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This report describes the demonstration of technologies and procedures developed during April 2002 and May 2004 under the Joint Rapid Airfield Construction (JRAC) Program. The demonstration took place at Sicily Landing Zone (LZ) at Fort Bragg, NC, in July of 2004. The objective of the exercise was to demonstrate the procedures and technologies developed under the JRAC Program by rapidly building two parking aprons capable of supporting C-130 transport aircraft taxiing and parking operations. The exercise was conducted under continuous 24-hr operations to simulate a real-world rapid construction environment. Apron 1 (north apron) was constructed using two technologies, one-half being ACE™ Matting and the other half being a cement-polymer stabilized soil surface. Apron 2 (south apron) was constructed solely of a fiber-cement-stabilized soil system. Both aprons were treated with a polymer emulsion surface application to form a sealed surface against abrasion and water infiltration. The entire construction of both aprons required 76 hr, with Apron 1 finished in 48 hr. The construction of Apron 1 was validated by operation of a C-130 aircraft approximately 31 hr after completion with success and high praises from the aircraft flight crew on the stability and surface of the apron, as well as its dust-abating characteristics.

Matting systems are used for temporary applications on soft soils to reduce ground pressure exerted by aircraft, heavy equipment, vehicles, and construction material. They have been used for military airfields, construction platforms, and similar applications. Previous evaluation studies of matting systems have typically consisted of full-scale testing, with only a limited amount of numerical modeling found in the literature. This paper presents results of full-scale accelerated testing of 21 test sections encompassing five matting systems, five soil-support conditions, and two aircraft loadings. One of the soil-support conditions was instrumented and tested in conjunction with three matting systems and one aircraft loading. Three-dimensional finite-element modeling was performed on the instrumented sections using the measured test data for calibration. Good matches of measured soil stresses were obtained with the model for two of the mats, whereas the model underpredicted stresses in the third mat. Modeling of the type performed in this paper was capable of correctly ranking the performance of the matting systems modeled relative to the full-scale test results.

The density of soil is crucial in engineering, construction, and research. Standard methods to determine density use procedures, equipment or expendable materials that limit their effectiveness in challenging field conditions. Some methods require burdensome logistics or have time requirements that limit their use or the number of tests that can be executed. A test method, similar to the sand-cone method, was developed that uses steel shot as the material to which a volume of soil is compared to calculate soil density. Steel shot is easily recovered and reused, eliminating the need for specialty sand and calibrated cones or containers, and allows rapid determination of the volume of displaced soil. Excavated soil also provides measurements of total mass and moisture content. Volume, mass, and moisture content are applied in simple calculations to determine wet and dry densities and unit weight of the soil. Proficiency in performing the test can be achieved with minimal training, and the required kit can be assembled for a reasonable cost. Field uses of the method in dry environments in a variety of soil types demonstrated that the method can produce repeatable results within 2% of the values of soil density determined by traditional methods, with advantages in logistics.

The focus of this work was to evaluate the use of commercially available matting systems to sustain C-130 and C-17 transport aircraft loads over soil bases having different California bearing ratio (CBR) ranges. Test sections were constructed using three range of CBR: high (CBR=40–50), medium (CBR=8–10), and low (CBR=5–6). Testing began with the C-130 load cart and six different matting systems. The C-130 was the lesser of the two aircraft loads examined and this initial testing was used as an "elimination round" for the various matting systems chosen. Matting systems deemed suitable for the C-130 were further tested under the C-17 load cart. Systems were evaluated based on logistical and assembly requirements, mat damage sustained during traffic, and accumulated deformation of the mats and soil during traffic. The latter are shown in line plots of passes versus plastic rut formation. Summary information on each matting system tested and the test sections themselves is presented. Conclusions on the matting systems tested and their application are discussed.