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The surface layer of military airfield pavements is prone to damage, including cracking, abrasion, and spalling. It is proposed to strengthen the pavement mortar layer by laying fiber mesh to solve these issues. In this study, three meshes of carbon fiber, aramid fiber, and basalt fiber were selected for surface reinforcement across six pavement slabs of 1.5m (length) × 1.5m (width) × 0.25m (height). The drop hammer impact test was carried out on the six pavement slabs. The test data were analyzed using impact times, crack development characteristics, and development models on the surface deflection as evaluation indices. The results show that the fiber mesh can effectively improve the impact resistance of concrete pavement slabs. Aramid fiber mesh best strengthened the pavement surface, whereas the basalt fiber mesh had the least strengthening effect. However, the mesh size has a negligible influence on the impact resistance of concrete pavement slabs. The effect of fiber mesh on improving the impact resistance of the concrete pavement slab corner was greater than that of the concrete pavement slab edge midpoint. Considering the performance and cost indicators, within the scope of the study, aramid fiber mesh is the most suitable for surface strengthening of airfield concrete pavement. [ABSTRACT FROM AUTHOR]

The frost resistance and abrasion resistance of the fiber mesh reinforced concrete under the simulated treatment of external environment were studied through the frost resistance test and abrasion test. The relative dynamic modulus, the amount of spalling per unit area, the amount of abrasion per unit area and abrasion depth were used as evaluation indexes. The result shows that the frost resistance and abrasion resistance of concrete can be enhanced by fiber mesh. For the frost resistance, enhancement effect of carbon fiber mesh is better than that of basalt fiber mesh, and better than that of aramid fiber mesh. For the abrasion resistance, enhancement effect of aramid fiber mesh is better than that of basalt fiber mesh, and better than that of carbon fiber mesh. On the whole, the frost resistance and abrasion resistance of basalt fiber mesh reinforced concrete are better. Therefore, basalt fiber mesh is recommended to strengthen the frost resistance and abrasion resistance of concrete in engineering practice.

In order to solve capability problems occurred in airport pavement slabs, a new airport concrete pavement ultra‐thin whitetopping (UTW) overlay structure was put forward on the basis of UTW theory. By modeling the structure in the FEM software ANSYS and applying loads on it, the structural critical loading position was determined, stress variation pattern at the bottom of the overlay slab was studied regarding the changes in overlay slabs' size and thickness as well as the bonding conditions between the asphalt overlay and UTW overlay. Meanwhile, the impact of the asphalt overlay on the tensile stress at bottom of the UTW overlay slab, which is strongly influenced by thickness and elastic modulus, was also explored. In order to minimize the tensile stress at the bottom of the overlay slab and prolong the lifespan of the pavement structure, the size and thickness of the UTW overlay should be strictly controlled—the size should not exceed 1.8 × 1.8 m while the thickness should be no less than 7 cm, and asphalt with elastic modulus over 1,500 MPa was recommended to be chosen as the raw material for the asphalt overlay. [ABSTRACT FROM AUTHOR]

In order to study the interlayer bond property of airport double-layer pavement, the cement concrete cube splitting tensile test and double-layer beam test were conducted. The bond mechanism of fiber grid and airport double-layer pavement was analyzed. The deflection and strain of upper and lower beams of double-layer beam were measured. The splitting tensile strength of new and old cement concrete cubes, the strain ratio, deflection difference and coupling coefficient of the double-layer beam were taken as criteria for the interlayer bond property of airport double-layer pavement. The result demonstrates that the splitting tensile strength is maximal when the basalt fiber grid with dimension of 5 mm was adopted, the old cement concrete and fiber grid surface treatment have great influence on splitting tensile strength, but the maximum grain size of coarse aggregate have few influence on it. The friction between double-layer beam reduces the strains of the bottom of the lower and upper beams by 44.44–98.46%. The fiber grid and old cement concrete surface treatment not only increase the coupling coefficient with the range of 4.60–15.73% but also decrease the deflection difference, the number of which ranges from 0.004 mm to 0.016 mm, thus improve the integral force performance and deformation ability of double-layer beams. [ABSTRACT FROM AUTHOR]

To investigate the structural response of emergency pavement repairs under aeroplane loading and verify the backfill material and structural applicability, two craters were backfilled. Crater 1 comprised a 2.4 m thick layer of recovered flying objects, 0.4 m of graded crushed rock (GCR), 0.2 m of roller-compacted concrete and a fibre-reinforced plastic (FRP) course. Crater 2 comprised a 2.4 m thick layer of flying objects, 0.6 m of GCR and a FRP course. Static and dynamic loads were applied using two aeroplanes. The results showed that the FRP pavement layer reduced the maximum deflection of crater 2 by 21%. Crater 1 and the concrete pavement were both slightly rigid structures with a strong load-transfer ability. The dynamic deflection basin curves of crater 2 could be fitted using a Gaussian function, while the curves of crater 1 and the concrete pavement were fitted using a quartic polynomial. Under static loading, the earth pressures of crater 2 at −0.6 m, −0.4 m and −0.2 m depths were 4.3, 9.0 and 9.6 times of those of crater 1, respectively. At a depth of −0.2 m, the earth pressure of crater 1 was 0.11 MPa, while that of crater 2 was 1.06 MPa. The results can be used to guide rapid quality inspection and optimisation design of emergency pavement repair structures and materials. [ABSTRACT FROM AUTHOR]