A process to manufacture "in situ" safety barriers for roads

Abstract: A process of manufacturing "in situ" of safety barriers for roads and highways, forming these barriers separating members for opposite traffic ways. The process is based in filling a mould with a suitable material whose density is similar to that for concrete, so to get blocks that, near-by disposed, form the barrier on the road. The moulds are placed in the final location to be filled later directly from a concrete-­ mixer truck and to have so the barrier without handling the blocks. The mould can be made of any suitable material (polyester, steel sheet, rigid plastics,....) and will have a higher filler mouth and holes for air exit, as well as lower projections that form legs, so that the barrier that has to be made, remains sligtly separated from the ground and allows the flow of the water under the mould.

Description: The invention relates to a process through which safety barriers for roads and highways are manufactured "in situ". This process is also applicable to manufacturing of special kerbs. In present roads, a member of separation and safety is frequently provided between opposite traffic ways. These protecting members intend to fulfill two main objects, i.e. : a) To prevent a vehicle that has suffered an accident on one carriageway of the road entering in the opposite carriageway. b) To allow the passage of water in case of rain or flood, under the protecting member, so as to avoid stagnation of the water flooding a given carriageway, thereby interrupting the road traffic or possibly causing an accident. One of the prior art ways of manufacturing safety barriers is illustrated on figure 1 and consists in coupling rigidly some sheet strips (1) to small metal pillars (2) nailed to the ground. This safety barrier performs the required functions of seperating, namely absorbing the kinetic energy relating to the mass of a vehicle, and of allowing the water to pass thereunder. Nevertheless, an important problem arises with such barriers, due to permanent deformation thereof in case of shocks, causing high maintenance costs. Another known way of manufacturing safety barriers is illustrated on figure 2. A plurality of mass prefabricated concrete blocks (3) in arched-like shape are joined together semi-rigidly. These blocks are of a sufficient mass to resist a shock with a vehicle and are provided with underside projections or legs (4) so as to allow water to flow or pass thereunder. The usual minimum dimensions of these blocks are 700 mm wide, 800 mm high and 1000 mm long. The volume of each block is about 0,5 m³. Taking into account the concrete density (2,35 Tonne/m³), the mass of each member or block is 1,175 Tonne aprox. In comparison with the manufacturing way of figure 1, the concrete blocks described hereinabove have the advantage that the maintenance is almost null. But, in both cases, the manufactured safety barriers are installed when the road is nearly finished, including in said finishing the rolling layer, road borders, etc. These prior art concrete members present the following drawbacks : The concrete must be white, by using white cement or cements comprising special materials that give the concrete a light-coloured texture. The typical strength is between 150 and 175 Kg/cm² Furthermore, manufacturing of blocks has to be performed in factories provided with a sufficient quantity of moulds. The blocks are obtained by filling the mould with concrete, and then vibrating concrete before setting and subsequent unmoulding of the block. Due to the weight of each block, loading and unloading for storage is only possible with a crane or the like. Storage area for each block has to be 7000 cm² (100 x 70 cm), and the necessarily height is aprox. 77 to 85 cm with legs. In view of the above, it is easy to understand how difficult is storage of the blocks, since they cannot be stacked and must remain near-by. For instance, considering the storage area of the blocks required for manufacturing a road barrier of 10 km, namely the storage area for 10.000 blocks, the minimum storage area must be of 7.000 m², i.e. larger than a football field. On the other hand, handling of the blocks always requires a crane or the assistance of at least one worker. Similarly, with a transport truck of 2,50m x 10m surface, the amount of 1 m long blocks carried is of 35 units maximum. Then, handling of the blocks at least requires two operations, i.e. stacking on road edge and mounting in the final location in the middle of the road. At present, public works depend on the economic factor and also on the termination term. But the time required to finish a road provided with concrete barriers is necessarily long, because of four main disadvantages of the prior concrete blocks : 1) Slow manufacturing. 2) Big stacking areas. 3) High costs, because the use of concrete, provoke high storage costs and supplying delay because of slow making of such blocks. 4) Great difficulty and slow handling, which requires cranes and personnel. A process for manufacturing "in situ" safety barriers for roads according to the preamble of claim 1 is known, e.g. FR-A-2,565,047. In this document, the blocks are simply articulated and not sufficiently rigidly copuled. Furthermore, filling of these barriers produces deformation thereof, which decreases the road security thus obtained. Besides, the document DE-U-7,439,889 discloses a block for a road barrier or median using as a base element a device constructed of precast concrete, with inbuilt sheet metal base and coupling means between adjacent pieces. These coupling means comprise on the one hand a projection provided in one block engaging a groove provided in the adjacent block, and on the other hand a platine connecting the two blocks through threaded roads fixed to the upper end of each block. However, this recess and projection are frail elements which can be easily broken during handling. The object of the present invention is to solve the aforementioned problems. This object is achieved by a process for manufacturing "in situ" barriers for roads, consisting in forming moulds which are then arranged in a predetermined location on the road in order to obtain the barrier, in subsequently filling the moulds with a suitable material to form blocks, said moulds having side coupling means to engage both adjacent moulds, and having on the top at least one filling mouth and holes for air exit, characterized in that said moulds are made of polyester and said coupling means comprise two metallic and rigid roads housed respectively in two tubes of suitable diameter integral with each block, the end of each rod projecting a short distance from the top and bottom of the mould, in order to be attached through fixing means to the projecting ends of a rod, housed in an adjacent block. An embodiment of the process according to the invention is also characterized in that said fixing means are strips fixed by clamping nuts on threaded ends of said rods. A further embodiment of process according to the invention is characterized in that said fixing means are transverse holes provided in said projections of rods for attaching the ends of springs. According to another embodiment, some grooves are provided at the top of the mould to house said strips and nuts. More precisely, the process of the invention is based in achieving a mould which, after being placed in the definitive location on the road, will be filled with a mass of suitable material, being this material any product that has a density similar to concrete. This mould is obtained through a base mould that constitutes a corresponding negative member. The said negative mould is made of polyester. In any case, the weight of the mould per meter must not be higher than 30 kg. The shape of such a mould will be the suitable one for each application, that is for each requirement. As concerns the dimensions of said mould, they will be the suitable ones for each requirement. In comparison with the precast concrete blocks used in above-mentioned conventional systems, it is clear that for the same dimensions, the storage of the moulds, according to the invention, requires a smaller area than the one needed to store the known precast concrete blocks. This is because the latter can be stacked. Likewise, handling of the moulds according to the invention is so that it can be carried to work after terminating the road, to store then in a suitable place, requiring no more than a worker to fill them with the material, from a concrete mixer, through a gravity device. Carrying the moulds is also made easier, owing to their reduced weight, so that it can be carried more units than in the case of concrete blocks. The advantages provided by the process of the invention can be summarized as follows : manufacturing speed making in any colour handling ease marking speed replacement ease minimum and economic maintenance possibility to incorporate soft strip to limit the mould possibility to use the mould or moulds as a marking means, combining units with different colours, for instance, red and white. economy and terms higher finishing quality possibility to make the moulds in any geometric shape, adapted to the requirements of each application. Concept Present system : prefabricated concrete New system Weight in shop 1.100 Kg/m 30 Kg/m Weight finished on the road 1.100 Kg/m 1.130 Kg/m Finishing, texture coarse smooth Stability to agents atmospheric good good Base material concrete only any, with density 2,1 Possibility of smooth and bright colours No Yes Possibility of writing, marking, stripping... No Yes Handling at work Bad Excellent Supply Slow Quick Execution at work Slow Quick Transport Difficult-expensive Easy-cheap Manufacturing Slow Quick Stacking-storage Bad Excellent New designs Difficult Easy Maintenance Good Excellent Spare parts Good Excellent Can save markings? No Yes The aforesaid advantages and others of the process according to the invention will clearly appear from the detailed specification that follows, and which is based on figures 1 to 4, wherein : Fig. 1 illustrates a schematic view of a protection or safety barrier relative to the state of the art defined at the beginning of this specification. As it was discussed, the barrier is made from sheet strips 1 attached to small pillars 2 nailed to the ground. Fig. 2 shows another schematic view of a second safety barrier of prior art explained hereinabove. Here, this barrier is made of concrete blocks 3, mass fabricated joined semi-rigidly together, and provided with under projections or legs 4. Fig. 3 shows a perspective view of an embodiment of mould according to the present invention. Fig. 4 shows another embodiment of the invention with a coupling system, consisting in two metal bars embedded inside the vertical-shaped block, which project from its ends so that fastening is performed through these by nuts and strips or by springs. Referring to the above-mentioned Figs 3 and 4, the process according to the invention is based on a mould 5 than can have any geometric configuration. This mould 5 is provided, on the top, with a filling hole 6 and air exit holes 7. On the bottom of the mould 5 are provided projections 8 acting as supporting legs. The mould 5 can be manufactured in a factory and carried later to work. Then the mould 5 is located it in a definitive place on the road, and filled subsequently with a material whose density is similar to the one of concrete. The filling can be performed directly from a concrete-mixer through a gravity device coupled to the former and, at the opposite end, in front of the filling mouth 6 of the mould 5. A kind of funnel can also be placed on the filling mouth 6. Consequently, the road barriers can be made quickly, requiring, on the other hand, a reduced stacking surface and having the advantage of storing all the required moulds 5 for a road without big costs, because the mould is cheap and filled with concrete only at the last moment, i.e. after location of the mould on the road. In other words, through this process, filling can be performed "in situ", since the filling is made at work, which is not the case for the prefabricated blocks, wherein to be able to fill the mould in shop, it is necessary to wait until the concrete sets and to unmould the blocks before another filling of the mould. In Fig. 4 is illustrated a block 9b, in which means to engage an adjacent block are a pair of rods 13 encased in a concrete block obtained as explained before, with a mould similar to mould 5. The rods 13 are made of a rigid metal and are housed in tubes of suitable diameter, which are integral with the mould. The rods 13 project a short distance through the top and the bottom to receive fixing strips and nuts that will screw onto the projecting and threaded ends of the rods 13, thus forming fixing means between the blocks or moulds 9b. The mould 5 and the block 9a obtained therewith is provided on its top with some grooves 14. Besides, it has been foreseen that the projections of the rods 13 can have a transverse hole, to attach the ends of a spring that, in this case, will constitute the fixing means. The block 9b has also relative lower projections or legs 12b, similar to legs 8.

Claims: Process for manufacturing "in situ" barriers for roads, consisting in forming moulds (5), which are then arranged in a predetermined location on the road in order to obtain said barrier, in subsequently filling the moulds (5) with a suitable material to form blocks, said moulds (5) having side coupling means to engage both adjacent moulds (5), and having on the top at least one filling mouth and holes (7) for air exit, characterized in that said moulds (5) are made of polyester and said coupling means comprise two metallic and rigid rods (13) housed respectively in two tubes of suitable diameter integral with each block (9b), the ends of each rod (13) projecting a short distance from the top and bottom of the mould, in order to be attached to the projecting ends of a rod housed in an adjacent block through fixing means. Process according to claim 1, characterized in that said fixing means are strips fixed by clamping nuts on threaded ends of said rods (13). Process according to claim 1, characterized in that said fixing means are transverse holes provided in said projections of rods (13) for attaching the ends of springs. Process according to claim 2, characterized in that some grooves (14) are provided at the top of the mould (5) to house said strips and nuts.

Inventors: GARCIA BALLESTEROS ANGEL, GARCIA BALLESTEROS, ANGEL
Applicants: GARCIA BALLESTEROS ANGEL, GARCIA BALLESTEROS, ANGEL
Application year: 1988
Main classification: E01F15
IPC codes: E01F15