Strain-softening composite damage model of rock under thermal environment
- PDF / 1,736,371 Bytes
- 13 Pages / 595.276 x 790.866 pts Page_size
- 39 Downloads / 285 Views
ORIGINAL PAPER
Strain-softening composite damage model of rock under thermal environment Wen-lin Feng 1 & Chun-sheng Qiao 1 & Tan Wang 2 & Ming-yuan Yu 1 & Shuang-jian Niu 3 & Zi-qi Jia 4 Received: 28 July 2019 / Accepted: 10 April 2020 # Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract To ensure the safe and effective application of deep geotechnical engineering, it is necessary to establish a suitable constitutive model of the rocks in thermal environment, including geothermal energy mining, and deep geological treatment of nuclear waste and tunnel fire. A strain-softening damage model of the rocks with defect growth is established based on damage evolution. According to the change in the tangent modulus from the compression phase to the elastic stage, we established a constitutive model reflecting the nonlinearity characteristics of the compression phase. According to the change in the energy conversion, the energy consumption coefficient is introduced to describe the deformation characteristics of the rocks when the residual stress is reached. The specific physical meaning and the calculation method of the energy consumption coefficient are given to correct the shortcomings of the evolution of the damage variable. We then analyzed the relationship between parameters in the constitutive model of the rocks at high temperature and normal temperature. Based on the constitutive model of the rocks at normal temperature, we established a constitutive model reflecting the influence of high temperature. Finally, the established model fit the stress-strain curves of several kinds of the rocks at different temperatures and generated desired results. The established model can be used to describe the stress-strain curve characteristics of the rocks at different temperatures. Keywords Strain-softening model . Compression nonlinearity . Tangent modulus . Residual stress . Damage evolution
Introduction Rocks, as an important element of the earth’s composition, are subject to environmental changes. The mechanical properties of the rocks vary with the change in the surrounding environment (Makedon and Chatzigogos 2012; Lu et al. 2017; Giacomo et al. 2017; Zhao et al. 2019). A large number of rock slopes and underground cavern excavation projects show
* Wen-lin Feng [email protected] 1
School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China
2
School of Civil Engineering, University of Birmingham, Birmingham B15 2TT, UK
3
School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454003, China
4
No. 10 Pingdingshan Tianan Coal Industry Co., Ltd., China Pingmei Shenma Energy and Chemical Industry Group Co., Ltd., Pingdingshan 467000, China
that the mechanical properties of the rocks are particularly important for the safety design and the stability analysis of the geotechnical structures (Mostafa et al. 2010; Tian et al. 2016). Therefore, establishing rock mechanics constitutive model to characterize its deformation characteristics has always been one of
Data Loading...
