A biophysical model for seedling establishment in mangrove forests

Mangrove seedling establishment is crucial to the long-term development of mangrove forests. This study incorporates a process-based approach for seedling establishment in a process-based hydrodynamic model. The biophysical model is used to simulate seedling establishment in the Firth of Thames estuary (New Zealand). The results are compared to...

An investigation on salt marsh resilience to sea-level rise and increased storm intensity

Salt marshes are ecosystems with significant economic and environmental value. They provide numerous services, including nutrient removal, habitat provision and carbon sequestration (Barbier et al., 2011). They are also widely recognised as nature-based solutions for coastal defence due to their ability to buffer storm waves (Leonardi et al.,...

Analysis of nonlinear ship-induced 3d wave fields using nonlinear fourier transforms

In the past decade, observations in the German estuaries such as the rivers Elbe and Weser show increasingly serious damage to bank protection structures (groins and revetments). This damage is caused mainly by waves induced by the passing of big container ships in the shallow and narrow maritime waterways. These ship-induced 3D wave fields...

Effects of the fineness of densified silica fume on the hydration of Portland cement

As one of the mineral admixtures, silica fume (SF) with high pozzolanic reactivity is generally used to improve the properties of concrete. Most commercial silica fume used in concrete project is dry densified silica fume (DSF). It consists of a good deal of agglomerates of sizes ranging from 10 μm to several millimeters. The size of the...

Multi-level chemical characterization of dutch fine recycled concrete aggregates: a comparative study

In the Netherlands, beside cement replacement with more green cement types, there is also an urgent need for alternative materials for natural sand in new concrete in order to make it circular. Furthermore, the recyclers have raised questions regarding upscaling and the potential of fine recycled concrete aggregates (fRCA) in structural concrete...

Effect of ultra-fine fly ash on the mechanical and shrinkage properties of ultra-high performance concrete

This paper reports on a study to determine the possibility of using ultra-fine fly ash (UFA) for partial or total replacement of normal fly ash (NFA) in ultra-high performance concrete (UHPC). Workability, microstructure, porosity, drying shrinkage as well as mechanical properties were comprehensively studied to investigate the influence of UFA...

Application of ultra-fine fly ash as cement replacement for sustainable concrete with optimal packing design

In the present study, a proprietary 0.2 tonne/h Dusty Cloud Separation (DCS) technology prototype by Value Ash Technologies NV (Belgium) was used to obtain ultra-fine fly ash as a novel by-product. Two types of Class F fly ash were used: separated fly ash (FA1) with particle size < 9.3 μm and ultra-fine fly ash (FA2) < 4.6 μm as sub-fraction of...

Effect of fine aggregate on rheological properties of ultra-high performance concrete（UHPC)

In this paper, four kinds of ecological fine aggregates (manufactured sand, recycled sand, aeolian sand and river sand) were used to prepared UHPC, the effects of the fine aggregates on the workability, rheological properties and mechanical properties of UHPC were studied. The results reveal that the type and content of fine aggregate have an...

Closing the loop of EOL concrete

Production of waste materials, via industrial and human activities, creates big environmental and economic problems but also opportunities to recover valuable resources. EU28 currently generates 461 million tons per year of ever more complex Construction and Demolition Waste (CDW) with average recycling rates of around 46%. There is still a...

Fluidization system for liquefaction tank

For the experimental investigation of the static liquefaction of a slope of water-saturated fine sand first a uniform submerged sand layer is composed in a large liquefaction tank by applying fluidisation by upward flowing pore water from the bottom of the tank. Subsequently a submerged slope is created by applying hydraulic suction-dredging....