Optimization of Shoreline Stabilization Using Geosynthetic-Reinforced Soil Wall for Coastal Urban Infrastructure

Project Abstract

This study investigates the optimization of shoreline stabilization for coastal urban infrastructure through the application of a geosynthetic-reinforced soil (GRS) wall, integrating geotechnical performance, hydraulic resilience, and sustainability metrics. The research develops a robust framework that combines experimental testing, numerical modeling, and field validation to evaluate the effectiveness of GRS walls in resisting lateral earth pressures, wave forces, tidal fluctuations, and scour-induced instability. Laboratory tests on reinforced-soil specimens establish key geosynthetic parameters, including connector strength, reinforcement spacing, and wall geometry, while cyclic triaxial and direct shear tests quantify shear strength envelopes and frictional behavior under varying hydration cycles representative of coastal environments. Complementary small-scale wave flume experiments simulate hydrodynamic loading, sediment transport, and seepage effects to capture interaction mechanisms between wave action and vertical face stability. A calibrated finite element model incorporating nonlinear material behavior, seepage, and contact interfaces enables parametric analyses of wall height, reinforcement spacing, anchor details, face inclination, and drainage optimization, aiming to minimize deformation, maximize stability against sliding and overturning, and reduce overtopping risk. The optimization framework employs multi-objective criteria, balancing construction cost, material durability (including UV, corrosion, and biofouling considerations), constructability, maintenance accessibility, and environmental impact, with constraints drawn from regional coastal codes and climate projections. Sensitivity analyses identify critical parameters driving performance, such as reinforcement gain-to-weight ratio, soil compatibility, and backfill compaction practices. The study also investigates long-term performance under scour cycles, storm surge scenarios, and sea-level rise, incorporating probabilistic reliability assessment to quantify failure probabilities and service life. Field implementation along a representative coastal segment validates design recommendations by monitoring settlement, tilt, pore-water pressure, drainage efficiency, and nearshore hydrodynamics over multiple seasonal cycles. Findings indicate that properly engineered GRWall configurations with optimized reinforcement spacing and hybrid drainage strategies substantially reduce lateral displacements, maintain adequate factor of safety during extreme events, and suppress seabed incision, while delivering cost-effective and environmentally considerate stabilization. The research demonstrates that GR walls can be tailored to regional geology and hydrodynamics, enabling adaptive design that accommodates projected climate variability. Practical outcomes include an evidence-based design procedure, a decision-support tool for reinforcement layout and backfill selection, and a maintenance protocol emphasizing inspection intervals and rapid retrofit options. The study contributes to the literature by integrating reinforced-soil mechanics with coastal hydraulics, providing a replicable methodology for other urbanized coastlines, and offering policy-relevant guidance for infrastructure resilience in the face of evolving coastal hazards. The optimized approach shows potential for synergistic applications in quay walls, tidal barriers, promenade fortifications, and waterfront redevelopment projects, promoting safer, sustainable, and economically viable coastal urban infrastructure.

Project Overview

What This Project Is About

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A straightforward exploration of how a geosynthetic-reinforced soil wall can help protect coastlines and nearby urban areas from erosion and flood risk. The project looks at design ideas, performance, and practical use in coastal infrastructure.

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The Problem It Addresses

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Coastal regions face erosion, wave action, and rising water levels that threaten roads, buildings, and ecosystems. Traditional shore protections can be costly or environmentally disruptive. The project investigates a lighter, potentially cheaper, and adaptable solution that can be implemented in urban coastal settings.

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Objectives of the Project

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1. Explain how geosynthetic-reinforced soil walls work in shoreline protection.
2. Assess basic design options suitable for small to medium coastal projects.
3. Evaluate factors like soil type, tides, and waves that affect performance.
4. Estimate construction costs and maintenance needs.
5. Provide practical guidelines for safe and effective implementation.

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What You Will Do Step by Step

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1) Review simple background information on shoreline protection and geosynthetics. 2) Identify common coastal conditions where the solution could be used. 3) Create simple design sketches and selection criteria. 4) Compare lightweight performance with basic simulations or rules of thumb. 5) Estimate costs via basic budgeting and case examples. 6) Discuss environmental and maintenance considerations. 7) Prepare a short set of practical recommendations for engineers.

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Expected Outcome

A clear, easy-to-use guide outlining when and how a geosynthetic-reinforced soil wall can be a viable coastal defense option, with basic design ideas, cost considerations, and maintenance tips.