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In this article, an attempt has been made to estimate the Modelling Error (ME) associated with compression capacity models available in international standards for different failure modes of compression members fabricated from Cold-Formed Steel (CFS) lipped channel sections. For the first time, a database has been created using test results available in the literature for compression capacities of CFS lipped-channel sections. e database contains details of 273 numbers of compression member tests which have failed in different failure modes, namely, (i) flexural, torsional, flexural-torsional, local, and distortion buckling and (ii) failure by yielding. Only those sources, which report all the details, required to compute the capacities using different standards are included in the database. e results of experimental investigations carried out at CSIR-Structural Engineering Research Centre, Chennai, are also included in this test database. e international codes of practice used in calculation of compression capacities of the database columns considered in this paper are ASCE 10-15 (2015), AISI S100-16 (2016), AS/NZS 4600: 20184600: (20184600: ), and EN 19934600: -1-3:20064600: (2006. e ASCE, AISI, AS/NZS, and EN design standards have different design guidelines with respect to the failure modes, e.g., ASCE 10-15 (2015) standard provides stringent criteria for maximum width to thickness ratio for stiffened and unstiffened elements. Hence, guidelines for the distortional buckling mode are not provided, whereas the AISI S100-16 (2016) and AS/NZS 4600: 2018 (2018) standards consider separate guidelines for distortional buckling mode and EN 1993EN -1-3:2006EN (2006 standard considers combined local and distortional buckling mode. Further, the sample size for each design standard is varying depending on the design criteria and failure mode. Studies on statistical analysis of ME suggest that the compression capacity predicting models for flexural-torsional buckling mode are associated with large variation irrespective of the design standard. Similar observations are made for the flexural buckling model as per EN 1993EN -1-3:2006EN (2018 standard and distortional buckling models as per AISI S100-16 (2016) and AS/NZS 4600: 2018 (2018) standards. e compression capacities for test database sections are evaluated by neglecting the partial safety factors available in design standards. e probabilistic analysis to determine statistical characteristics of compression capacity indicates the importance of consideration of ME as a random variable. Hence, the ME results will be useful in code calibration studies and may have potential reference to design practice.

A study describes the use of natural ( 210 Pb) and anthropogenic ( 137 Cs) radiometric dating techniques to determine sedimentation rates and life of Kodaikanal Lake. The core sediment from 46 cm was collected and analyzed for 210 Pb and 137 Cs using an Alpha spectrometer 7200-04 and a Gamma-ray spectrometer GC-3520.Bathymetry studies aided in the selection of a representative sample location and the measurement of the lake's underwater depth, with maximum and mean depths of 11 and 3.38 m, respectively. The maximum and minimum dry bulk density ranged from 0.57 to 1.05 g/cm 3 (mean of 0.73 g/cm 3 ), and the weight percentage of porosity collected sediment sample ranged from 60.33 to 78.63 wt. % (mean of 72.32 wt. % ). This study determined the sediment grain size as well as the percentages of sand, silt, and clay. The findings indicate that the core sediment samples contain 56.05 to 69.62 wt.% (mean of 63.21 wt.%) sand, 28.03 to 41.71 wt.% (mean of 34.55 wt.%) silt, and 1.81 to 3.98 wt.% (mean of 2.34 wt.%) clay. For geochronology studies in core sediments, the 210 Pb technique was used to assess a model of time changes in the deposit. The sedimentation rate depended on the consistent rate supply (CRS) of the 210 Pb model. The 210 Pb model was confirmed using 137 Cs radioactivity released into the global fallout after nuclear testing (1963) and the Chernobyl accident (1986). The depth concentration of 210 Pb ranged from 3.89 ± 0.1 to 15.4 ± 1.6 Bq/kg with a mean of 210 Pb concentration is 7.23 ± 0.86 Bq/ kg. The 137 Cs radioactivity was varied from the upper and lower peaks that appeared clearly at depths of 16 and 29 cm, respectively, with successive phases of 18.68 ± 1.36 and 22.04 ± 1.4 Bq/kg. According to the CRS model, the mean sedimentation rate was 0.51 ± 0.14 cm/year, and the core age was 86 years. The 137 Cs have likely been the mean sedimentation rate of 0.535 ± 0.07 cm/year and 83 years. The evaluated life of Kodaikanal Lake as an average of 210 Pb and 137 Cs sedimentation rate since 1933 is about 650 ± 24 years and 582.75 ± 19 years.

This current research aims to perceive depositional energy environment of jagatsinghpur coastal area sediments with outcome of Textural aspects of particle size dissemination and Magnetic susceptibility (MS). In study, 36 sediment samples recovered from 12 locations with 3 points such as Low Tide (LT), High Tide (HT), and Berm (BM) along with every 5 km interval. To observe outcome from different parameters such as Mean (MQ), Standard deviation (SD), Skewness (SK) & Kurtosis (KU), bivariate plots, and MS methods were adopted. From the outcome, the MQ and SD of LT, HT and BM infer medium sand to fine sand with a moderately sorted to well-sorted nature as well as SK and KU of LT, HT and BM infer extreme coarser skewed to fine skewed with platykurtic to extreme leptokurtic nature. Textural parameters shows the Southern Part of the study area experienced the low energy condition. Mainly, the energy process plot indicates sediments fall in the inner shelf and river environment. CM plot expressed the sediment samples reacted as graded suspension and rolling mechanism. The MS of low frequency, the higher quantity of magnetic contents of 3 zones low tide (LT), high tide (HT), and berm (BM) has been 62.57 x10− 8 m3 kg− 3, 72.83 x10− 8 m3 kg− 3 and 454.63 x10− 8 m3 kg− 3. The Pearson’s Correlation signifies the + ve relationship between Berm low frequency vs Berm Mean, low tide means (r2 = 0.57, (r2 = 0.40) signifies the multi-source of sediment deposition. From the output, the northern part of study infers high energy environment.

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