Untrafficked Full Movie In Hindi Free Download Mp4
Solveig Lichtenberg
Saturday in New York City. A perfect winter day, sunny and cold with snow blanketing every untrafficked part of the city. Three gals finished brunch, almost left their plastic purple sled under the table, and headed off to Central Park.
As part of a study that evaluates the reflective cracking performance of asphalt mixes used as overlays for rehabilitating cracked asphalt concrete pavement, 6 test sections were built and tested with heavy vehicle simulator (HVS) at Richmond Field Station of the University of California Pavement Research Center. The HVS testing lasted for about 6 years. This paper analyzes and summarizes the falling weight deflectometer (FWD) test conducted on the test sections during the whole period. The purpose of the paper is to characterize the HVS sections with FWD, compare trafficked and untrafficked stiffness change, detect aging and seasonal effects on mix stiffness, and compare the stiffness backcalculated from FWD test with that measured in the laboratory. CalBack, a backcalculation program developed for California Department of Transportation, was used. It was found that the modulus of aggregate base was generally positively correlated with the moduli of asphalt concrete and subgrade; aging of asphalt concrete was apparent in most sections. One to 3 years after HVS testing, the modulus of damaged asphalt concrete generally recovered to some extent on most sections. The moduli of asphalt concrete backcalculated from overlay sections match reasonably well with the moduli measured in the laboratory by the frequency sweep test on flexural beam specimens.
Technical Abstract: Evaluation of recent advances in tire technologies such as advanced deflection agricultural tires (Firestone IF and VF) and precision tire inflation technologies on soil compaction, traction, fuel economy and crop yield responses are important. The purpose of the study was to investigate the effects of field and transport (road) tire inflation pressure settings of row-crop agricultural tractor and planter tires on soil compaction. A randomized complete block design experiment was conducted on a loam soil at the Iowa State University farm (Boone, Iowa) for two tire inflation pressure configurations on dual front (Firestone IF 420/85R34) and dual rear (Firestone IF 480/80R50) tires of a John Deere 8310R MFWD tractor, and transport tires (Super single 445/50R22.5) on a John Deere DB60 planter. Soil compaction was measured using Stress State Transducers (SSTs) buried at 15 cm and 30 cm depths beneath the untrafficked soil surface. Following traffic by the tractor and planter, the soil cone index was measured at (a) the centerline of the path of the front and rear outer left tractor tires and the outer left planter transport tire, (b) the edge of that path of the three tires, and (c) 20 cm laterally outboard of the tire edge. Peak Octahedral Normal Stress (ONS) and the corresponding Octahedral Shear Stress (OSS) values were calculated from the SST data. The peak ONS and the corresponding OSS from the road tire inflation pressure setting were significantly greater than those for the field tire inflation pressure setting (P < 0.01). The maximum ONS was observed at the 15 cm soil depth from the road tire inflation pressure setting of the rear tractor tires (179 kPa tire inflation pressure and 25 kN load per tire). The ONS from the front tractor tires (138 kPa tire inflation pressure and 17 kN load per tire) and planter transport tires (620 kPa tire inflation pressure and 16.5 kN load per tire) were similar to one another. Cone index data also showed significant differences, comparing before and after tire passes, at the centerline of the tire path. The peak cone index values were 1.3 MPa and 1.2 MPa from the road and field tire inflation pressure settings, respectively.
An increase in BD and PR and a decrease in TP with soil depth, as observed in control plots on all slope classes in this study, is typical for soil profiles. In untrafficked forest soils, BD and PR are typically low and TP is high in the surface horizons due to large amounts of organic matter; as the organic matter content decreases with soil depth, BD and PR increase and TP decreases ([17], [13]). Further, biological activity of roots and animals can reduce BD and PR and increase TP in the upper soil, while fine soil texture, gravel content and soil structure may increase BD and PR and lower TP at lower soil depths ([18], [4], [31]). The pore volume of a medium- to fine-textured soil consists mainly of meso- and micropores that easily hold water against gravitational forces. The smaller the pore diameter, the more the adhesion of water molecules to soil colloids exceeds the force of gravitational capillarity. So in a saturated state, all pores are filled with water that cannot be compressed. Soil moisture content determines the proportion between soil compaction and plastic deformation (in the form of rutting) after the application of machine forces ([3]). Tractor traffic with its associated wheel or track slip can directly affect the soil structure and alter physical soil properties down to deeper depths. In this study, increased soil compaction occurred throughout the soil profile with associated increases in BD and PR and reduction of TP, which has also been observed previously ([18], [38], [16], [25], [30], [5], [13]). However, relative to values from different soil depths in the control plots, changes in BD, PR and TP following machine traffic were often (but not always) highest in the upper 5 cm layer and lowest in the 20 cm layer of the soil profile. Compaction effects are generally most distinct in the upper soil layer, since the exerted pressure is maximal at the soil surface and declines with increasing depth as the total pressure is spread out over a growing area ([18], [4], [31]). As soils are compacted and lose large pores after a few passes, compaction leads to higher soil strength in the upper soil layers, which prevents much further compaction of the surface layer with additional passes and shifts forces to deeper soil layers that are then increasingly compacted ([4], [31]). Overall, damage to the soil (including deeper soil layers) was modest in this study, which might be bacause the intensity of machine traffic was generally at the low end compared to other studies (e.g., [46]) and the very dry soil conditions on this site at the time of the forwarding operation were better able to resist to the mechanical soil compaction and rutting (e.g., [43], [7]).