This paper describes the development of two computer-based procedures for the design of industrial pavements subject to heavy, off-road vehicles such as forklift and straddle carriers. The procedures model the subgrade as either a Winkler or a Boussinesq material. In either case, the methodology eschews the use of the equivalent wheel load concepts that have, hithertoo, formed the basis of most design methods for industrial pavements. Rather the programs seek to model realistically the wide spectrum of axle loads and axle configurations common in industrial applications. Such modelling requires large numbers of design calculations. For this reason the programs utilise methods of aralysiswhich have been developed to yield very compact computer code so that computation may be completed rapidly. This has the added benefit that the programs can run on relatively small computers including microcomputers. The programs are suited to the design of the jointed concrete pavements and of continuous pavements such as those formed from roller compacted concrete.

Concrete parking decks are subject to several unique problems which can initiate or aggravate deterioration. These include negative-moment cracking, cold joint cracking, cracking due to embedded conduit runs, and other water related damage. This paper will deal with these problems encountered during the rehabilitation of the parking decks in a 3-story, 28-year-old garage. This structure was not maintained for its entire life, except for the installation of a waterproofing membrane on the top deck about 8 years ago. The topics covered are: 1) inspection and testing what to look for and specific test procedures; 2) causes and recommendations for the repair of some of the problems encountered.

The Long Island Rail Road (LIRR) in conjunction with New York State Department of Transportation (NYSDOT) in December 1980, completed a grade crossing eli.mination project in Long Island. To provide a solution to problems of costly track maintenance, two parallel, 1.13 mile (1.82 km) long slab tracks were constructed. Unl ike convent ional track with cross ties ancl ballast, this slab track consists of a continuously reinforced concrete slab supported on an asphalt-treated subbase and compacted subgrade to help determine adequacy of design and suitability of this type of construction for other projects, a field testing program was developed and implemented by contracting with Construction Technology Labora-t o r i e s . The paper describes advantages of slab track systems, design details, construct i on t echni ques and sequence, inst rument at i on, test results and findings.

Roller compacted concrete (RCC) for pavements combines the technologies of cement treated aggregate base, (soil cement), and portland cement concrete, to produce a rigid slab of moderately high strength capable of carrying heavy wheel loads. Aggregate should be well graded gravel or crushed rock, 100% passing the 7/8 in. (22 mm) sieve. Fine aggregate up to 14% passing the #ZOO (75 ym) sieve is acceptable. Roller compacted concrete for heavy duty pavement has been used in British Columbia since 1976. The first installation was a 4 acre (1.6 hectare) log sorting yard on Vancouver Island. Since that time ten other RCC heavy duty pavements have been built. In 1983 a coal storage area using RCC was the first project in a severe winter climate. In 1985 RCC was used for container storage areas in Houston, Texas and Tacoma, Washington. The U.S. Army Corps of Engineers built heavy duty RCC pavements to carry military vehi-cles at Fort Hood, Texas and Fort Lewis, Washington. An aircraft parking area was built at Portland, Oregon - the first use at an airport. This paper will review some of the most significant projects that have been built since 1976 and describe the construction proce ss.

Recent innovative developments in concrete pavement design methodology, material specification, construction techniques, and pavement drainage systems prompted Ontario's Ministry of Transportation and Communications to consider alternative rigid pavement designs. In order to evaluate the relative performance of several concrete pavement designs, a 15.5 km (9.7 mi) long experimental rigid pavement was constructed in 1982 incorporating four different pavement designs, three shoulder designs and two types of surface textures. A summary of the design and construction details, plus the initial performance results of an ongoing monitoring program are documented in this paper. Early performance observations indicate superior performance of the freedraining basematerials. In addition, some anomalous behaviour based on pavement cracking and roughness suggest additional areas of process control are warranted. Continuing performance verification of preliminary conclusions indicate the new designs have resulted in a significant saving in construction materials and costs plus increased durability and oerformance with a corresponding reduction in future maintenance costs.