木材作为一种天然的非均质材料,在荷载作用下同一纹理方向会表现出拉、压性能不对称的现象。为了更好地描述拉压性能不同的木材非线性力学行为,在一种用于描述木材受压的双参数本构模型的基础之上,通过引入Drucker-Prager塑性理论的静...木材作为一种天然的非均质材料,在荷载作用下同一纹理方向会表现出拉、压性能不对称的现象。为了更好地描述拉压性能不同的木材非线性力学行为,在一种用于描述木材受压的双参数本构模型的基础之上,通过引入Drucker-Prager塑性理论的静水压概念,建立了能够描述拉压性能不同的木材非线性统一本构模型。实验验证结果表明:模型描述的应力–应变曲线与实验结果吻合较好,运用本文中所建立的本构模型能够很好地描述木材在载荷作用下的非线性力学行为,而且考虑了木材同一纹理方向拉伸和压缩性能的差异。As a natural heterogeneous material, wood exhibits asymmetric tensile and compressive properties in the same texture direction under load. In order to better describe the nonlinear mechanical behavior of wood with different tensile and compressive properties, based on a two parameter constitutive model used to describe wood under compression, a nonlinear unified constitutive model of wood that can describe different tensile and compressive properties was established by introducing the concept of hydrostatic pressure from Drucker Prager plasticity theory. The experimental verification results show that the stress-strain curve described by the model is in good agreement with the experimental results. The constitutive model established in this paper can well describe the nonlinear mechanical behavior of wood under load, and consider the differences in tensile and compressive properties of wood in the same texture direction.展开更多
设{εt,t∈Z}为定义在同一概率空间(Ω,F,P)上的严平稳随机变量序列,满足Eε0=0,E|ε_0|~p<∞,对某个p>2,且满足强混合条件.{a_j,j∈Z}为一实数序列,满足sum from -∞ to ∞(|a_j|)<∞,sum from -∞ to ∞(a_j)≠0.令X_t=sum f...设{εt,t∈Z}为定义在同一概率空间(Ω,F,P)上的严平稳随机变量序列,满足Eε0=0,E|ε_0|~p<∞,对某个p>2,且满足强混合条件.{a_j,j∈Z}为一实数序列,满足sum from -∞ to ∞(|a_j|)<∞,sum from -∞ to ∞(a_j)≠0.令X_t=sum from -∞ to ∞(a_jε_(t-j))(t≥1),S_n=sum from 1 to n(X_t)(n≥1).利用由强混合序列生成的线性过程的弱收敛定理及矩不等式讨论了在bn=O(1/loglogn)的条件下,当∈→0时,P{|S_n|≥(∈+b_n)τ(2nloglogn)^(1/2)}的一类加权级数的收敛性质.展开更多
文摘木材作为一种天然的非均质材料,在荷载作用下同一纹理方向会表现出拉、压性能不对称的现象。为了更好地描述拉压性能不同的木材非线性力学行为,在一种用于描述木材受压的双参数本构模型的基础之上,通过引入Drucker-Prager塑性理论的静水压概念,建立了能够描述拉压性能不同的木材非线性统一本构模型。实验验证结果表明:模型描述的应力–应变曲线与实验结果吻合较好,运用本文中所建立的本构模型能够很好地描述木材在载荷作用下的非线性力学行为,而且考虑了木材同一纹理方向拉伸和压缩性能的差异。As a natural heterogeneous material, wood exhibits asymmetric tensile and compressive properties in the same texture direction under load. In order to better describe the nonlinear mechanical behavior of wood with different tensile and compressive properties, based on a two parameter constitutive model used to describe wood under compression, a nonlinear unified constitutive model of wood that can describe different tensile and compressive properties was established by introducing the concept of hydrostatic pressure from Drucker Prager plasticity theory. The experimental verification results show that the stress-strain curve described by the model is in good agreement with the experimental results. The constitutive model established in this paper can well describe the nonlinear mechanical behavior of wood under load, and consider the differences in tensile and compressive properties of wood in the same texture direction.
文摘设{εt,t∈Z}为定义在同一概率空间(Ω,F,P)上的严平稳随机变量序列,满足Eε0=0,E|ε_0|~p<∞,对某个p>2,且满足强混合条件.{a_j,j∈Z}为一实数序列,满足sum from -∞ to ∞(|a_j|)<∞,sum from -∞ to ∞(a_j)≠0.令X_t=sum from -∞ to ∞(a_jε_(t-j))(t≥1),S_n=sum from 1 to n(X_t)(n≥1).利用由强混合序列生成的线性过程的弱收敛定理及矩不等式讨论了在bn=O(1/loglogn)的条件下,当∈→0时,P{|S_n|≥(∈+b_n)τ(2nloglogn)^(1/2)}的一类加权级数的收敛性质.
