMC-Na-sodium carbonate = 700:110:90:1.5:0.5 used (where the mass percentage of each material is 77.8% water, 12.2% clay, 10% bentonite, 0.16% CMC-Na, and 0.05% sodium carbonate) can effectively prevent hole collapse and reduce the thickness of the sand layer at the bottom of the hole by 50%.

Construction Safety Risk Assessment of High-Pile Wharf: A Case Study in China

The complexity of the wharf components and the harshness of the offshore construction environment increase the safety risk of hazards, which has highlighted the importance and urgency of safety risk management in high-pile wharf constructions. This paper established a visualized digital construction safety risk model for high-pile wharf based on a so-called FAHP method (the combination of fuzzy comprehensive evaluation (FCE) and analytic hierarchy process (AHP) methods). The construction safety risk indicators were constructed as the target layer, the principle layer and the scheme layer, and then the corresponding safety risk assessment algorithm was established. The physical, functional and safety risk assessment parameters of the component in the BIM model were employed to the safety risk assessment algorithm, and the risk assessment level of each sub-process was subsequently classified. The case study indicated that the high-pile wharf construction project included five elements in principle layer and 15 risk indicators in the scheme layer. Moreover, it was demonstrated that the sub-processes with the highest construction risk level were steel pipe pile sinking in wharf construction and steel pipe pile, steel sheath-immersed pile sinking and embedded rock pile construction in approaches to bridge construction with a risk level of III. In this way, the quantitative visualization of the construction safety risk was effectively realized, which facilitates the safety risk management of construction sites and timely warning and response to unexpected safety accidents.

Application and comparative analysis of Intelligent Monitoring Technology for Grouted Pile Construction based on abaqus

In order to realize the intelligent monitoring of the high-precision positioning of the hole position and the real-time control of the verticality of the pile, an intelligent monitoring system was developed based on the combination positioning technology of BDS and UWB and the biaxial tilt sensor, and the numerical simulation and comparative analysis of the verticality of the pile were carried out by abaqus. The deviation of pile foundation in different directions and the deviation of pile body are controlled by the monitoring system, and abnormal warning is made when the deviation exceeds the permissible range.Through the application of intelligent monitoring system in the pile foundation engineering area of Changshui Airport, it is found that the plane offset and perpendicularity of all piles meet the standard requirements and the construction error is controlled at a small value. The results show that the application of intelligent inspection system can not only ensure the construction quality of pile foundation, but also meet and improve the level of digitization and information technology of smart construction site.

Comparative geotechnical analysis for ultimate bearing capacity of precast concrete piles using cone resistance measurements

Abstract Computing the axial load capacity of pile foundations is often challenging for geotechnical engineers. Different theoretical and empirical approaches were proposed for determining the ultimate bearing capacity. Among these approaches, the in situ testing methods are based on cone penetration test (CPT) measurements. This study compares five CPT methods in estimating the axial load capacity of precast concrete piles evaluated at four piling construction projects in Northwest and Central Florida. The analytical methods used in this work are the Aoki and De Alencar method (1975), the Schmertmann method (1978), the Bustamante and Gianeselli Laboratoire Central des Ponts et Chausees method (1982), the Eslami and Fellenius method (1997), and the Eurocode 7 (2007). The outcomes indicated that the Eurocode method 7 had the most increased load capacity estimates, whereas the Eslami and Fellenius method yielded the lowest estimates. The results also indicated that the Aoki and De Alencar (1975) method consistently demonstrated the slightest differences among these values, showing its potential for reliable and consistent pile-bearing capacity estimations.

Correction effect of jet-grouting on high-speed railway subgrade lateral deformation

Viable remediation of the large lateral deformation of high-speed railway (HSR) subgrades, especially in soft soil areas, is still absent. An integrated rectification scheme of high-pressure jet-grouting (HPJG) combined with stress-release techniques was conducted to rectify the large lateral deformation of an operational HSR subgrade in the soft soil area of China, but without any refined design and mechanical analysis before rectification due to the emergency. The objective of the study is to post-evaluate the rectification effects utilising field monitoring data and numerical calculations. The monitoring data showed that the maximum lateral deviation of the subgrade was 69.1 mm, which almost met the expected correction requirements. However, the influence of the excess pore water pressure (EPWP) dissipation on the correction deviation was not considered in the scheme. Therefore, a numerical model was established to further investigate this effect and corresponding mitigation methods. The calculated results revealed that EPWP in the foundation dissipated mostly within 6 months after rectification, and the deformation loss accounted for 30.7% of the total deviation. Prolonging the interval of two-row pile construction can be a plausible approach to mitigate the deviation loss. The findings provide a feasible method for correcting large lateral deformation of HSR subgrades.

Research On Soil Displacement Prediction Method Caused By High-pressure Jet Grouting Pile Group Construction Under Adjacent Pile Response

This paper analyzes the soil displacement effect during high-pressure jet grouting pile construction by simplifying the construction process as a series of pressure-controlled spherical cavity expansions in a semi-infinite soil medium. Based on the elastic-plastic solution of pressure-controlled spherical cavity expansion theory, a calculation method is proposed to estimate the soil displacement caused by high-pressure jet grouting pile construction. Non-linear contact theory between the pile and soil is introduced, and the finite difference method is employed to determine the internal forces and deformations of the pile. The proposed method is applied to field construction cases, and its validity is verified by comparing the results with on-site monitoring data. The research findings reveal that the soil displacement effect decreases with depth and primarily occurs in shallow soil layers during the construction of individual high-pressure jet grouting piles. The lateral displacement at the ground surface increases first and then decreases with the increase in horizontal distance, while the ground uplift exhibits an exponential decay trend.

Research on the Technology of Full Cylinder Concrete Bite Pile of Deep Riprap Cofferdam

In order to solve the construction problem of deep ripped-rock cofferdam occluding pile under complex geological conditions, this paper studies the occluding pile engineering of Shenzhen-Zhongshan Link Construction pipe prefabrication yard as carrier. The research contents of this paper include the formation of occlusal pile, the reasonable combination of construction equipment, the optimization of concrete mix ratio, the treatment of isolated rock and the demolition of occlusal pile, etc., forming the key technology of the construction of cofferdam concrete occlusal pile under complex geological conditions at sea. Through the construction practice, the application of this technology has obtained a good effect of water sealing, and can provide reference for subsequent similar projects.

Cyclic performance of geosynthetic-encased granular pile with tire chips and aggregates mixture in soft soil – A model study

The performance of encased granular piles subjected to heavy cyclic loading presents a significant concern in the current context. Meanwhile, global waste tire management poses a major challenge because it has a detrimental effect on the environment. To address both difficulties, this research utilizes recycled tire chips derived from end-of-life tires (ELTs) and substituting traditional aggregates in granular pile construction. This study summarizes laboratory model tests investigating the performance of geosynthetic encased granular piles designed for soft soil improvement under vertical cyclic loading. The composition of the granular pile comprised (25 % tire chips + 75 % aggregates). Various cyclic loading parameters were scrutinized, including the selection of encasement material and the best configuration for granular piles, cyclic loading frequency (f), cyclic loading amplitude (qca), length-to-diameter (L/D) ratios, granular pile end conditions, and strength of surrounding soft soil. The novel feature of this research is the evaluation of the cyclic induced settlement (Sc) – excess pore water pressure (Pexc) coupled performance for all considered factors and its effects on the encased granular piles improved soft ground under vertical cyclic loading. Key findings include ordinary granular piles (OGP) illustrated optimal performance when subjected to lower frequency and amplitude loading, smaller L/D ratios, and end bearing conditions. The provision of Combi-grid encasement notably improved the cyclic performance of granular piles by substantially reducing the cyclic induced settlement (Sc) on improved soft beds across all examined factors. This research also discusses the increased cyclic stress on the surrounding soft soil initiated excess pore water pressure (Pexc) development and is reduced to a greater extent with the help of Combi-grid encasement across all test cases.

Challenges and countermeasures in planning, building, and managing electric vehicle charging piles

The widespread adoption of new energy vehicles, particularly electric vehicles (EVs), has created a significant demand for charging infrastructure globally. China, a key player in the EV market, has made substantial advancements in charging pile technology and infrastructure development. However, several critical challenges threaten the sustainability and efficiency of the EV charging ecosystem. This paper identifies and analyzes these challenges, including insufficient planning and construction of charging piles, increased demand for electric energy affecting power grids, high construction costs of fast-charging infrastructure, regional disparities in investment returns, and operational management issues. Moreover, it explores potential strategies to address these challenges. Proposed strategies include optimized planning for charging pile construction, the creation of integrated vehicle-charging-pile platforms, the development of distributed energy systems using blockchain technology, promoting recycling and reutilization of waste charging infrastructure, continuous financial subsidies, and enhanced follow-up operation supervision. Addressing these challenges through comprehensive strategies is essential for China and other nations to establish robust and sustainable EV charging infrastructure, ensuring it meets the growing demand for new energy vehicles in the years ahead. This effort will contribute to a cleaner and more sustainable future for the transportation sector.

Impact of fully rotating steel casing bored pile on adjacent tunnels

Abstract Based on the theoretical model of a soil plug column, the stress analysis of the soil plug column during the spinning process of steel casing is carried out, and the critical depth of the soil column is determined using the stress and torsional shear ratio of the soil column. The effect of factors such as casing wall thickness, surface load, and steel casing spinning speed on the critical depth of soil columns has been explored, and more reasonable construction process parameters have been obtained quantitatively. Combined with the construction of small net distance test piles at a distance of 2.5 m from the tunnel, the impact of the construction process on the existing shield tunnel has been explored. The results indicate that during the construction process, when the wall thickness of the steel casing does not exceed 0.012 m, the surface load does not exceed 15 kPa, the spinning speed of the steel casing is maintained at 5/4/2/4 m/h or 5/3/2/3 m/h (corresponding to soil depths of 2.5/9.5/6/14 m), and the soil height of the soil column is controlled within 11 m, it is not easy to generate soil plug inside the steel casing, and the soil column has strong torsional shear resistance. According to the measured data of adjacent tunnels, it has been found that the construction method of fully rotating steel casing bored pile can effectively reduce the impact on adjacent shield tunnels, and has a good microdisturbance effect, which can control tunnel deformation not exceeding 1 mm and maintain within the warning value range.