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Volume 14, Issue 2 (7-2014)
Abstract

The resilient modulus of subgrade is an important factor in pavement design which is determined by cyclic triaxial test on cylindrical samples. Due to test complication and difficulties, other tests could be useful if there is an appropriate correlation between results. Nowadays non-destructive testing of pavement is growing in the world as they are rapid, without destruction and have precision measuring equipment. In recent years the application of LWD has been widely developed. This device evaluates pavement structure of several locations in short time with high accuracy. The main objective of this paper is to evaluate the LWD feasibility in order to estimate subgrade resilient modulus and the quality control of construction. So the in-construction road path have been chosen, then LWD field test, CBR laboratory test and finally cyclic triaxial have been done. Also the compaction percentage of each point determined to compare with LWD results. Comparing modulus obtained from LWD results to other test lead to establish models and equation which the best relation between LWD modulus and resilient modulus acquired. Also LWD result scattering is less than CBR. Moreover LWD device has enough efficiency for structural evaluation of unbound material and quality control of pavement sublayers

Volume 25, Issue 5 (9-2023)
Abstract

Biological parameters and life tables are the most appropriate criteria for measuring a population’s adaptation to environmental and dietary circumstances. The effects of temperatures 10, 14, 20, 25, 27, 30, 33, and 35℃ on biological and life table parameters of the carob moth Ectomyelois ceratoniae (Zeller) [a 10:14 hour (D: L cycle) and 65±5% RH] were experimentally studied. Based on the age-stage, two-sex life table theory, data were analyzed at different temperatures. The findings indicated that by increasing temperature, the mean incubation period of eggs, larvae, pupae, total immature development time, and adult longevity change significantly. The Adult Pre-Oviposition Periods (APOP) were 1.75, 1.93, 1.14, 1.06, 1.06, 1.09, 0.68, and 0.68 days, with Total Pre-Oviposition Period of (TPOP), 110.56, 93.82, 81.59, 42.8, 39.3, 33.96, 30, and 27.96 days at the experimental temperatures of 10, 14, 20, 25, 27, 30, 33, and 35℃, respectively. At the study temperature, the total life span was 121.22, 101.15, 88.82, 48.02, 44.55, 39.53, 34.83, and 32.73 days, respectively. The intrinsic rates of increase (r) were -0.0016 d-1 at 10℃ and 0.0085 d-1 at 30℃. The highest finite rate of population increase (λ) was 1.0086 at 30℃, and the minimum finite rate was 0.9915, at 35℃. At 35℃, the minimum mean generation Time (T) was 28.87 days. The net Reproductive rates (R0) were 0.83, 1.08, 1.1, 1.03, 1.03, 1.35, 1.02, and 0.78, at the experimental temperatures.


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