Hydraulic Engineering Brochure (PDF - 965 Kb)

HYDRAULIC ENGINEERING, WITH CARE FOR THE ENVIRONMENTDEC is a subsidiary of the DEME Group(Dredging, Environmental and MarineEngineering). For more complex and verydemanding projects, DEC can combine its know-how with the resources that are available withinthe Group, for achieving an optimal and efficientresult.The choice of the right materials, technicallysuitable execution methods and, above all, ateam of enthusiastic and experienced staff mem-bers, has made it possible for DEC to developinto a leader in its area of specialisation.Due to its technological leadership, DEC hasbecome an internationally recognised environ-mental contractor, and we have been active in avariety of different co-operative projects, withpartners at a local, regional and global level.MULTIDISCIPLINARY HYDRAULIC STRUCTURESIntegration of a fish spawning location in the natural surroundings of the Leie River.Inset: Photo taken after completion of the worksLarge photo: Photo taken during the following summer season(Ghent, Belgium)INTERNATIONAL ACTIVITIESS617 - WAT - 01ENFibrous stone asphalt forms a relatively thin,plate-like, flexible, water current and wave-resistant revetments for shorelines, water bot-toms and other hydraulic applications. It hasbeen available for many years, as an excellentand cost-effective alternative for the classicalmaterials used in marine applications.Fibrous stone asphalt is a composite material,consisting of crushed stone of a certain calibre,which is mixed with fibrous mastic asphalt. Itmust comply with very strict requirementsregarding quality, both during the preparationand laying thereof, as well as with regard to thelifetime. The result, fibrous open stone asphalt®or fibrous overfilled stone asphalt, depends onthe composition.The addition of inert reinforcing fibres in themastic makes it possible to use more adhesivebitumen, whereby the adhesive properties, theresistance to water currents and flexibility areimproved, without endangering the internal sta-bility of the mixture.FIBROUS STONE ASPHALT IN HYDRAULIC ENGINEERINGConstruction of an environmentally friendly embankment (Belgium)Application of soil protection measures(Harbour of Zeebrugge, Belgium)Fibrous open stoneasphalt®: A patentedtechnologyFibrous open stone asphalt® differentiates itselffrom fibrous overfilled stone asphalt, through adifference in the ratio between fibrous masticand stone grit in the mixture.Its most important properties are:• High stability on steep slopes and excellent resistance to large wave attack and strong water currents• Self-draining and supportive of plant growth• Flexible, durable and maintenance-free• Environment-friendlyFibrous overfilled stoneasphaltIf higher demands are made on the bituminousstructure, in regard to the resistance to hydraulicand mechanical loads and the deformability inreaction to settlements and scour, then a mixtureof fibrous overfilled asphalt can be selected.However, the impermeability of this protectivelayer, and the consequences thereof on the sta-bility of the entire structure, must be taken intoaccount.Member of the DEME groupDEC NV (DEME Environmental Contractors) DEC is specialised in contract work in the area ofhydraulic engineering. For more than 20 years,DEC has been active in the area of basic engineer-ing, detailed engineering and implementation of avariety of hydraulic works, and especially thosewhere special asphalt materials are utilised. Therestoration or the protection of the environmenthas always played a primary role in these projects.One of the applications is the use of fibrous openor overfilled stone asphalt, sand asphalt and othermaterials, for the construction of dams, bank andwater bottom protection at sea, along coastlines,in harbours and along waterways.Particular attention is paid to the restoration, themaintenance and the development of naturalbiotopes, with the help of bio-engineering tech-nologies. Opposite to classical shoreline reinforce-DEC has developed automated laying frames ofvarious dimensions, for the installation of pre-fabricated, fibrous open asphalt mattresses, witha maximum size of 35 x 10 metres. Furthermore,adapted laying frames can be custom-made tothe requirements of the customer.The installation of prefabricated elements can becarried out both on land and from pontoons, byexperienced and specialised personnel that isprovided by DEC.The implementation of bottom protection meas-ures with fibrous open stone asphalt® offersmany advantages:• A very flexible installation;• Durable revetments;• Extensive quality controls;• Fast and flexible application of the materials.Construction of the canal at Strépy (Belgium)HYDRAULIC ENGINEERING, WITH CARE FOR THE ENVIRONMENTAT THE SERVICE OF THE ENVIRONMENT AND THE CUSTOMERProtection of river embankments (Rhine, Germany)Underwater dumps for thestorage of sedimentsThe use of fibrous open stone asphalt® can alsobe applied for the establishment of underwaterdumps, in which dredging and clearance slurrycan be deposited.BOTTOM PROTECTION WITH PREFABRICATED,FIBROUS OPEN STONE ASPHALT®Quay wall protection (Berendrecht lock, Harbour of Antwerp, Belgium)Anchor protection: Artist’s impressionAnchor protection above tunnels and pipelinesTunnels, immersion constructions, cable shafts,pipelines etc. must often be protected againstdamage, caused by natural factors (waves, tidalaction, currents, erosion, etc.) or by mechanicalloads (ship anchors, etc.).DEC offers a technically sensible and cost-effec-tive solution, by using relatively thin, plate-likelayers, which make minimal use of (scarce) rawmaterials.Scour protection of quay wallsThe turbulence that is caused by ships that moorat a quay can cause sand erosion at the toe of thequay wall, which will then be piled up in the middleof the river, channel or dock. The consequence isthat quay walls lose their stability, and also thatthe passage of other ships is hindered.The installation of a strip of fibrous open stoneasphalt®, next to the quay wall, will see to it thatthe turbulence of mooring ships no longer hasany effect on the bottom of the river, channel ordock. Both problems, namely undesirable accu-mulations of sand and loss of stability, are solvedhereby.Since 1980, DEC has gained an excellent reputa-tion as a contractor, for works in the environ-mental and hydraulic engineering area. In theexecution of these works and as far as possible,extensive use is made of environment-friendlymaterials and technologies, which have beendeveloped through extensive in-house research.Numerous public and private customers andresearch companies, laboratories and scientificinstitutes, have already made beneficial use ofour services. Our experience and our care for theenvironment, whereby the emphasis lies on themaintenance and the development of a naturalenvironment, has meant that our know-how andcapacities have been put at the service of bothprivate and public customers, both in foreigncountries and at home.ments. DEC has been active since 1990 in theimplementation of ecologically beneficial systemsin hydraulic works.In contrast to classical building contractors, DECattempts to be a partner and thinks along with thecustomer, in the design and implementation ofcomplex marine projects.Protection of river embankments (Bangladesh)On-shore:• Landing quays• Lock chambers• Bridge pillars• Tunnel protection• Cables and submerged constructions• Protection of old harbour wallsOff-shore:• Pillars of platforms• Pipelines and cablesApplications• Coastlines• Shoreline protection• (Sea) bottom protection• Offshore technologies• Erosion protection• Underwater protection of pipelines, tunnels, etc.• Research and development en ontwikkeling• Studies and design• Bioengineering• Environment-friendly shore protection systems.Hydraulic worksEmbankment protection of a salt marsh area(Doel, Belgium)Soil protection at the cruise terminal(Harbour of Antwerp, Belgium)Shoreline and water bottom protection withfibrous open stone asphalt® can also be carriedout “on dry land”. For instance, during the con-struction of the “Deurganckdok”, in the harbourof Antwerp at Doel, DEC installed a strip offibrous open stone asphalt® at the level of thefinal bottom of the dock.Soil protection: Schematic presentationSHORELINE AND WATER BOTTOM PROTECTION, WITH IN-SITU FIBROUS OPEN STONE ASPHALT®Construction of a container dock (Deurganckdok, Harbour of Antwerp, Belgium)Spawning locations for fish along canals (Belgium)DEC uses environment-friendly techniques forthe protection of watercourse banks in natureareas. Through a responsible choice of materi-als, and in the combination of various productsand use of bioengineering technologies, valuablesurroundings are created for man, animals andplants.The fibrous open or overfilled stone asphalt®,which is used for an environment-friendly pro-tection of banks, can be installed both in-situand as prefabricated mats. All the advantages offibrous open stone asphalt® are used optimallyin this way. These advantages include flexibility,easy maintenance, environmental friendliness,Construction of environmentally friendly embankments: Schematic presentationENVIRONMENT-FRIENDLY BANKSself-draining properties, offering growth possi-bilities for plants, stability on steep slopes, whileoffering protection against large wave action andcurrents. And DEC can create banks with spawn-ing locations for fish and vegetation zones too, ifrequired by the surroundings.FIBROUS OPEN STONE ASPHALT MATS®ASPHALT MASTICFIBROUS OPEN STONE ASPHALT ®IN SITUFIBROUS OPEN STONE ASPHALT MATS ®SAND ASPHALTFERTILE LAYERGEOTEXTILEHYDRAULIC ENGINEERING, WITH CARE FOR THE ENVIRONMENTDEC is a subsidiary of the DEME Group(Dredging, Environmental and MarineEngineering). For more complex and verydemanding projects, DEC can combine its know-how with the resources that are available withinthe Group, for achieving an optimal and efficientresult.The choice of the right materials, technicallysuitable execution methods and, above all, ateam of enthusiastic and experienced staff mem-bers, has made it possible for DEC to developinto a leader in its area of specialisation.Due to its technological leadership, DEC hasbecome an internationally recognised environ-mental contractor, and we have been active in avariety of different co-operative projects, withpartners at a local, regional and global level.MULTIDISCIPLINARY HYDRAULIC STRUCTURESIntegration of a fish spawning location in the natural surroundings of the Leie River.Inset: Photo taken after completion of the worksLarge photo: Photo taken during the following summer season(Ghent, Belgium)INTERNATIONAL ACTIVITIESS617 - WAT - 01ENFibrous stone asphalt forms a relatively thin,plate-like, flexible, water current and wave-resistant revetments for shorelines, water bot-toms and other hydraulic applications. It hasbeen available for many years, as an excellentand cost-effective alternative for the classicalmaterials used in marine applications.Fibrous stone asphalt is a composite material,consisting of crushed stone of a certain calibre,which is mixed with fibrous mastic asphalt. Itmust comply with very strict requirementsregarding quality, both during the preparationand laying thereof, as well as with regard to thelifetime. The result, fibrous open stone asphalt®or fibrous overfilled stone asphalt, depends onthe composition.The addition of inert reinforcing fibres in themastic makes it possible to use more adhesivebitumen, whereby the adhesive properties, theresistance to water currents and flexibility areimproved, without endangering the internal sta-bility of the mixture.FIBROUS STONE ASPHALT IN HYDRAULIC ENGINEERINGConstruction of an environmentally friendly embankment (Belgium)Application of soil protection measures(Harbour of Zeebrugge, Belgium)Fibrous open stoneasphalt®: A patentedtechnologyFibrous open stone asphalt® differentiates itselffrom fibrous overfilled stone asphalt, through adifference in the ratio between fibrous masticand stone grit in the mixture.Its most important properties are:• High stability on steep slopes and excellent resistance to large wave attack and strong water currents• Self-draining and supportive of plant growth• Flexible, durable and maintenance-free• Environment-friendlyFibrous overfilled stoneasphaltIf higher demands are made on the bituminousstructure, in regard to the resistance to hydraulicand mechanical loads and the deformability inreaction to settlements and scour, then a mixtureof fibrous overfilled asphalt can be selected.However, the impermeability of this protectivelayer, and the consequences thereof on the sta-bility of the entire structure, must be taken intoaccount.Member of the DEME groupDEC NV (DEME Environmental Contractors) DEC is specialised in contract work in the area ofhydraulic engineering. For more than 20 years,DEC has been active in the area of basic engineer-ing, detailed engineering and implementation of avariety of hydraulic works, and especially thosewhere special asphalt materials are utilised. Therestoration or the protection of the environmenthas always played a primary role in these projects.One of the applications is the use of fibrous openor overfilled stone asphalt, sand asphalt and othermaterials, for the construction of dams, bank andwater bottom protection at sea, along coastlines,in harbours and along waterways.Particular attention is paid to the restoration, themaintenance and the development of naturalbiotopes, with the help of bio-engineering tech-nologies. Opposite to classical shoreline reinforce-DEC has developed automated laying frames ofvarious dimensions, for the installation of pre-fabricated, fibrous open asphalt mattresses, witha maximum size of 35 x 10 metres. Furthermore,adapted laying frames can be custom-made tothe requirements of the customer.The installation of prefabricated elements can becarried out both on land and from pontoons, byexperienced and specialised personnel that isprovided by DEC.The implementation of bottom protection meas-ures with fibrous open stone asphalt® offersmany advantages:• A very flexible installation;• Durable revetments;• Extensive quality controls;• Fast and flexible application of the materials.Construction of the canal at Strépy (Belgium)HYDRAULIC ENGINEERING, WITH CARE FOR THE ENVIRONMENTAT THE SERVICE OF THE ENVIRONMENT AND THE CUSTOMERProtection of river embankments (Rhine, Germany)Underwater dumps for thestorage of sedimentsThe use of fibrous open stone asphalt® can alsobe applied for the establishment of underwaterdumps, in which dredging and clearance slurrycan be deposited.BOTTOM PROTECTION WITH PREFABRICATED,FIBROUS OPEN STONE ASPHALT®Quay wall protection (Berendrecht lock, Harbour of Antwerp, Belgium)Anchor protection: Artist’s impressionAnchor protection above tunnels and pipelinesTunnels, immersion constructions, cable shafts,pipelines etc. must often be protected againstdamage, caused by natural factors (waves, tidalaction, currents, erosion, etc.) or by mechanicalloads (ship anchors, etc.).DEC offers a technically sensible and cost-effec-tive solution, by using relatively thin, plate-likelayers, which make minimal use of (scarce) rawmaterials.Scour protection of quay wallsThe turbulence that is caused by ships that moorat a quay can cause sand erosion at the toe of thequay wall, which will then be piled up in the middleof the river, channel or dock. The consequence isthat quay walls lose their stability, and also thatthe passage of other ships is hindered.The installation of a strip of fibrous open stoneasphalt®, next to the quay wall, will see to it thatthe turbulence of mooring ships no longer hasany effect on the bottom of the river, channel ordock. Both problems, namely undesirable accu-mulations of sand and loss of stability, are solvedhereby.Since 1980, DEC has gained an excellent reputa-tion as a contractor, for works in the environ-mental and hydraulic engineering area. In theexecution of these works and as far as possible,extensive use is made of environment-friendlymaterials and technologies, which have beendeveloped through extensive in-house research.Numerous public and private customers andresearch companies, laboratories and scientificinstitutes, have already made beneficial use ofour services. Our experience and our care for theenvironment, whereby the emphasis lies on themaintenance and the development of a naturalenvironment, has meant that our know-how andcapacities have been put at the service of bothprivate and public customers, both in foreigncountries and at home.ments. DEC has been active since 1990 in theimplementation of ecologically beneficial systemsin hydraulic works.In contrast to classical building contractors, DECattempts to be a partner and thinks along with thecustomer, in the design and implementation ofcomplex marine projects.Protection of river embankments (Bangladesh)On-shore:• Landing quays• Lock chambers• Bridge pillars• Tunnel protection• Cables and submerged constructions• Protection of old harbour wallsOff-shore:• Pillars of platforms• Pipelines and cablesApplications• Coastlines• Shoreline protection• (Sea) bottom protection• Offshore technologies• Erosion protection• Underwater protection of pipelines, tunnels, etc.• Research and development en ontwikkeling• Studies and design• Bioengineering• Environment-friendly shore protection systems.Hydraulic worksEmbankment protection of a salt marsh area(Doel, Belgium)Soil protection at the cruise terminal(Harbour of Antwerp, Belgium)Shoreline and water bottom protection withfibrous open stone asphalt® can also be carriedout “on dry land”. For instance, during the con-struction of the “Deurganckdok”, in the harbourof Antwerp at Doel, DEC installed a strip offibrous open stone asphalt® at the level of thefinal bottom of the dock.Soil protection: Schematic presentationSHORELINE AND WATER BOTTOM PROTECTION, WITH IN-SITU FIBROUS OPEN STONE ASPHALT®Construction of a container dock (Deurganckdok, Harbour of Antwerp, Belgium)Spawning locations for fish along canals (Belgium)DEC uses environment-friendly techniques forthe protection of watercourse banks in natureareas. Through a responsible choice of materi-als, and in the combination of various productsand use of bioengineering technologies, valuablesurroundings are created for man, animals andplants.The fibrous open or overfilled stone asphalt®,which is used for an environment-friendly pro-tection of banks, can be installed both in-situand as prefabricated mats. All the advantages offibrous open stone asphalt® are used optimallyin this way. These advantages include flexibility,easy maintenance, environmental friendliness,Construction of environmentally friendly embankments: Schematic presentationENVIRONMENT-FRIENDLY BANKSself-draining properties, offering growth possi-bilities for plants, stability on steep slopes, whileoffering protection against large wave action andcurrents. And DEC can create banks with spawn-ing locations for fish and vegetation zones too, ifrequired by the surroundings.FIBROUS OPEN STONE ASPHALT MATS®ASPHALT MASTICFIBROUS OPEN STONE ASPHALT ®IN SITUFIBROUS OPEN STONE ASPHALT MATS ®SAND ASPHALTFERTILE LAYERGEOTEXTILEDEC is specialised in contract work in the area ofhydraulic engineering. For more than 20 years,DEC has been active in the area of basic engineer-ing, detailed engineering and implementation of avariety of hydraulic works, and especially thosewhere special asphalt materials are utilised. Therestoration or the protection of the environmenthas always played a primary role in these projects.One of the applications is the use of fibrous openor overfilled stone asphalt, sand asphalt and othermaterials, for the construction of dams, bank andwater bottom protection at sea, along coastlines,in harbours and along waterways.Particular attention is paid to the restoration, themaintenance and the development of naturalbiotopes, with the help of bio-engineering tech-nologies. Opposite to classical shoreline reinforce-DEC has developed automated laying frames ofvarious dimensions, for the installation of pre-fabricated, fibrous open asphalt mattresses, witha maximum size of 35 x 10 metres. Furthermore,adapted laying frames can be custom-made tothe requirements of the customer.The installation of prefabricated elements can becarried out both on land and from pontoons, byexperienced and specialised personnel that isprovided by DEC.The implementation of bottom protection meas-ures with fibrous open stone asphalt® offersmany advantages:• A very flexible installation;• Durable revetments;• Extensive quality controls;• Fast and flexible application of the materials.Construction of the canal at Strépy (Belgium)HYDRAULIC ENGINEERING, WITH CARE FOR THE ENVIRONMENTAT THE SERVICE OF THE ENVIRONMENT AND THE CUSTOMERProtection of river embankments (Rhine, Germany)Underwater dumps for thestorage of sedimentsThe use of fibrous open stone asphalt® can alsobe applied for the establishment of underwaterdumps, in which dredging and clearance slurrycan be deposited.BOTTOM PROTECTION WITH PREFABRICATED,FIBROUS OPEN STONE ASPHALT®Quay wall protection (Berendrecht lock, Harbour of Antwerp, Belgium)Anchor protection: Artist’s impressionAnchor protection above tunnels and pipelinesTunnels, immersion constructions, cable shafts,pipelines etc. must often be protected againstdamage, caused by natural factors (waves, tidalaction, currents, erosion, etc.) or by mechanicalloads (ship anchors, etc.).DEC offers a technically sensible and cost-effec-tive solution, by using relatively thin, plate-likelayers, which make minimal use of (scarce) rawmaterials.Scour protection of quay wallsThe turbulence that is caused by ships that moorat a quay can cause sand erosion at the toe of thequay wall, which will then be piled up in the middleof the river, channel or dock. The consequence isthat quay walls lose their stability, and also thatthe passage of other ships is hindered.The installation of a strip of fibrous open stoneasphalt®, next to the quay wall, will see to it thatthe turbulence of mooring ships no longer hasany effect on the bottom of the river, channel ordock. Both problems, namely undesirable accu-mulations of sand and loss of stability, are solvedhereby.Since 1980, DEC has gained an excellent reputa-tion as a contractor, for works in the environ-mental and hydraulic engineering area. In theexecution of these works and as far as possible,extensive use is made of environment-friendlymaterials and technologies, which have beendeveloped through extensive in-house research.Numerous public and private customers andresearch companies, laboratories and scientificinstitutes, have already made beneficial use ofour services. Our experience and our care for theenvironment, whereby the emphasis lies on themaintenance and the development of a naturalenvironment, has meant that our know-how andcapacities have been put at the service of bothprivate and public customers, both in foreigncountries and at home.ments. DEC has been active since 1990 in theimplementation of ecologically beneficial systemsin hydraulic works.In contrast to classical building contractors, DECattempts to be a partner and thinks along with thecustomer, in the design and implementation ofcomplex marine projects.Protection of river embankments (Bangladesh)On-shore:• Landing quays• Lock chambers• Bridge pillars• Tunnel protection• Cables and submerged constructions• Protection of old harbour wallsOff-shore:• Pillars of platforms• Pipelines and cablesApplications• Coastlines• Shoreline protection• (Sea) bottom protection• Offshore technologies• Erosion protection• Underwater protection of pipelines, tunnels, etc.• Research and development en ontwikkeling• Studies and design• Bioengineering• Environment-friendly shore protection systems.Hydraulic worksEmbankment protection of a salt marsh area(Doel, Belgium)Soil protection at the cruise terminal(Harbour of Antwerp, Belgium)Shoreline and water bottom protection withfibrous open stone asphalt® can also be carriedout “on dry land”. For instance, during the con-struction of the “Deurganckdok”, in the harbourof Antwerp at Doel, DEC installed a strip offibrous open stone asphalt® at the level of thefinal bottom of the dock.Soil protection: Schematic presentationSHORELINE AND WATER BOTTOM PROTECTION, WITH IN-SITU FIBROUS OPEN STONE ASPHALT®Construction of a container dock (Deurganckdok, Harbour of Antwerp, Belgium)Spawning locations for fish along canals (Belgium)DEC uses environment-friendly techniques forthe protection of watercourse banks in natureareas. Through a responsible choice of materi-als, and in the combination of various productsand use of bioengineering technologies, valuablesurroundings are created for man, animals andplants.The fibrous open or overfilled stone asphalt®,which is used for an environment-friendly pro-tection of banks, can be installed both in-situand as prefabricated mats. All the advantages offibrous open stone asphalt® are used optimallyin this way. These advantages include flexibility,easy maintenance, environmental friendliness,Construction of environmentally friendly embankments: Schematic presentationENVIRONMENT-FRIENDLY BANKSself-draining properties, offering growth possi-bilities for plants, stability on steep slopes, whileoffering protection against large wave action andcurrents. And DEC can create banks with spawn-ing locations for fish and vegetation zones too, ifrequired by the surroundings.FIBROUS OPEN STONE ASPHALT MATS®ASPHALT MASTICFIBROUS OPEN STONE ASPHALT ®IN SITUFIBROUS OPEN STONE ASPHALT MATS ®SAND ASPHALTFERTILE LAYERGEOTEXTILEHYDRAULIC ENGINEERING, WITH CARE FOR THE ENVIRONMENTDEC is a subsidiary of the DEME Group(Dredging, Environmental and MarineEngineering). For more complex and verydemanding projects, DEC can combine its know-how with the resources that are available withinthe Group, for achieving an optimal and efficientresult.The choice of the right materials, technicallysuitable execution methods and, above all, ateam of enthusiastic and experienced staff mem-bers, has made it possible for DEC to developinto a leader in its area of specialisation.Due to its technological leadership, DEC hasbecome an internationally recognised environ-mental contractor, and we have been active in avariety of different co-operative projects, withpartners at a local, regional and global level.MULTIDISCIPLINARY HYDRAULIC STRUCTURESIntegration of a fish spawning location in the natural surroundings of the Leie River.Inset: Photo taken after completion of the worksLarge photo: Photo taken during the following summer season(Ghent, Belgium)INTERNATIONAL ACTIVITIESS617 - WAT - 01ENFibrous stone asphalt forms a relatively thin,plate-like, flexible, water current and wave-resistant revetments for shorelines, water bot-toms and other hydraulic applications. It hasbeen available for many years, as an excellentand cost-effective alternative for the classicalmaterials used in marine applications.Fibrous stone asphalt is a composite material,consisting of crushed stone of a certain calibre,which is mixed with fibrous mastic asphalt. Itmust comply with very strict requirementsregarding quality, both during the preparationand laying thereof, as well as with regard to thelifetime. The result, fibrous open stone asphalt®or fibrous overfilled stone asphalt, depends onthe composition.The addition of inert reinforcing fibres in themastic makes it possible to use more adhesivebitumen, whereby the adhesive properties, theresistance to water currents and flexibility areimproved, without endangering the internal sta-bility of the mixture.FIBROUS STONE ASPHALT IN HYDRAULIC ENGINEERINGConstruction of an environmentally friendly embankment (Belgium)Application of soil protection measures(Harbour of Zeebrugge, Belgium)Fibrous open stoneasphalt®: A patentedtechnologyFibrous open stone asphalt® differentiates itselffrom fibrous overfilled stone asphalt, through adifference in the ratio between fibrous masticand stone grit in the mixture.Its most important properties are:• High stability on steep slopes and excellent resistance to large wave attack and strong water currents• Self-draining and supportive of plant growth• Flexible, durable and maintenance-free• Environment-friendlyFibrous overfilled stoneasphaltIf higher demands are made on the bituminousstructure, in regard to the resistance to hydraulicand mechanical loads and the deformability inreaction to settlements and scour, then a mixtureof fibrous overfilled asphalt can be selected.However, the impermeability of this protectivelayer, and the consequences thereof on the sta-bility of the entire structure, must be taken intoaccount.Member of the DEME groupDEC NV (DEME Environmental Contractors)