FR2573337A1 - Method for producing concrete parts comprising projecting inserts and mould for implementing it. - Google Patents

Abstract

The present invention relates to a method for moulding concrete parts in moulds comprising joints, especially vibrated concrete parts, and a mould for implementing it. In accordance with the method at least one portion of at least one element delimiting the joint is heated, and the mould, which can be dismantled into portions capable of being separated from the finished part, is characterised in that some of these portions are equipped, over at least a portion of their surfaces for joining in pairs and possibly on their edges or surfaces in contact with the surfaces of the inserts, with heating elements. The invention applies especially to the manufacture of vibrated concrete parts comprising inserts projecting on their faces which are in contact with the mould.

Description

Process for the production of concrete parts comprising falsely projecting inserts and mold for its implementation.

The present invention relates to the production of concrete parts, in particular vibrated concrete parts comprising inserts, that is to say embedded parts of metal or other material which protrude on one or faces of the part. This is the case in particular of concrete parts forming counterweights, bases or the like which have fixing plates which protrude with respect to the mass of concrete to allow it to be joined to various mechanical parts.

According to the technique previously used, holes are reserved in the mass of concrete for the passage of fixing bolts or drowning in the mass of bolts, and the fixing plates are secured to the concrete part by means of said bolts. This technique has various drawbacks and for example the need for mounting the fittings on the molded masses, the possibility of taking games, etc.

When one wants to drown the insert in vibrated concrete, it is necessary that the insert penetrates into the mass of concrete through the necessarily flat surface which constitutes the free upper surface of the mold. This prevents many parts from being produced or makes it necessary to mold the parts in several installments, which has a major drawback due to a possible lack of adhesion of the concretes successively poured and due to the work involved in such a process.

The present invention is based on the observation that a waterproof joint to the laitance of vibrated concrete can be produced by ensuring accelerated setting of the concrete at least in the vicinity of the joint by heating the portion of at least 1000C. minus an element delimiting the joint.

The mold used for implementing the process must be removable into parts capable of being separated from the finished part, namely from the molded concrete block and the protruding parts of the insert. The mold according to the invention is characterized in that some of these parts are provided on at least part of their junction surfaces between parts and optionally on their edges or surfaces in contact with the surfaces of the inserts, with heating elements.

In such a method of manufacturing molded concrete parts in which a milt tight joint is produced by heating the concrete to a temperature close to the evaporation of water in the vicinity of the joint, the duration of the heating must be limited for limit the setting depth of the concrete.

In addition, the parts of the mold provided with such a heating means are expensive members that cannot be economically left in place until the concrete has set completely.

According to another characteristic of the method applied to the production of vibrated concrete parts, removable heating parts of the mold are used over their entire surface which are removed after the vibration operation.

 It is formed during the vibration of a practical duration of ten seconds and in contact with the heating parts a layer of concrete having made at least partially taken which is sufficient to maintain in shape until complete setting the mass of vibrated concrete.

The invention also relates to a mold for molding concrete parts, in particular with undercuts, comprising removable parts capable of being heated.

over their entire surface in contact with the mass of molded concrete.

In summary, the process is characterized by at least one of the following points: a) at least part of at least one element delimiting the joint is heated.

b) the heating temperature is close to 1000C.

c) heating the entire surface of the removable parts of the mold.

d) the heating parts are separated from the mold and from the mass of vibrated concrete immediately after the vibration period.

Claims (6)

Claims 1. A method of molding concrete parts in molds comprising joints, in particular of vibrated concrete parts, characterized in that at least part of at least one element delimiting the joint is heated. 2. A method according to claim 1, characterized in that the heating temperature is close to 1000C. 3. A method according to any one of claims 1 and 2, characterized in that the entire surface of the removable parts of the mold is heated. 4. A method according to any one of claims 1 to 3, characterized in that the heating parts are separated from the mold and from the mass of vibrated concrete immediately after the period of vibration. 5. A mold for implementing the process which can be dismantled into parts capable of being separated from the finished part, characterized in that some of these parts are provided on at least part of their junction surfaces between parts and possibly on their edges. or surfaces in contact with the surfaces of the inserts, of heating elements. 6. A mold according to claim 5, characterized in that it comprises removable parts capable of being heated over their entire surface in contact with the mass of molded concrete.