FR2696764A1 - Filling material for viscoelastic joint in civil engineering structure - made from homogenous and self-compacting mixt. based on bitumen, cellulose fibres, crushed sand and gravel - Google Patents

Abstract

The filling material for a viscoelastic joint comprises a homogenous and self-compacting mixt. of modified bitumen-based elastomers, e.g. of styrene-butadiene-styrene contg. an adhesive dope, modified cellulose fibres rich in mineral material, a filler and crushed sand and gravel. The filling material contains 15 - 25 wt.% bitumen; 0.3 - 1 wt.% cellulose fibres; 5 - 15 wt.% filler; 15 - 25 wt.% crushed sand; and 60 - 80 wt.% crushed gravel. USE/ADVANTAGE - To provide continuous surface between concrete structure components, e.g. of road bridge. Easy to handle, self-compacting and suitable for prefabrication. In an example, viscoelastic joint between concrete components is made from a roll (1) which is resistant to a temp. of at least 180 deg. C, and a bitumen-based sealing mixt,. (2) poured on top of it. This is covered by a metal plate (3) and then the filling material, which is laid to the level of the under-surface of the wear coating. The layer of filling material is then covered by a layer of reinforcing mesh, followed by a hydro-carbon wear layer (7).

Description

FILLING MASS FOR CONTINUOUS VISCOELASTIC JOINT

  FOR CONCRETE ART WORK AND VISCOELASTIC JOINT

  INCLUDING THIS FILLING MASS

  The invention relates to a filling mass for a continuous viscoelastic joint for a concrete structure and

  a viscoelastic seal comprising this filling mass

  wise. In the field of construction of engineering structures in

  concrete, it is necessary to provide viscoelastic joints

  continuous ques to resume the movements of translation and rotation to the joints of work These joints are intended to absorb the deformations created by the circulation of 1 O

  vehicles, as well as the extensions resulting from the dilata-

  thermal insulation, to ensure the continuity of the surface between a road and a bridge and to avoid deterioration of

pavement.

  In current techniques for manufacturing continuous viscoelastic joints, such as expansion joints, articulation joints or construction joints, the process

  consists in forcing a rod between the two elements of

  tone, to pour a mass of elastomeric bitumen in the hollow-

  located between the two concrete elements, to cover the mass of elastomer with a cover sheet, to fill the recess in the joint strip with a succession of layers of aggregates coated or percolated with bituminous binder modified as and as they are put in place, and possibly to cover the percolated mass with a

  reinforcing mesh and depositing the wear layer.

  The process step of depositing the layers

  of aggregates is long, tedious, and requires

  site compaction This step also makes the repair

partial of a difficult joint.

  The object of the invention is to avoid the laying of these successive layers constituting the body of the joint, by providing a filling mass, very handy, self-compacting, which can be prefabricated in a coating plant and used as such directly on the site, and responding to

  all requirements for sealing -

  resistance, punching resistance and elongation power

tion at break.

  The subject of the invention is a filling mass for a continuous viscoelastic joint for a concrete structure,

  characterized in that it consists of a homogeneous mixture

  self-compacting gene comprising a modified bitumen based on elastomers of styrene-butadiene-styrene type and containing an adhesiveness dope, modified cellulose fibers rich in mineral matter, an input filler, crushed sand

and crushed gravel.

  This filling mass preferably contains, relative to the total mass of the mixture, between 15 and 25% by mass of bitumen, between 0, 3 and 1% by mass of cellulose fibers, between 5 and 15% by mass of f iller, between 15 and% by mass of crushed sand 0.1 / 3 and between 60 and 80% in

mass of crushed gravel 6/11.

  This filling mass preferably has a sque-

  mineral lette comprising a percentage of voids between 30 and 40%, at least 93% of the voids being filled with

bitumen.

  This filling mass preferably has voids

  residuals in place less than 2%.

  The invention also relates to a continuous viscoelastic joint for a concrete structure, comprising a tube resistant to a temperature of at least 1800 C forced into a trench coinciding with the hollow space located between two concrete elements, a mass of elastic joint based on elastomeric bitumen poured between the two concrete elements and filling the recess, a cover sheet, a filling mass filling the recess of the joint up to the

  height of the underside of the wear layer, a trellis

  Reinforcement lily and a hydrocarbon wear layer, characteristic

  risé in that the filling mass of the recess of the joint consists of a homogeneous self-compacting mixture comprising a modified bitumen based on elastomers of styrene-butadiene-styrene type and containing a dope of adhesiveness, cellulose fibers modified rich in mineral matter,

  filler filler, crushed sand and crushed gravel

  se. The filling mass of this viscoelastic joint preferably contains between 15 and 25% by mass of bitumen, between 0.3 and 1% by mass of cellulose fibers, between 5 and 15 15% by mass of f iller, between 15 and 25 % by mass of crushed sand 0.1 / 3 and between 60 and 80% by mass of crushed gravel 6/11. The filling mass of this viscoelastic seal preferably has a mineral skeleton comprising a percentage of voids between 30 and 40%, at least 93% of the voids

being filled with bitumen.

  The filling mass of this viscoelastic seal preferably has residual voids in place of less than 2%.

  An embodiment of the invention will now be described by way of example.

  The accompanying drawings are intended to illustrate the invention.

  Figure 1 shows a graph showing the results

  states of the stretching tests at rupture of the filling mass according to the invention.

  FIG. 2 represents a continuous viscoelastic seal for which the use of the filling mass according to

  the invention is particularly suitable.

  The joint mass quoted by way of example contains 20% of bitumen 180-220 highly modified with elastomers of the SBS type (styrene-butadiene-styrene) to which is added a

  stickiness dope this stickiness dope is a catio-

  nique, generally an amine or a mixture of amines, intended

  born to promote adhesion between bitumen and aggregate.

  It also contains 0.5% of modified cellulose fibers rich in mineral matter, for example of the Technocel 1004 brand. These cellulose fibers have a cellulose content (dry matter) of approximately 75%, a density of 40 g / l, a humidity of about 6% and a p H of 7 1 The distribution

  particle size by air sieving of these cell fibers

  lose according to the Alpine method gives 80% of inferior particles

  less than 800 µm, 40% of particles smaller than 200 µm and

  15% of particles smaller than 32 µm These cell fibers

  lose provide a three-dimensional fibrous structure in

  mixing and ensure the cohesion of the bitumen-gravel mixture

  l Qns They prevent separation of the mixture during

  manufacturing, transport, installation and compaction and guarantee

  weave the homogeneity of the mixture The mass also contains 9% of a filler made up of mineral powder passing through a 90 um sieve, 20.5% of washed crushed sand

  0.1 / 3 and 70% crushed gravel 6/11.

  After separation of the compounds constituting the mass, the particle size distribution of the mineral particles carried out by sieving through a square mesh sieve of defined diameter (#) gives as result: # 0.09 Pm 10% of particles # 2.60 um 30% of particles # 5.60 Pim approx 35% of particles # 11.2 Pm approx 95% of particles

  The filling mass according to the invention must meet

  dre to certain criteria with regard to sealing, resistance to punching, increased indentation

  between 30 and 60 minutes, and the power of elongation.

  The tightness is measured by the content of voids resi-

  duels on cubes, which must be less than 2%.

  The punching resistance and the increase in indentation between 30 and 60 minutes is measured by punching tests on the same cubes as those used for the measurement of the residual void content, according to the Swiss practice deriving from the DIN standard. 1996 The indentation at 30 minutes must be less than 8 mm and the increase in indentation between 30 and 60 minutes must be less than 25% according to standard SN 640440 A (limit of values

  nominal for bituminous mixes to be poured and waterproofed

tarmac tees).

  The elongation power at break, measured by tensile tests on test pieces, must be greater than 5% -ao The tests carried out on the filling mass mentioned

  as an example gave the following results.

  The residual voids content determined on cubes

  used for punching tests is 1.7%.

  The punching tests gave 7.87 mm of punching in after 30 minutes, 8.10 mm of punching in.

  punch after 60 minutes The increase in indentation between 30 minutes and 60 minutes (, at 30 min / 60 min) is 2.9%.

  Tensile tests on test pieces were carried out to show that the joint mass has an elongation capacity at break greater than 5%. this value is linked to the following criteria: width of the joint on a structure: 50 cm maximum deformation requested: 2.5 cm maximum elongation: 2.5 cm (5%) The 4 tests were carried out as follows: Pouring the joint mass between 2 concrete blocks previously impregnated with COLASLAC TX on their

contact surfaces.

  At a temperature of about 170 C, the joints were stretched until a constant force rupture of 1000 N or

500 N.

  The table below shows the parameters of the 4 tests carried out: 1 bh SF e, = T (mm) (mm) (mm) (mm 2) (N) (k N / m 2) (mm) (%) ( Oc)

  I 215 100 60 12,900 1,000 77.5 9.7 9.7 18

  II 210 100 80 1 6800 1000 59.5 17.8 17.8 17

  III 210 105 90 18 900 1000 52.9 8.7 8.3 16

  IV 220 90 50 11,000 500 45.5 6.7 7.4 17

  1 = joint length measured in mm b = joint width measured in mm h = joint thickness measured in mm s = joint surface measured in mm 2 F = force measured in N 6 = stress measured in k N / m 2 e = elongation at break measured in mm r = strain at break measured in% T = temperature measured in o C The results obtained are shown in the graph in Figure 1 and show that whatever the thickness of the joint, the elongation at break requirement

is respected.

  According to the tests carried out, this filling mass

  meets all requirements for water tightness

  stiffness, resistance to punching, increase in indentation between 30 and 60 minutes and the requirement relating to the elongation power at break.

  The filling mass according to the invention is particularly

  particularly well suited for the creation of a visco-

  continuous elastic as shown in Figure 2 and

  crit below A sausage 1 is forced into a coincident trench.

  cidant with the hollow space located between two elements in

  concrete It is intended to seal the recess and must resist

  ter at a temperature of at least 1800 C. A joint bottom 2 is poured between the two concrete elements to fill the recess It consists of a modified bitumen based on elastomer, for example of the Coljoint N 6 brand. has a strong elastic power The bottom of the seal 2 is covered with a cover sheet 3 intended to prevent the mass

  filling located above does not slip into the recess.

  This sheet 3 allows the free movement of the two parts of the concrete structure The bottom and the edges of the joint are covered with an impregnation layer 4 intended to seal the cracks in the concrete elements and to serve as a layer

  The recess is filled with the filling mass.

  sage 5 cited according to the invention described above as

  example This mass 5 is covered with a trellis of arma-

  ture 6 for example brand ColgrillÈ This trellis of arma-

  ture is covered with a layer of hydrocarbon wear On the edges of the joint, 2 surface grooves 8 filled with a mass for a joint with high elongation capacity, for example of the Coljoint NE brand, are intended to take up the expansion of the structure , without cracking the wear layer, and ensuring continuity between the seal and the

running part of the roadway.

  This 50 cm joint allows the expansion of a span of at least 60 m whatever the period of realization. This type of joint can be used as an expansion, articulation or construction joint and can be carried out in new work or in repair It can also be used for longitudinal joints, in particular to prevent the penetration of water into the body of pavement on

along the borders.

  The filling mass according to the invention has many

  many advantages It is self-compacting and can therefore

  It can be carried out by hand. It can be pref-

  briquette in a coating plant and used as is directly on the site It meets all the standards and requirements for this type of product with regard to sealing, resistance to punching, increased

  indentation between 30 and 60 minutes and the power of elongation

  breaking strength It can be used for all types of viscoelastic seals and thanks to its maneuverability and

  its self-compacting properties, it can be very easy-

  used for repair work.

Claims (7)

  1 Filling mass for continuous viscoelastic joint for a concrete structure, characterized in that it consists of a homogeneous self-compacting mixture comprising a modified bitumen based on elastomers of styrene-butadiene-styrene type and containing a dope adhesiveness, modified cellulose fibers rich in mineral matter,   filler filler, crushed sand and crushed gravel   se. 2 filling mass according to claim 1, characterized in that it contains between 15 and 25% by weight of bitumen, between 0.3 and 1% by weight of cellulose fibers, between 5 and 15% by weight of f iller , between 15 and% by weight of crushed sand 0.1 / 3 and between 60 and 80% of crushed gravel 6/11.   3 filling mass according to one of claims 1 or 2, characterized in that it has a mineral skeleton comprising a percentage of voids between 30 and 40%,   at least 93% of the voids being filled with bitumen.   4 filling mass according to one of claims   1 to 3, characterized in that it has residual voids in place less than 2%.   Continuous viscoelastic joint for a concrete structure, comprising a tube (1) resistant to a temperature of at least 1800 C forced into a trench coinciding with the hollow space located between two concrete elements, a joint mass (2 ) elastic based on elastomeric bitumen poured between the two concrete elements and filling the recess, a cover sheet (3), a filling mass (5) filling the recess of the joint up to the height of the lower face of the wear layer, a reinforcing mesh (6) and a hydrocarbon wear layer (7), characterized in that the filling mass (5) of the joint recess   consists of a homogeneous self-compacting mixture   nant a modified bitumen based on styrene-type elastomers-   butadiene-styrene and containing an adhesive dope, modified cellulose fibers rich in mineral matter, a   filler filler, crushed sand and crushed gravel.   6 continuous viscoelastic joint for a 1 o concrete structure according to claim 5, -characterized in that the filling mass contains between 15 and 25% by weight of bitumen, between 0.3 and 1% by weight of fiber cellulose, between 5 and 15% by weight of filler, between 15 and 25% by   weight of crushed sand 0.1 / 3 and between 60 and 80% gravel lon crushed 6/11.   7 Continuous viscoelastic seal for a structure in   concrete according to one of claims 5 or 6, characterized in   that the filling mass has a mineral skeleton comprising   as a percentage of voids between 30 and 40%, at   minus 93% of the voids being filled with bitumen.   8 continuous viscoelastic joint for a concrete structure according to one of claims 5 to 7, characterized in that the filling mass has residual voids in place less than 2%.