Showing papers on "Mortar published in 1969"

Method and device for removing mortar or the like from between superimposed rows of bricks or the like

Abstract: A method of removing mortar from between the rows of superimposed bricks while collecting the dust generated thereby and a blade guard for a grinding disc with a tangential dust outlet.

Low density concretes and their manufacture

Abstract: A PLASTIC CONCRETE OR MORTAR MIX INCLUDING AN INCORPORATED GAS SUCH AS ENTRAINED AIR, AND FROM ONE TO TEN GRAMS OF SHORT FIBRES PER POUND OF CEMENT UNIFORMLY DISTRIBUTED THROUGHOUT THE MIX.

Additive for concrete and mortar

Abstract: The invention relates to an additive or mixture for improving the workability and strength and reducing the air content of inorganic binder, and especially hydraulic cement-containing compositions such as concrete and mortar. The additive comprises sulphite waste liquor and certain polyalkylene glycols and their derivatives. The invention also relates to the binder-containing compositions comprising the additive and methods of making the same.

Composition and method for sealing mortar-coated pipe

Abstract: A CORROSION-PREVENTING SEALER COATING CAN BE APPLIED TO MORTAR-COATED PIPE WITHOUT WAITING FOR THE MORTOR TO CURE IF THE SEALER IS A LIQUID, ESSENTIALLY SOLVENT-FREE MATERIAL OF THE PROPER FLOW CHARACTERISTICS TO FROM A SUBSTANTIALLY PINHOLE-FREE, CONTINUOUS LAYER OVER THE IRREGULARITIES OF THE ROUGH MORTAR SURFACE, AND CURES AT ROOM TEMPERATURE INTO A HARD, MOISTURE-IMPREVIOUS COATING BY THE USE OF A WATER-COMPATIBLE, NON-ACID CURING AGENT. A PIGMENTED AND THICKENED SUBSTANTIALLY SOLVENT-FREE EQPXY RESIN COMPOSITION CURED BY AN ACCELERATED AMIDO-AMINE CURING AGENT IS DESCRIBED AS AN EXAMPLE OF A COATING SYSTEM WHICH SATISFIES THE ABOVE REQUIREMENTS.

The influence of aggregate particles on the local strain distribution and fracture mechanism of cement paste during drying shrinkage and loading to failure

Abstract: This paper introduces some preliminary results from a compre-hensive investigation into the influence of the structure of concrete on its internal and overall deformational behaviour under combined stresses. Two-dimensional plate models were loaded in uniaxial compression and the local strain distribution in the fine mortar matrix around aggregate particles was measured using electrical resis-tance strain gauges and photo-elastic coatings. Triaxial strain measurements at discontinuity and ultimate stress were made on cylindrical specimens, of the fine mortar matrix using a special hydraulic triaxial cell. The local and composite material strains at fracture initiation in the plate models were compared with the corresponding values obtained from the triaxial compression tests on the fine mortar matrix and uniaxial compression tests on idealized “three dimensional” concretes. Results indicate that the presence of aggregate particles alters considerably the local strains in the mortar matrix. The restraining influence of strong, hard aggregates induces shrinkage cracks in unloaded specimens which may or may not weaken the material depending on the local and applied stress states. For the models tested under uniaxial compression, cracking was initiated in the mortar matrix at composite material strains which were smaller than for the pure mortar and decreased with increasing volume fraction of coarse aggregate.

Method for the construction of brick walls

Abstract: A wall of bricks is built with perfect alignment in a comparatively short time and with less mortar than is generally used in comparable walls. Each of the bricks in the wall has at its top a groove which has on each of its sides upwardly extending lips so that a caulking ruler can be positioned in the grooves of contiguous bricks to align them and a sled filled with mortar can be pushed over the top of a tier of bricks to deposit mortar on either side of the groove and thereby prepare the tier of bricks for a subsequent tier.

Sulfate soundness : sulfate attack and expansive cement in concrete

Abstract: : The paper discusses the physical and chemical effects of the phenomena associated with the formation of hydrated sulfates in concrete, aggregate, paste, and mortar. The relation of the physical properties of the material surrounding the locus at which the hydrated sulfate is produced to the amount of expansion that results, the degree to which the expansion can be reduced by restraint, the force required to prevent expansion or to prevent the reaction from taking place, the consequences of the restraining force being uniaxial, biaxial, or triaxial rather than hydrostatic are considered. (Author)

Device for electro-osmotic drainage of a building

Abstract: Drying equipment uses electrodes in horizontal planes in brickwork or masonry, set in holes perpendicular to wall plane. Spaces between electrodes and sides of holes are filled with lime-cement mortar containing additive of: For iron electrodes: iron salts, for copper electrodes: copper salts, for aluminium electrodes: aluminium salts, preferably constituting 5% of the mortar.

Electric insulators with spigoting elements

Abstract: A method and apparatus for developing a column, which column comprises a plurality of substantially conical elements supporting one another in a spigoting arrangement, one seated in the other. The elements are connected to one another by a substance such as mortar. The walls of the elements are shaped such that when mortar is introduced in a controlled manner into one of the elements, there is a controlled discharge of the temporarily fluidized mortar along the ducts of prescribed contour constituted by the opposing wall surfaces of an adjacent interfitted element.

Anhydrite mortar floor coating

Abstract: Ground coating has a horizontal surface on a carrier substrate. Anhydrite mortar is used as after addition of a substance which slows the sedimentation of the solids in the water and increased the fluidity of the mass. The water/solids wt. ratio is 0.17-0.5, to obtain a fluid mass which is then cast on the substrate and spreads out to form a horizontal surface, then solidifies in this state. Pref. the added substance is a resin based on amino-S-triazine with at least 2 NH2 groups, modified by a sulphinic or sulphonic acid.

A roman mosaic pavement rebuilt

Abstract: A Roman mosaic pavement, first century, from the Villa Livia, was removed from that site at some time between 1863 and 1897. In the latter year it was acquired for the Isabella Stewart Gardner Museum, Boston, and was installed in the court of that building by 1902. The ground beneath it was not firm. The pavement sank and the lime mortar of the setting bed became weak and loose. In 1961 the pavement was repaired by taking out the crumbling mortar and replacing it with a structure of inert materials bound by an epoxy compound and made rigid by a system of aluminium screens, bars, and channels.

Mortar models of prestressed concrete reactor vessels.

Abstract: The construction and testing of a small-scale mortar model of a prestressed concrete reactor vessel is described at Oak Ridge National Laboratory to determine to what extent small-mortar models and models of elastic materials, such as epoxy, can be used to investigate the stress distributions and the cracking and ultimate failure modes of prestressed concrete reactor vessels. Mortar model design and fabrication techniques are discussed. Test results for the various steps of the prestressing sequence, for a short creep test period, and for a pneumatic pressure test to failure are presented. Vessel failure was gradual; after extensive concrete cracking, the vessel liner failed with an immediate loss of pressure. The elastic and short-term creep behavior are compared to finite-element analysis predictions. Preliminary comparisons are also made with the test results for a second identical mortar model, tested hydraulically, and with the results for a small concrete prototype vessel.

Revetment Construction by Fabriform Process

Abstract: The Fabriform process employs high strength, water-permeable synthetic fabric as a concrete forming material. Water/cement ratio is reduced by forcing vehicle water through fabric, causing substantial increase in strength and very rapid stiffening. Proper fabric design is essential to avoiding mortar loss. Applied to construction of erosion-control revetments, dual wall fabric is placed on the surface to be protected and filled with mortar. The two layers of fabric may be woven together at regular intervals to form filter points providing relief from hydrostatic uplift. A uniform cross section is also available, containing internal fiber reinforcing.

Texturing of concrete pavement

Abstract: PRELIMINARY WORK BY CALIFORNIA ON TEXTURING OF CONCRETE PAVEMENTS IS DESCRIBED. THE PROBLEM HAS RESOLVED INTO TWO GENERAL AREAS: SECURING ADEQUATE TEXTURE DURING CONSTRUCTION, AND MAINTAINING TEXTURE, AS BUILT, BY USING MATERIALS AND CONSTRUCTION PRACTICES THAT INSURE DURABLE SURFACE MORTAR. VARIOUS TEXTURE PATTERNS WERE FORMED INTO THE SURFACE OF LABORATORY-CAST SLABS USING A VARIETY OF PROTOTYPE DEVICES. SKID TESTS WERE PERFORMED ON THESE SLABS. A PROMISING PATTERN WAS SELECTED AND USED ON SHORT SECTIONS OF THREE FREEWAYS. SOME OF THE RESULTS WERE DISAPPOINTING. A UNIFORM TEXTURE OVER A LARGE AREA COULD NOT BE ACHIEVED BECAUSE OF VARYING MORTAR PROPERTIES. IT WAS ALSO DISCOVERED THAT THE PATTERN SELECTED, WHEN FORMED TOO DEEPLY, CAUSED AN ADVERSE REACTION BY SOME VEHICLES. ADDITIONAL WORK IS PLANNED USING OTHER TEXTURE PATTERNS. OTHER SURFACE TREATMENTS INCLUDED BROADCASTING OF SLAG AND SELECTED COARSE SAND PARTICLES ON THE SURFACE WHILE DRAGGING WITH BURLAPS, AND BROOMING. SKID TESTS ARE BEING PERFORMED ON A PERIODIC BASIS, BUT IT IS TOO SOON TO DRAW CONCLUSIONS REGARDING THE LONG-TERM SKID RESISTANCE AS AFFECTED BY TRAFFIC AND WEATHER. NEW CURING COMPOUNDS AND SO-CALLED SURFACE HARDENERS WERE APPLIED TO SHORT TEST SECTIONS OF FREEWAYS IN AN ATTEMPT TO IMPROVE MORTAR DURABILITY. LABORATORY TESTS PREVIOUSLY PERFORMED INDICATED THAT SOME IMPROVEMENT COULD BE EXPECTED FROM THE USE OF BETTER CURING COMPOUNDS AND HARDENERS. AGAIN, THESE TEST SECTIONS HAVE NOT BEEN IN SERVICE LONG ENOUGH TO FORM ANY CONCLUSIONS REGARDING THEIR EFFECTIVENESS. PLANNED FUTURE WORK INCLUDES A CONTINUATION OF TEXTURING STUDIES, A SEARCH FOR EFFECTIVE SURFACE TREATMENTS, A STUDY OF FIELD PRACTICES THAT AFFECT SURFACE MORTAR QUALITY AND TEXTURE, AND ADDITIONAL WORK ON GROOVING OF OLDER PAVEMENTS TO OBTAIN OR RESTORE ADEQUATE SKID RESISTANCE. SPECIFICATIONS WILL BE DEVELOPED AS WORK PROGRESSES TO IMPROVE CHARACTER AND DURABILITY OF THE SURFACE TEXTURE. /AUTHOR/

Machine for cleaning frangible material from solid objects

Abstract: A machine for cleaning frangible material such as mortar from solid objects such as brick by utilization of a reciprocal mass mounted for striking the frangible material at a selected frequency, angle, and penetration.