US2024158A - Playing court - Google Patents

Description

J. F. GALLAGHER PLAYING COURT Dec. 117, 1935,

Patented Dec. 17, 1935 UNITED STATES PATENT OFFICE 12 Claims.

My invention relates primarily to the construction of playing courts for the games of tennis, squash, handball, basket ball and the like, but it is also applicable to the construction of playgrounds, garden paths, athletic and drill grounds, and in fact to any open area where a firm, true, resilient and practically dustless surface for pedestrian use is desired.

Clay, grass and other types of playing courts having surfaces which are not waterproofed and bonded with a permanent cementing medium require considerable maintenance, labor and expense to keep them in uniform condition for use. They require frequent rolling and shaping. Their 1 utility is lessened by the fact that they are softened and otherwise rendered unsuitable for use by rain or excessive moisture. Their principal advantage lies in their shock-absorbing qualities whereby they are rendered less tiring to players than hard surfaced courts as heretofore constructed of concrete or the like.

Hard surfaced courts, however, possess the ad-' vantages of requiring practically no maintenance, retaining their true contours without rolling. They are unaffected by rain and therefore provide maximum availability and they are not damaged by ordinary street shoes as is the ca'se with clay or similar types of courts.

My invention combines the advantages of the clay court and the ordinary hard surface court without the disadvantages of either.

To facilitate an understanding of my invention and the manner of construction whereby these advantages are attained, a detailed description of the characteristic features of construction follows predicated upon the accompanying drawing wherein is set forth by way of illustration, in perspective section, a typical embodiment of the invention in a playing court.

Having reference to the drawing, there is first provided a suitably drained sub-base of earth II and upon the same there is laid a foundation course of dense bituminous concrete l2 employing a mineral aggregate and bituminous cement.

The construction of this foundation course is quite similar to the usual procedure in asphalt road construction, the principal difference being that the mixture used in court construction is somewhat softer than would be practical for road construction. I accomplish this by using a somewhat greater percentage of bituminous cement which produces a mixture of sufficient stability to sustain foot trafiic but of much greater plasticity than would be practical in road construction.

This foundation course, because of the greater amount of bituminous cement, has higher waterproofing qualities than the ordinary road paving mixture. Its greater plasticity furthermore prevents cracking with consequent opening of fis- 5 sures to the infiltration of water from below which would cause deterioration of the upper strata superimposed thereon as will be described later. Cracking of the foundation course usually causes rupture of the superimposed courses, admitting rain water to the interior of the construction as well as to the sub-soil beneath, thus causing deterioration and lessening the supporting power of the sub-soil.

A relatively thinner foundation course of bituminous concrete may be used than if hydraulic cement were employed because of the tendency of the latter to crack due to heaving of the sub-soil by frost or because of the natural forces of expansion and contraction. The bituminous concrete is more or less flexible and will absorb expansion and contraction within itself.

On a sub-soil having fair load-supporting qualities a two inch bituminous concrete foundation is sufficient. be increased or decreased as seems advisable in specific cases. The foundation course as completed is smooth and true as to grade and alignment, free from depressions and ridges.

I apply to the surface of the foundation course a thin waterproofing and cementing flexible coating I3 preferably of bituminous cement either in the unadulterated state or mixed with relatively fine sand to produce an easily workable mortar. The bituminous cement may be rendered liquid either by the application of heat, by mixing with a volatile solvent such as naphtha or benzol, or emulsified and mixed with water. This coating should preferably be applied with a squeegee so as to produce a uniform film over the entire area of the foundation course.

While the bituminous cement coating is still in a liquid state I embed therein a layer of compressed cork slabs or boards I4 of the thickness required to produce the necessary resiliency and effect insulation against heat, moisture, frost and shock; the cork course being say one to one and one-half inches in thickness. These slabs are butted close together in the manner of laying fioor tiles or brick. In the course of this operation a certain amount of the bituminous cement coating I3 is forced upward into the interstices between the individual slabs, thus serving to partly fill the same and also to firmly bond the slabs to the foundation course and form a water- However, this thickness may 25.

proof seal about them. Instead of cork I may employ other materials of equivalent function, such as slabs of compressed fibrous composition, or a layer of material possessing characteristics of flexibility and confined closely related isolated air spaces to impart insulation properties.

I then squeegee over the entire cork surface an application of liquefied bituminous cement IS, the purpose being to completely fill the interstices between the individual cork slabs and also to provide an adhesive upper surface for the application of the next superposed course. In this operation care must be exercised to leave the minimum amount of bituminous cement on the exposed face of the cork. If the joints between the individual slabs are wide enough to admit a bituminous cement-sand mortar, it is advisable to substitute such a mortar for the liquefied bituminous cement.

The wear course I 6 is next applied upon the prepared cork surface. This is done by making a mixture of mineral aggregate and bituminous cement which is then spread upon the cork layer, leveled and rolled or otherwise compressed. The composition of the wear course mixture may be varied to suit individual tastes as to the texture of the wear surface. I find that a mixture which meets general approval is approximately as follows: Fine gravel 55 per cent, mortar sand 35 per cent, and bituminous cement per cent by weight. The bituminous cement used is somewhat harder than is commonly employed in street paving mixtures, having a considerably higher fusing point and being less susceptible to temperature changes. This is desirable in order to overcome the tendency toward bleeding or softening of the bituminous concrete which would normally occur in a mixture having a high percentage of softer bitumen. It also adds materially to the stability of the mixture itself.

The mortar constituent, made up of the sand and bituminous cement, is not quite sufiicient in proportion to the aggregate to fill the voids and tends to settle to the bottom of the layer, thus producing a waterproof bitumen sand and mortar layer in direct contact with the cork layer, completely encasing the cork in a water-tight jacket, and leaving a surface texture having a relatively large percentage of unfilled voids.

I may then spread over the surface and into the exposed voids a mortar I! of hydraulic cement and fine sand in quantities sufiicient to fill the voids with a slight surplus soas to provide a thin film of hydraulic cement above the aggregate, the intent being to fill the voids flush With the projecting aggregate and in effect create within each void an artificial stone of the size and shape of the void itself.

This operation serves the further important purpose of confining the bituminous cement within the wear course, protecting it from direct sunlight and'heat and further overcoming the possibility of the bituminous cement exuding and sticking to the players feet.. It furthermore deflects the 'suns rays and prevents the absorption of heat as would result with a dark bituminous surface.

This wear surface of hydraulic cement mortar may be trowelled, squeegeed or brushed into place, my preference being the utilization for this purpose of a broom with moderately soft hair or fibre which leaves a rugose finished surface marked with minute ridges l8. These provide traction,tending to overcome sliding or slipping and they also reduce to aminimumthe glare from sunlight such as would be reflected by a smoothly trowelled surface. Moreover, the increased radiating surface thus produced aids materially in dissipating the heat absorbed by the surface when exposed to strong sunlight for long periods.

If desired to produce a colored surface this may be done by incorporating in the hydraulic or bituminous cement surface I! finely divided coloring pigments, or substituting for the sand of the mortar a colored mineral aggregate such as crushed slate, crushed brick, etc., or by a combination of both methods. To produce a multicolor or terrazzo effect natural or artificially colored mineral aggregates may be used in the wear course mixture itself or embedded therein by rolling into the surface while plastic.

v The lines of play or other zones may be permanently marked on the playing surface by superimposing upon the cork course strips of rubber I9 or other suitable material of contrasting color and having the thickness of the wear course or by substituting for the hydraulic cement layer I! a mortar similar but of variant color along lines defining such zones so that when the wearing surface is spread and compacted, both the zone marking and the wear surface will be substantially flush and level and thus remain under abrasive action in use.

In a pavement constructed according to my invention the cork slabs not only impart resilience but add to the tensile strength of the structure and insulate the foundation and sub-soil against heat and cold. The wear course is thin enough and flexible enough to transmit the resiliency of the cork. Optionally the foundation course may be reinforced with heavy wire mesh. Furthermore, the foundation course may be made of Portland cement concrete with the cork slabs embedded in the concrete while fresh.

Herein, the employment of the terms concrete and cement without qualification as hydraulic or bituminous are to be taken as generic to compositions embodying a mineral aggregate and binder.

I claim:

1. A pavement for playing courts and the like comprising superposed courses of bituminous concrete with an interposed cushioning and insulating course of cork, the several courses bound together by a bituminous cement layer, the upper course being of composite character with the aggregate bound together in the lower and upper portions by bituminous cement and hydraulic cement respectively, the latter being in sufficient excess to provide an overlying and relatively thin wear surface of hydraulic cement.

2. A pavement for playing courts and the like comprising in superposed relationship a bituminous concrete foundation, cork slabs and a bituminous concrete Wear course, with interposed binding coats of bituminous cement, the upper voids in the bituminous concrete wear course filled with a hydraulic mortar in surplus quantity whereby to present a relatively thin wear surface of hydraulic cement.

3. A pavement for playing courts and the like comprising in superposed relationship a bituminous concrete foundation, cork slabs and a bituminous concrete wear course, with interposed binding coats of bituminous cement, the upper voids in the bituminous concrete wear course filled with a hydraulic mortar composed of cement and sand in surplus quantity whereby to present a wear surface of hydraulic, cement, the latter brushed to present a slightly roughened wear surface, the wear course divided into zones of play by intersecting strips of differently colored material resting upon the. cork course and of a thickness corresponding to that of the wear course.

4. A pavement for playing courts and the like comprising in superposed relationship a lower foundation course of bituminous concrete, an intermediate course of cork slabs and an upper wear course comprising a composite concrete in which the mineral aggregate is bound in the lower portion by bituminous cement and in the upper portion by hydraulic cement, the several courses bound together by coats of bituminous cement, and the upper wear surface brushed to present minute ridges and valleys, the wear course divided into zones of play by intersecting strips of differently colored material resting upon the cork course and of a thickness corresponding to that of the wear course.

5. A pavement for playing courts and the like comprising in superposed relationship a lower foundation course of bituminous concrete, an intermediate course of cork and an upper wear course comprising a composite concrete in which a colored mineral aggregate is bound in the lower portion by bituminous cement and in the upper portion by hydraulic cement of a contrasting color in amount not only sufficient to fill the voids but to overlie the aggregate, thus presenting a thin upper wear surface of concrete cement.

6. A pavement for playing courts and the like comprising in superposed relationship a lower foundation course of bituminous concrete, an intermediate course of cork slabs and an upper wear course comprising a composite concrete in which a colored mineral aggregate is bound in the lower portion by bituminous cement and in the upper portion by hydraulic cement of a contrasting color, the several courses bound together by coats of bituminous cement.

'7. A pavement for playing courts and the like comprising a foundation course and a wear course with an interposed cushioning and insulating course, the wear course being of composite character with the aggregate bound together in the lower and upper portions by bituminous cement and hydraulic cement respectively, the latter of a color differing from that of the aggregate whereby to produce a terrazzo effect under wear.

8. A pavement for playing courts and the like comprising in superposed relationship a bituminous concrete foundation, a cork insulating course and a bituminous concrete wear course, with interposed binding coats of bituminous cement, the upper voids in the bituminous concrete wear course filled with mortar in surplus quantity whereby to present a relatively thin wear surface, and small mineral particles embedded within the wear surface flush with the upper level 5 thereof whereby to provide secure traction.

9. A pavement for playing courts and the like comprising in superposed relationship a bituminous concrete foundation, a cork insulating course and a bituminous concrete wear course, with interposed binding coats of bituminous cement, the upper voids in the bituminous concrete wear course filled with hydraulic mortar in surplus quantity whereby to present a relatively thin wear surface of hydraulic cement, and small colored mineral particles embedded within the wear surface substantially flush with the upper level thereof whereby to provide secure traction and to present a multicolor appearance.

10. The method of producing a playing court or the like pavement which comprises laying upon a suitably drained base a bituminous concrete foundation course, applying a coating of bituminous cement, then superposing a resilient insulating course of cork or the like upon the bituminous coating while adhesive, coating the insulating course with bituminous cement, then laying a wear course of composite concrete, the voids filled in their lower portion with bituminous cement mortar and in their upper portion with hydraulic cement mortar in excess whereby to provide a wear surface of hydraulic cement as a film above the aggregate, the mortar filling the voids of the wear course being of a color different from that of the aggregate to present incident to wear a terrazzo effect.

11. A pavement for playing courts and the like comprising a lower foundation course of concrete, an upper wear course of concrete and an intermediate resilient course, the upper wear course having the mineral aggregate bound together by a surplus of cement whereby to present a relatively thin wear surface and unsupported save by the intermediate course whereby to avail of its resiliency.

12. A pavement for playing courts and the like comprising a lower foundation course of concrete, an upper Wear course of concrete and an intermediate resilient course, the upper wear course unsupported save by the intermediate course whereby to avail of its resiliency, the several courses united by an adhesive impervious to water.

JAMES F. GALLAGHER.

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