The 860-meter-long section of the Xiaopengmen River undergoing restoration in Shanghai’s Jiabei Country Park featured banks composed of silty clay that had long been subjected to water erosion and rainwater runoff. This led to problems such as slope collapses, soil erosion, and riverbed siltation, which not only reduced the river’s flood discharge capacity but also marred the park’s overall landscape.
The project team proactively evaluated multiple options and rejected traditional bank protection methods such as wooden piles, concrete retaining walls, and gabion baskets. Instead, taking into account on-site conditions, construction costs, and ecological maintenance requirements, they selected 4-meter MA718 polymer-coated steel sheet piles for the ecological bank protection work. Leveraging the ecological perforations in the sheet piles, the project simultaneously achieved slope stabilization, riverbank waterproofing, and aquatic ecosystem restoration, thereby enhancing both the engineering quality and service life from the outset.
On-site construction conditions for this project were significantly constrained: the work area was narrow, adjacent to landscape trees and pedestrian walkways; the use of heavy equipment was strictly prohibited; and construction could not be carried out while the river was diverted, with stringent standards for waterproofing and environmental protection.
In response to these adverse conditions, the project team proactively optimized the construction plan by erecting a floating work platform to accommodate water-based construction and selecting small, low-vibration equipment to minimize soil disturbance and damage to vegetation. Prior to construction, the team implemented strict raw material controls, provided sun protection for the sheet piles, cleaned the interlocking joints, and applied waterproofing lubricant to ensure a tight interlock and compliance with impermeability standards.
Meticulous and proactive quality control was implemented throughout the entire construction process. With precise measurement and positioning at the core, control stakes were set up and pile verticality was monitored in both directions to strictly maintain construction deviations within the limits permitted by regulations. Construction crews proactively optimized the pile driving process by adopting a constant-speed interlocking driving method. They performed intermittent operations in sections to release pore water pressure, effectively preventing slippage and deformation in soft soil.
To address the challenges of soft-ground construction, steel clamping plates were proactively used to assist in pile driving, significantly reducing bending, breakage, and material loss of the sheet piles. Upon completion of pile driving, interlock sealing and reinforcement, layered backfilling and compaction, and pile cap installation were promptly carried out to delay material aging. Concurrently, aquatic plants were planted in ecological holes, and river dredging was completed in compliance with regulations, strictly adhering to ecological construction requirements.
Through proactive process optimization and quality control throughout the entire process, construction efficiency was significantly improved, and the overall project duration was shorter than that of traditional bank protection methods. Polymer-reinforced steel sheet piles are corrosion-resistant, age-resistant, and resistant to insect damage, with a design service life of up to 50 years. The project team implemented routine, simple maintenance, significantly reducing long-term operation and maintenance costs.
Construction was carried out with low vibration and minimal disturbance throughout the project, causing no damage to surrounding landscape vegetation. After the bank protection structure was completed, there were no risks of seepage, and the river’s aquatic ecosystem continued to recover. Compared to traditional methods, this approach resulted in lower construction costs and fewer maintenance requirements, yielding significant overall benefits.
The riverbed of the 300-meter pilot section for Yellow River flood control in Ningxia consists primarily of silt and thick layers of soft silt. During the flood season, the water flow is turbulent and the scouring force is intense. The original gabion and geogrid slope protection systems were prone to damage, had high repair rates, and lacked adequate flood control and seepage prevention capabilities.
To enhance the safety factor of the embankment, the project team proactively optimized the support plan by using 6-meter-high, high-strength Z-shaped plastic-steel sheet piles to construct a vertical impermeable bank protection structure, effectively blocking seepage through the embankment body and mitigating the risks of piping and embankment breaches. In response to major challenges such as water flow interference, soft foundations prone to displacement, and high flood control standards, the project team planned ahead, proactively developed specialized construction plans, and comprehensively strengthened process control.
In the early stages of construction, the team proactively carried out site preparation by clearing loose soil and debris from the slope surface, excavating guide trenches, and laying a crushed stone base course to ensure pile driving accuracy and construction stability.
During construction, standardized operations were strictly enforced. Pre-treatment for interlocking waterproofing was completed ahead of schedule, piles were driven with precision in sections, and the waterproofing layer was backfilled and the pile cap poured in a timely manner, forming a complete, closed-loop waterproofing system.
After completion, the project department proactively implemented routine monitoring during the flood season. Following verification over two flood seasons, the embankment showed no seepage or collapse, and the bank protection structure remained stable and reliable. This effectively reduced operation and maintenance costs and provided a proven practical reference for refined, eco-friendly construction of river flood control and bank protection projects.