Four primary pile categories cover the majority of deep-foundation applications. This document outlines the appropriate use-case for each pile type, including load-capacity figures, cost data, and recommended SANY rig models for 2026. Hunan Iron Giant is headquartered in Changsha; our team of engineers possesses over ten years of industry experience to assist you in selecting the optimal pile type and rig for your project site.

1. Introduction

A pile is a long structural element, either driven or bored, that transfers building loads down to a competent subsurface stratum. Selecting the correct pile type helps avoid structural failure and cost overruns.

At Hunan Iron Giant, we supply SANY rig models (SR155, SR205, SR235) for installing these four pile types, both new and certified pre-owned.

Outlined below are the four pile types, along with their installation methods, suitable applications, and key limitations. We also describe our pre-delivery inspection process.

Our export team, with extensive international experience, and our engineers ensure that both technical recommendations and logistical arrangements are delivered to your country seamlessly.

Critical Decision 2026: In 2026, specifying a pile diameter smaller than calculated can result in an undersized foundation, doubling the total pile count and raising overall costs by 18%, according to our case studies. Oversizing merely wastes concrete; undersizing risks project failure.

2. Precast concrete piles (driven)

Selecting a pile type without a prior geotechnical study is the main driver of cost overruns. Our engineers always require borehole geotechnical data prior to preparing any quotation.

A frequent error is deploying driven precast piles in soft soils: low shaft capacity and hammer refusal necessitate additional piles, eliminating the speed‑related advantage.

Within urban environments, percussion drilling or pile-driving without evaluating adjacent properties generates vibrations that crack building facades and give rise to compensation claims. CFA serves as the low-vibration alternative.

Sizing piles based on incorrect load calculations will also lead to failure. Verify the building’s total design load and pile spacing before defining pile diameter, not the reverse.

Concrete traceability is mandatory for 2026 projects: enforce consistent records and real-time logging via SANY telemetry. This is particularly important for CFA piles, where the pile shaft is poured out of sight.

Corrosion risks are often overlooked in marine or industrial environments. Steel and cased piles require protective treatment, and concrete cover thickness must be documented in compliance with ACI 318.

The static load test (ASTM D1143) must never be omitted for critical piles. It represents the only practical validation of bearing capacity prior to applying structural loads.

Logistics for cranes and driving hammers require advance planning. Hunan Iron Giant arranges transport and auxiliary-crane delivery to your destination port to prevent project-start bottlenecks.

Hunan Iron Giant’s 20-point pre-delivery inspection validates the engine, hydraulic pumps, and platform electronics, and includes a full photographic inspection report.

We recommend sharing your geotechnical report with our team. Our engineers will deliver proposed pile type, suitable SANY rig model and testing plan within 48 hours, free of charge.

2.1 When to use them

Ideal for firm soils and projects prioritizing construction speed: these piles are factory-manufactured under controlled quality conditions and installed by driving with a hammer or vibrator.

Their structural strength is predictable, and installation proceeds at high speed; however, they produce substantial noise and vibration.

2.2 Advantages and limitations

Advantages: Factory-controlled quality and rapid installation.

Limitations: Poor performance under high water-table conditions, in very soft soils, or adjacent to ageing buildings.

At Hunan Iron Giant, we specify hydraulic hammers compatible with SANY rig platforms, so pile-driving operations can be integrated within a single equipment fleet.

3. Bored in-situ piles (continuous flight CFA)

3.1 When to use them

The CFA method pours concrete through the hollow stem as the auger is retracted, requiring no casing. It is the preferred solution for soft soils and urban-area projects due to its low-vibration characteristics.

The SR155 CFA is a frequently selected platform for this application, thanks to its compact footprint and advanced controls.

3.2 Advantages and limitations

Advantages: Minimal disturbance to adjacent properties and clean finished pile shafts.

Limitations: Typical maximum diameter of 1.2 m, and sensitivity to poorly mixed concrete.

To ensure pile-shaft continuity, our engineers mandate concrete consistency control plus SANY telemetry logging of drilling advance for every pile.

4. Driven steel piles

4.1 When to use them

Used in wharves, diaphragm walls, and underpinning projects requiring high-strength and slender cross-sections. Installation is completed via driving with a hydraulic hammer.

They support heavy design loads and achieve substantial overall lengths through section welding.

4.2 Advantages and limitations

Advantages: High load-bearing capacity and long-term durability.

Limitations: Require corrosion-protection measures in aggressive environments and produce noise during driving operations.

For marine environments, we recommend protective surface treatment. Where project schedule permits, a cased bored pile is an alternative solution to mitigate long-term corrosion risks.

5. Large-diameter rotary bored piles

5.1 Sizing example

Take an 8-story building constructed over soft fill, with a total applied load of 40 000 t and 3-m pile-to-pile spacing. The geotechnical report indicates a shaft capacity of 25 t/m. For 0.8-m-diameter piles (2.5 m perimeter) with a 20-m shaft length, each pile delivers approximately 62 t capacity. Therefore, roughly 650 CFA piles installed using the SR155 rig are required.

5.2 When the large-diameter method wins

Large-diameter rotary bored piles range from 1.5 m to 3.0 m and support heavy point loads for towers, bridges, and power-plant structures. They are suitable for ground containing boulders or high groundwater flow, conditions under which CFA drilling becomes uncontrollable. Temporary casing together with bentonite or polymer slurry maintains borehole stability and protects adjacent soils. Our engineers dimension pile diameter and rock-socket length for the target bearing stratum, and validate performance via an ASTM D1143 static load test prior to constructing the remaining pile group. Heavier-duty rigs and slurry-handling logistics incur higher per-metre costs; however, the reduced quantity of main piles typically brings project schedule and budget back on track.

When rock lies close to the surface, we recommend deploying the large-diameter rotary SR235 rig. It reduces total pile quantity to only a few dozen main piles and delivers schedule benefits, even with heavier rig and slurry-handling logistics.

Our engineers perform this calculation free-of-charge based on the client’s geotechnical study, and propose the appropriate rig, construction execution plan, and corresponding ASTM D1143 test program.

The savings derived from selecting the correct pile type greatly outweigh the cost of technical consulting: it prevents unnecessary oversizing as well as the far cost-impacted risk of foundation undersizing.

5.1 When to use them

For bridges, towers and heavy loads, the 0.8–3.0 m rotary pile delivers maximum bearing at depths up to 70 m.

The SR235 is recommended for its 235 kN·m torque and mast stability.

5.2 Advantages and limitations

Advantages: Unmatched load-bearing capacity and adaptability to rock conditions.

Limitations: Requires heavy-duty rigs, higher costs per linear meter, and complex slurry-handling logistics.

Beyond piling rigs, Hunan Iron Giant supplies concrete-related machinery, cranes, earthmoving equipment, and spare parts. This enables clients to obtain a fully integrated foundation-and-lifting solution.

Hybrid Combination: In mixed-scope projects, we combine large-diameter rotary drilling for main piles with CFA for the urban perimeter pile grid to optimize schedule and overall cost. Our engineers dimension both pile types using identical load-design criteria.

Pile type	Installation		Diameter		Depth		Ideal use
Precast concrete (driven)	Hammer / vibrator		0.3–0.6 m		up to 30 m		Fast, firm soil
Bored in-situ CFA	Auger + concrete		0.4–1.2 m		up to 30 m		Urban, soft
Driven steel	Driven		0.2–1.0 m		up to 40 m		Walls, wharves
Large-diameter rotary	Kelly rotary		0.8–3.0 m		up to 70 m		Bridges, heavy loads
Type		Allowable load (t)		Strength		Key note
Precast concrete		60–120		High		Factory quality control
CFA		40–100		Medium-High		Low vibration
Driven steel		50–150		High		Corrosion protection
Large-diameter		200–2000		Very high		Master piles
Type		Cost per metre (USD)*		Speed		Limitation
Precast concrete		80–150		Very high		Noise / vibration
CFA		120–220		High		Limited diameter
Driven steel		100–200		High		Corrosion
Large-diameter		300–700		Medium		Heavy rig

Tips

1. Calculate the building load before fixing pile diameter and spacing.

2. Use CFA in urban areas to meet vibration and noise limits.

3. Reserve large-diameter rotary for master piles and bridges.

4. Require a load test (ASTM D1143) on critical piles.

5. Buy the right SANY rig from Hunan Iron Giant with 20-point inspection.

6. Frequently Asked Questions

Q1: Which pile is fastest to install?

Precast driven concrete piles are usually the fastest, as they arrive factory-manufactured and only require driving on-site. CFA ranks second in speed and is preferred within cities for its low-vibration performance.

Q2: Is CFA suitable for soft soils?

Yes, it is exactly the preferred method for soft soils and fill material due to its low vibration and clean finished shaft. The maximum diameter is limited to 1.2 m.

Q3: What load capacity does a large-diameter pile support?

Between 200 t and 2000 t, depending on pile diameter and embedment depth. The SR235 handles diameters up to 3.0 m and depths up to 70 m. It is the preferred option for main piles on bridge and tower projects.

Q4: Do steel piles require protective treatment?

Yes, within aggressive or marine environments they need corrosion-protection treatment to guarantee long-term durability. Service life remains very long under dry, sheltered conditions.

Q5: Which standards govern pile bearing capacity?

ACI 318 for concrete design, ASTM D1143 for static load testing, and Eurocode 7 for European geotechnical design. ISO 45001 covers construction-site installation safety.

Q6: When should hammer driving be avoided?

Avoid hammer-driving near ageing buildings or within very soft soils, where vibration and driving refusal create risks. In those scenarios, CFA or micropiles deliver better results.

Q7: Which SANY rig do you recommend?

SR155 for urban CFA applications, SR205 for general-purpose work, and SR235 for large-diameter piles and bridge projects. Our engineers validate equipment selection via load‑calculation analysis.

Q8: Where can I buy certified machinery?

At Hunan Iron Giant (https://www.hunan-iron-giant.com/), backed by our 20-point inspection and genuine SANY after-sales support. We refurbish the engine and hydraulic pumps prior to dispatch and deliver machines to your port using our in-house logistics team

7. Conclusion

There is no universal pile: each type matches a soil, a load and an environment. With this guide and the SR155, SR205 and SR235 platforms, you can specify the optimal solution in 2026, backed by our our engineers and Hunan Iron Giant's review process.

Free Personalised Advice

Need to size the piles for your building? Talk to our our engineers for free: WhatsApp +86 195 7293 2608 | Email: Manager@hunan-iron-giant.com | https://www.hunan-iron-giant.com/