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In this paper, the dissipative energy in the damage process was employed to solve the damage variable while the damage constitutive model was established. In this model, the Mohr-Coulomb criterion and the energy dissipation theory were introduced. Considering the hardening and softening characteristics of rock during loading, the non-associated plastic flow rule was applied to describe the plastic deformation of rock, and the damage variable was calculated by quoting the dissipation energy and damage energy dissipation rate in the damage process. Based on the conventional triaxial loading-unloading experiments, the energy consumption and damage evolution law of rock was analyzed. The expression of damage energy dissipation rate was established, and the parameters in the model were calibrated. Simulation was conducted by this model and the simulation results were compared with the experimental results to validate the model. In this process, the following conclusions were obtained: (1) in the elastic stage, the damage dissipation energy increases slowly with the axial strain, showing an upward concave curve, and the growth rate reaches the maximum near the peak-stress. In the residual stage, the relationship between damage dissipation energy and axial strain is linear; (2) based on elastic modulus associated damage definition, the experimental results show that there is a damage variable limit less than 1, and the damage variable limit gradually decreases with the increase of confining pressure; (3) the model in this paper can be used to investigate the strength, hardening, softening characteristics and strain law of rock under different confining pressures during the loading process. The numerical simulation results can describe the stress-strain relationship and damage evolution law of rock.

Background: Newborn anogenital distance (AGD) has been associated with prenatal exposure of phthalates. The association between prenatal phthalate exposure and sex steroid hormones in newborns is unclear. Object: This study aimed to examine whether cord-blood sex hormone levels were associated with prenatal phthalate exposure and newborn anogenital distance (AGD). Methods: In the Taiwan Maternal and Infant Cohort Study, we recruited 1,676 pregnant women in their third trimester in 2012–2015 in Taiwan. We determined 11 urinary phthalate metabolites in pregnant women, three maternal and five cord-blood steroid sex-hormone concentrations. Five hundred and sixty-five mother-infant pairs with sufficient data were included. Trained neonatologists measured 263 newborns' AGD. We examined the associations of prenatal phthalate metabolite levels with AGD and hormones using linear regression models and evaluated correlations between maternal and cord-blood sex hormone levels and AGD. Results: Compared with the male newborns exposed to maternal phthalate metabolites at the first tertile, AGD was -3.75, -3.43, and -3.53 mm shorter among those exposed at the median tertile of di-2-ethylhexyl phthalate (DEHP) metabolites, monobenzyl phthalate (MBzP), and monomethyl phthalate (MMP), respectively. Compared with those who had exposed at the first tertile, cord-blood follicle-stimulating hormone (FSH) decreased among male newborns exposed at higher levels of MMP, mono-n-butyl phthalate (MnBP), MBzP and DEHP, and among female newborns exposed at higher levels of MMP, MBzP and mono(2-ethyl-5-hydroxyhexyl) phthalate. However, we did not observe significant correlations of maternal or cord-blood sex steroid hormones with newborns' AGDs. Conclusions: Alterations in cord-blood sex steroid hormone levels were associated with prenatal phthalate exposures, particularly in male newborns. Women aspiring to be pregnant should be alerted of the need of reducing phthalate exposure. [ABSTRACT FROM AUTHOR]