04 November 2024
G2 AVP Study: Geotechnical Mission for Securing Bénodet
The G2 AVP geotechnical mission (Preliminary Design) represents a key phase in assessing risks and designing solutions to strengthen and preserve infrastructures in areas with high natural risk. Recently, Infraneo Nantes won a G2 AVP mission for Bénodet, a coastal area in Southern Finistère, Brittany, which faces growing threats from sea breaches and marine submersion.
Context and Challenges of the Geotechnical Mission
Located on the Atlantic coast of Southern Finistère, Bénodet is a coastal site where the Community of Municipalities of Pays Fouesnantais is implementing security initiatives to protect the environment and local infrastructure. The area has been classified as a Major Flood Risk Area (TRI) due to its vulnerability to sea breaches, where seawater temporarily floods the land due to extreme weather phenomena, large swells, or rising sea levels.
The mission entrusted to Infraneo aims to:
- Analyze the soil and subsoil of the area to understand its mechanical and geological characteristics.
- Study land development solutions to enhance protection against submersion risks and improve the resilience of coastal structures to natural hazards.
What is a G2 AVP Study in Geotechnics?
The G2 AVP geotechnical study is a thorough analysis conducted prior to construction works. It involves several technical steps aimed at:
- Studying the geological characteristics of the terrain to anticipate soil reactions to built structures.
- Assessing natural risks such as landslides, erosion, and submersion.
- Defining constructive solutions and geotechnical recommendations to limit the effects of marine phenomena.
Objectives of a G2 AVP Mission in Coastal Areas
In the context of the Anse du Trez, the main objectives are:
- – Limit the impacts of sea breaches by proposing structures resistant to water pressure and erosion.
- – Protect the coastline while preserving its natural environment.
- – Ensure the resilience of infrastructures in a climate change context that increases coastal risks.
Geotechnical Investigation Methods Used for the Study
To accomplish this mission, the Infraneo Nantes teams will deploy a series of advanced geotechnical investigation techniques. Among these techniques, we find:
- Destructive drilling: These drills involve boring into the ground to gather information on the composition and strength of the terrain. In coastal areas, these drills are crucial for detecting soil layers that may be affected by seawater.
- Pressiometric tests: These tests measure soil resistance by applying pressure at different depths. They help assess soil stability and determine recommendations for constructions that can withstand pressure variations caused by waves and rising waters.
- Dynamic cone penetration tests: This method involves inserting a penetrometer into the ground to test its compaction and hardness. It is particularly useful for identifying sandy or clayey soils and anticipating risks such as landslides or settlement.
- Laboratory tests: From the samples collected during drilling, detailed analyses are conducted to evaluate the chemical and mechanical properties of the soil, ensuring that land development solutions take all technical aspects into account.
Resilience Challenges in the Face of Climate Change
Resilience to coastal risks is now a priority for many coastal communities. Predictions indicate an increase in the frequency and intensity of extreme events due to climate change. In this context, Infraneo Nantes' mission in Bénodet makes perfect sense.
G2 AVP geotechnical studies provide valuable answers for communities by helping them:
- – Anticipate the future climate impacts on infrastructures.
- – Implement adaptation solutions that combine both protection and sustainability.
- – Reduce maintenance costs of structures thanks to infrastructures designed to withstand long-term climatic events.
Infraneo, a committed player in securing coastal areas
The Anse du Trez project perfectly illustrates the essential role of geotechnical studies in protecting sensitive coastal zones. Thanks to solid technical expertise and the use of advanced investigation methods, Infraneo Nantes is doing everything possible to secure the coastline of Southern Finistère.
This G2 AVP mission embodies a clear commitment to protecting at-risk territories, thus contributing to a sustainable and resilient approach to coastal development.
