US2190003A - Process of fixing and impermeabilizing soil masses - Google Patents

Description

Feb. 13, 1940. J. VAN HULST 2,190,003

PROCESS OF FIXING AND IMPERMEABILIZING SOIL MASSES Filed June 16, 1936 r/Ver [zed INVENTOR L/A/V I A/v H0457 ELM ATTO R N EY Patented Feb. 13, 1940 UNITED STATES PATENT OFFICE PROCESS OF FIXING AND IMIPERMEABILIZ- ING SOIL MASSES Application June 16, 1936, Serial No. 85,530 In the Netherlands July 19, 1935 3 Claims.

This invention relates to a process for fixing and immobilizing, and contingently impermeabilizing sand and earth masses, particularly such as are in permanent or intermittent contact with 6 water with a free water level, as is the case, for

, instance, with river-beds, shores, beaches, sandbanks or shoals along coasts or in tidal rivers, canaland riversides, dikes, seawalls, moles, breakwaters, and the like.

- The process according to the present inven tion constitutes a further improvement of the processes described in my prior U. S. applications Serial No. 668,033, filed April 26, 1933, Serial No. 25,184, filed June 5, 1935 (Patent No. 2,158,025,

15 May 9, 1939) Serial No. 25,379, filed June 7, 1935 (Patent No. 2,075,244, March 30, 1937) Serial No. 51,602, filed November 26, 1935 (Patent No. 2,051,505, August 18, 1936); Serial No. 59,490, filed January 17, 1936; and Serial No. 60,062, filed 20 January 21, 1936, according to which processes pervious or loose subsoil layers and other masses are impermeabilized and/or fixed by causing aqueous dispersions of bituminous substances, which may also contain finely-divided filling 25 substances, to penetrate into the soil or mass under treatment and to coagulate at the desired place or depth.

In applying said prior processes for fixing and immobilizing sand and earth masses, which are 80 in permanent or intermittent contact with water with a free water level, difliculties may arise in consequence of the mass thus treated still having insufilcient cohesion to resist the erosive action of the running water or waves.

85 It is also known to fix shores, banks and the like by providing a stone-setting or stone-dumping, but then there is the risk of thesand or earth behind or underneath the stones being washed away, with the result that the stone-setting or stone-dumping may fall into decay or subsidence after some lapse of time. Such stone-dumpings are also applied for protecting the bottom of rivers and canals, or in making constructions in the sea in order to prevent 46 erosion of the soil, but even when, for instance,

a wattle-work is used as a basis for the dumping it may occur that the underlying earth is washed away.

I have now found that sand or earth masses,

50 which are in permanent or intermittent contact with running water, sea waves or other water with a free water level, can be fixed and immobilized, and contingently impermeabilized,

by the use of aqueous dispersions of bituminous 55 substances, asphalt, tar, pitch, parafiin wax,

resins, rubber or the like, or mixtures thereof, or mixtures of such dispersions with finely divided filling substances, in the manner as described in the above-mentioned prior patent applications in combination with the application on top thereof of some coarse material, such as a stone-setting or a stone-dumping, or a covering with mats, plaited screens, wattle-work, osiery, reed or the like, or such a covering with on top thereof a stone setting or dumping. Said coarse 0 materials may be applied either before or after the treatment of the sand or earth mass with the dispersion. On the one hand the said coarse materials protect the earth mass impregnated with bitumen or other dispersed substances against the erosive action and wash of' the'running water and waves, while on the other hand the stone-setting, stone-dumping or other covering is protected against collapse or subsidence, since the impregnated, underlying sand or earth can no longer be washed away.

The aqueous dispersions to be used in the present process must be adapted to the soil to be treated, just as is the case when applying the processes described in the above-mentioned prior applications. Fillers to be added to the dispersions of bituminous or the like substances are, for example, colloidal clay, Portland cement, lime, limestone powder, fine sand, micro-asbestos, infusorial earth, trass, shale powder, coal 0 dust and the like. The dispersed bitumen may also be treated with substances which tend to improve the adhesion of the bitumen to mineral aggregates, such as heavy metal soaps, high molecular organic acids and the like. The bind- 5 ing capacity of the bitumen may also be improved by adding to the dispersion a few percents of rubber latex or rubber. dispersion. I In the accompanying drawing, Figure I,II, and III illustrate the manner of carrying out the 40 invention according to the embodiments thereof described below in Examples I, II and III, respectively.

Example I This relates to the repairing of a shore protection consisting of a stone-setting on a sandy subsoil, said setting having wholly or partly collapsed owing to the sand having been carried away by the washof the waves.

After the stone-settinghas been replaced in its original position, pipes are inserted in the subsoil close behind and parallel with the stonesetting. These pipes, the bottom ends of which are open, are filled with gravel up to a certain level. A bitumen dispersion containing 10% bitumen and 2% clay, prepared with soap as emulsifier and, if necessary, with the addition of a known stabilizing agent, is injected into the pipes. the pipes are slowly pulled up so as to allow the dispersion to spread regularly over the whole height of the shore wall and to produce a proper impregnation of the sand layer underlying the stone-setting. The stability of the dispersion is regulated so as to produce its coagulation after a suitable time of contact with the soil constituents, whereby the desired cohesion is obtained.

Example I I This relates to the local fixing of a sea floor with a view to the construction of a mole, in order to prevent the washing away of the soil from underneath .the mole construction. A series of injection pipes, which may be inter-connected, are introduced into the soil at a depth of about 50 cm., and through these pipes a 30% bitumen dispersion is injected, containing as emulsifier 1% wood tar and 0.5% sodium hydroxide, both ingredients calculated on the weight of bitumen. While the dispersion is injected the pipes may preferably be pulled in the horizontal direction through the sea floor or shifted in some other way, the soil thus being more or less loosened, which promotes the injection. Thereafter the mole is constructed in a known manner by setting or dumping stone.

Example III This relates to the fixing of a sandy river-bed. A caissonor bell-shaped body is let down onto the bottom of the river, the side-walls of the said body being caused to sink partly into the soil. An aqueous dispersion containing 20% hard bitumen, prepared with 2% naphthenic acids and 0.5% sodium hydroxide (calculated on bitumen) as emulsifier, and to which 10% rubber latex (calculated on the total weight of dispersion) has been added, is pumped into the hollow space During the injection of the dispersion of the caisson above the soil. The dispersion will penetrate into the soil, the quantity of dispersion being such that the soil is impregnated to a sufiicient depth, and its stability being such as to secure coagulation after a short time. After the caisson has been removed, the impregnated river-bed is covered with stones.

I claim: I

1. A process for fixing and impermeabilizing soil masses, particularly those in contact with freely moving water, comprising applying an impregnating material including a dispersion of a binding agent coagulable in situ to an upper layer of the soil mass and applying a covering of'a coarse, relatively heavy material over the surface of the soil mass whereby to protect said impregnated layer against the erosive action of running water in contact therewith, and whereby said covering is protected by said impregnated soil mass from collapse or subsidence.

2. A process for fixing and impermeabilizing soil masses, particularly those in contact with freely moving water, comprising impregnating an upper layer of the soil mass with an aqueous dispersion of bitumen coagulable in situ, and applying over the soil mass thus impregnated a covering of a coarse, relatively heavy material whereby to protect said impregnated layer against the erosive action of running-water in contact therewith, and whereby said covering is protected by said impregnated soil mass from collapse or subsidence. r

3. A process for fixing and impermeabilizing soil masses, particularly those in contact with freely moving water, comprising covering the surface of the soil mass with a coarse, relatively heavy material and impregnating the upper portion of the soil mass beneath the coarse, rela-' tively heavy material with an aqueous dispersion of bitumen coagulable in situ whereby said material is protected against collapse or subsidence and said impregnated portion of the soil is protected by said material against the erosive action of running water.

' I JAN VAN HULST.

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