Newsletter Volume 10, Issue 4 December 2025

 

1. Introduction

The expansion of mining operations in urban and peri-urban areas has posed significant challenges to geotechnical engineering, particularly regarding the construction of retaining structures in structurally and socially sensitive environments.

Traditional pile installation methods, such as impact driving, vibratory driving, or soil jetting, are frequently associated with the generation of high ground vibrations. Peak particle velocities (PPV) can exceed 15 to 30 mm/s just a few meters from the source, potentially compromising the stability of nearby structures, including dams, slopes, and residential buildings (White et al., 2002; Jardine et al., 2005). Standards such as DIN 4150-3 and NBR 12664 establish threshold limits ranging from 6 mm/s to 12.5 mm/s in order to prevent structural damage and minimize discomfort.

In this context, press-in pile technology, based on the Press-in system, stands out by installing piles using static axial force and rotational torque, eliminating the need for dynamic impact or active vibration. This method results in minimal levels of vibration and noise and is widely recognized internationally as a safe and environmentally appropriate alternative for construction near sensitive structures or in densely built urban environments. Studies have shown that press-in piling can reduce ground vibrations by up to 90% compared to percussive methods, maintaining peak particle velocities (PPV) below 5 mm/s even in close proximity to the pile (McNamara & Panchal, 2025; GIKEN LTD., 2024).

Although widely adopted in countries such as Japan, Singapore, and the United Kingdom, the application of this technology in Brazil is still incipient. This study is considered a pioneering effort in the use of retaining structures downstream of a tailings dam. The analysed application is in the Quadrilátero Ferrífero region, an important mining hub in southeastern Brazil, in an area characterized by immediate proximity to a large-scale geotechnical structure (a tailings dam) and by urban settlements located downstream, which imposed strict constraints on vibration generation. In this context, the choice of the GIKEN Silent Piler™ system was driven by the need to preserve the structural integrity of the dam and avoid any interference with the foundations and buildings in the nearby community, making the Press-in technology the only viable option to ensure technical safety, geotechnical stability, and social acceptance of the project.

Therefore, this paper presents the results of vibration monitoring carried out during the installation of the retaining structure using steel piles driven by the press-in system. The analysis emphasizes the quantification of induced vibration levels, modelling of attenuation curves, and assessment of compliance with regulatory limits, with the objective of demonstrating the technical feasibility, operational safety, and environmental advantages of this technology for use in areas with high structural and social sensitivity.

2. Downstream Containment Structure (DCS)

The Downstream Containment Structure (DCS) was engineered as a supplementary physical barrier to the dam’s existing safety systems, specifically designed to retain tailings in the event of a structural failure. The implementation was carried out within a critical interface zone between a major geotechnical structure and an adjacent urbanized area, necessitating a solution that ensured uncompromising structural integrity, accelerated construction timelines, and rigorous mitigation of ground vibrations.

The DCS consisted of two parallel rows of tubular steel piles, each with a diameter of 1,000 mm and a wall thickness of 19 mm, interconnected by steel connectors and filled with concrete. This configuration was designed to ensure resistance against the passage of both solid and fluid materials, as well as to facilitate construction in soil containing boulders and lithological variations.

The installation was carried out sequentially using the Silent Piler™ equipment, which enables static pile driving through hydraulic pressing. The staged operation, with progressive advancement of the equipment over previously installed piles, allowed construction in restricted work areas while minimizing disruptions to access roads and the surrounding urban environment. The pile installation process is illustrated in Fig. 1.

Fig.1 Application of the Silent Piler™ system for the installation of tubular steel piles

 

The technique employed successfully reconciled the project requirements with the environmental and structural constraints imposed by the site, ensuring the containment system’s expected performance and contributing to the integrated safety of the dam-community system.

3. Traditional Pile Driving Methods Compared to the Press-in System

Traditional pile driving methods, such as impact driving, vibratory driving, and soil jetting, despite their widespread use, exhibit significant limitations when employed in areas of high structural, environmental, or urban sensitivity. Impact driving, for instance, can generate peak particle velocities (PPV) exceeding 15 mm/s at 5 meters from the source, accompanied by intense noise and an elevated risk of liquefaction in saturated soils (Tomás et al., 2012). Although vibratory driving is quieter, it still produces PPV levels ranging from 10 to 20 mm/s, potentially causing adverse effects on nearby structures (Jardine et al., 2005).

In contrast, the Press-in system employs static axial force combined with rotational torque, operates without soil removal, and provides precise control over the applied energy. Studies demonstrate that this method achieves peak particle velocities (PPVs) below 6 mm/s even at close distances, making it particularly suitable for applications in urban environments or areas with critical structures (McNamara & Panchal, 2025). Table 1 below summarizes the key characteristics of the pile driving methods, drawing on case studies and technical literature.

Table 1  Comparison between pile driving methods (from White et al. 2002, and Leung et al. 2018).

Driving method	Typical PPV Range (mm/s) at 5 m	Noise Level	Liquefaction Risk	Suitability for Sensitive Areas
Impact	>15	High	High	Low
Vibratory	10–20	Medium	Medium	Moderate
Press-in	<6	Low	Low	High

 

4. Field Investigation of Induced Vibrations from Press-in Technology

The construction of the retaining structure utilized tubular steel piles with a diameter of 1000 mm and a wall thickness of 19 mm, driven to depths ranging from 10.7 m to 23.5 m. The piling process was carried out in four separate campaigns using the Silent Piler™ equipment from GIKEN, which operates via static pressing, eliminating the need for excavation or dynamic impact. The sequential advancement over previously installed piles contributed to operational stability and minimized disturbances in the immediate vicinity of the construction site.

Vibration monitoring was conducted using engineering seismometers located at distances of 3.9 m to 22.5 m from the piles, in two main directions around the monitored geotechnical structure. Each seismometer was equipped with tri-axial geophones, allowing the recording of the three vibration components (vertical, longitudinal, and transverse), as well as derived parameters such as peak particle velocity (PPV) and dominant frequency. Two data acquisition modes were adopted:

• Histogram: continuous recording of the largest amplitudes at 5-second intervals.
• Waveform: automatic activation for full waveform recording when vibration levels exceed 0.13 mm/s (phase 1) or 0.51 mm/s (phase 2).

The equipment uncertainty analysis, based on ABNT NBR 9653:2018, indicated a typical error of ±0.19 mm/s for resulting PPV measurements, with a 95% confidence level. The recordings were compared with data obtained continuously by two stations of the automated induced vibration monitoring system, installed approximately 300 m from the piles, which allowed the validation of the prediction models and verification of the stability of the results on a regional scale.

The site’s geological setting comprises residual soils originating from weathered itabirites and phyllites, characterized by heterogeneous block distributions and a fluctuating groundwater table. This complex stratigraphy significantly influenced seismic wave propagation and vibration response, factors that were incorporated into the calibration and refinement of the numerical models. The spatial configuration of the seismographs and the test geometry are depicted in Fig. 2.

Fig. 2 Positioning of seismographs and instrumentation layout in the field.

The prediction of vibration behavior was performed based on the following empirical attenuation equation, commonly used in studies of induced vibrations:

PPV=K.D^^-α

where:

• PPV = peak particle velocity at the measurement point (mm/s).
• D = distance between the source and the measuring point (m).
• K = coefficient of vibration intensity at the source.
• α = attenuation exponent related to soil properties.

The equation can also be expressed in linearized form:

log(PPV)=logK- a.logD

Where a = log(K) and b = α are constants obtained by non-linear regression. The calibrated models for the monitored directions exhibited an average error below 15% up to 300 m, demonstrating high reliability for use in risk zoning and in the planning of projects requiring stringent dynamic control.
 

5. Results and Discussions

The results obtained during the monitoring of vibrations induced during the construction of the downstream containment structure demonstrated the effectiveness of Press-in technology in sensitive geotechnical environments close to communities. The steel piles were driven using the Silent Piler™, without percussive impact, and the recorded vibration levels confirmed the suitability of the method for locations with urban and environmental constraints.

The maximum PPV value recorded during pile installation was 5.37 mm/s, measured at 5.4 meters from Pile 80, representing the most critical scenario observed. This value remained below the 6 mm/s limit established by DIN 4150-3:1999 for sensitive structures, in the predominant frequency range of the records (10–50 Hz), as illustrated in Fig. 3. Statistical analysis demonstrated that, above 10 meters away, PPV values ​​dropped to less than 3 mm/s and, above 15 meters, they became residual.

This attenuation behavior is consistent with previous studies (White et al., 2002; McNamara & Panchal, 2025) and underscores the Press-in system’s ability to concentrate energy along the pile-driving axis, thereby minimizing lateral vibration propagation. The attenuation curves were fitted based on the maximum values at each measurement point using nonlinear regression.

Fig. 4 presents the consolidated average curve derived from field monitoring data. While the overall model yielded a coefficient of determination (R²) of 0.19, individual fits for each pile showed R² values ranging from 0.41 to 0.71, depending on direction and depth. The mean error remained below 15% up to 22.5 m from the source, indicating the model's suitability for exploratory analysis and its potential to support technical planning of vibration-controlled construction activities.

 

An additional validation was performed using records from two fixed automated monitoring stations positioned between 207 and 394 meters from the piles. The data from these stations remained mostly within the limits estimated by the prediction curves, as shown in Fig. 5. This confirms the reliability of the model even beyond the direct measurement zone, demonstrating its applicability for vibration zoning at the construction scale.

 

The pile analysis indicated that the highest vibration levels occurred during the driving of piles in areas with greater local soil resistance and depth, such as Pile 80. Conversely, the lowest vibration levels were recorded during the installation of piles that were completed more rapidly, with minimal interaction with lithological blocks.

Compared to traditional methods such as percussion and vibro-driving, which often generate PPVs greater than 15 mm/s at 5 meters from the source (Tomás et al., 2012; Coduto et al., 2010), the levels recorded with Press-in were up to 70% lower, with no evidence of liquefaction and greater control of the transmitted energy.

From an operational standpoint, the technique enabled safe and precise pile driving even in confined areas, eliminating the need for excavation and reducing environmental impact. Press-in technology proved to be not only safe and appropriate, but also efficient for construction in restrictive environments, constituting a strategic solution for geotechnical engineering focused on dams and sensitive urban contexts.

6. Conclusions

The adoption of the Press-in piling technology, using the Silent Piler™ system, demonstrated satisfactory technical performance in the installation of a containment structure downstream of a tailings dam, within a geotechnically and urban-sensitive context. Field results indicated that the maximum recorded peak particle velocity (PPV) was 5.37 mm/s, measured at a distance of just 5.4 meters from the pile-driving front, a critical distance representative of the area with the highest dynamic load during construction.

This value is below the threshold of concern of 6 mm/s, as established by DIN 4150-3:1999, for sensitive structures exposed to frequencies between 10 and 50 Hz, such as residential buildings and nearby urban facilities. Furthermore, vibrations attenuated rapidly with distance, with most measurements beyond 10 meters already falling below 3 mm/s. This pronounced dissipation, combined with the static control inherent to the Press-in method, effectively eliminated the risk of liquefaction in nearby geotechnical structures and prevented adverse impacts on the surrounding community.

The fitted attenuation curves exhibited a mean error below 15% for measurements between 3.9 m and 22.5 m, with coefficients of determination (R²) ranging from 0.19 to 0.71. Despite the data dispersion, typical of field conditions in heterogeneous geological settings, the empirical attenuation models offered a reliable reference for understanding vibration behavior during pile installation. These models can serve as a foundation for exploratory zoning and technical planning in future projects. Cross-validation with Automated Monitoring Stations (AMS) demonstrated good agreement in the observed orders of magnitude, reinforcing the model’s practical applicability even beyond the immediate measurement zone.

Among the main technical and operational advantages of the adopted solution, the following stand out:

• Compliance with national and international standards for induced vibration control.
• Safe execution in urban areas near communities and critical geotechnical structures.
• Consistent vibration behavior prediction characterized by low data dispersion.
• Absence of excavation or percussive impact, significantly reducing environmental and social impacts.

This study reinforces the potential of Press-in technology as a modern and sustainable alternative for containment projects involving tailings dams and other sensitive structures, promoting the adoption of low-impact construction methods within the Brazilian engineering context.

Acknowledgments

The authors would like to thank Vale S.A. for its institutional support and technical feasibility of the containment project presented in this study. They would also like to thank VMA – Explosives and Vibrations Engineering for its specialized support in instrumentation and monitoring of field-induced vibrations, which significantly contributed to the quality of the data obtained and the robustness of the analyses performed.
 

References

ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS – ABNT. (2018) NBR 9653: Medição e avaliação de vibrações em estruturas – Diretrizes.

CODUTO, D. P.; YEUNG, M. C. R.; KITCH, W. A. (2010) Geotechnical Engineering: Principles and Practices. 2nd ed., Pearson Education.

DEUTSCHES INSTITUT FÜR NORMUNG – DIN. (1999) DIN 4150‑3: Vibrações em edifícios – Efeitos nas estruturas.

GIKEN LTD. (2024) Silent Piler System Overview and Technical Performance. Disponível em: https://www.giken.com/en

JARDINE, R. J.; CHOW, F. C.; OVERY, R. F.; STANDING, J. R. (2005) ICP Design Methods for Driven Piles in Sands and Clays. Thomas Telford Publishing.

JARDINE, R. J. et al. (2005) Design of Tubular Piled Foundations using the ICP Method. Proceedings of the 16th International Conference on Soil Mechanics and Geotechnical Engineering – ICSMGE, Osaka, Japan.

McNAMARA, A.; PANCHAL, J. (2025) Improving performance and sustainability credentials of existing deep foundations using press-in piling technology. IPA Newsletter, Vol. 10(1), March 2025.

TOMÁS, R.; CANO, M.; PASTOR, M. (2012) Soil liquefaction induced by vibratory pile driving. Engineering Geology, Vol. 125, pp. 1–10.

VMA – ENGENHARIA DE EXPLOSIVOS E VIBRAÇÕES. (2021) Relatório Técnico F18‑PG‑VMA‑ENS‑01 Rev. 02 – Instrumentação e análise de vibrações na ECJ Minervino, Itabira–MG.

WHITE, D. J.; FINLAY, T. C.; BOLTON, M. D.; BEARSS, G. (2002) Press-in piling: ground vibration and noise during pile installation. Cambridge University Engineering Department.