Read the latest issue of Terra et Aqua featuring articles covering dredging projects as well as the topics of safety, socio-economics, technical innovations and the environment.
Articles in this issue
Read the complete issue containing articles, upcoming events, an interview and book review.
Clay is one of the three most commonly encountered soil types in riverbed and seabed, other than sand and silt. A major mechanical property of clay is the adhesion factor that reflects the ratio between its cohesive and adhesive strength under different water content. Currently, this adhesion factor is not exactly known. It is important however, to get a better understanding of the relationship between cohesive and adhesive forces, since large surfaces on dredging tools can generate a lot of resistance, therefore slowing production. In this study, experiments were undertaken to determine the actual relation between adhesion and cohesion. The results can help the implementation of analytical cutting models, in turn, allowing the optimal cutting angle in dredging practice to be calculated.
From an early fascination in oceanography, nature has played a defining role in the career of Dr Todd Bridges. With a decade’s investment in the Engineering With Nature® initiative, he has seen that sustainability and engineering can go hand-in-hand providing economic, environmental and social benefits. His focus now is to build on that foundation – to encourage and facilitate collaboration across sectors, public and private, to advance and accelerate Engineering With Nature practice.
Today’s challenges of erosion, flooding and storm surges are primary concerns for coastal communities around the world. Traditional coastal engineering solutions, such as concrete seawalls or rock breakwaters however, will become unsustainable due to their limited resilience, higher costs, societal impacts and unwanted ecological side effects. In response to these challenges, Coastbusters developed a nature-based solutions approach to sustainable coastal management. These solutions will create new habitats based on known ‘biobuilder species’ in the form of biogenic coastal reefs. The purpose of the reefs is to induce natural accretion of sand, attenuate storm waves and reinforce the foreshore against coastal erosion, thus adding to coastal protection.