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Continuous Dependence of Bounded Φ-variation Solutions on Parameter for a Class of Discontinuous Systems 被引量:2
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作者 马学敏 李宝麟 林长伟 《Chinese Quarterly Journal of Mathematics》 2015年第4期610-619,共10页
The functions of bounded φ-variation are development and generalization of bounded variation functions in the usual sense.Henstock-Kurzweil integral is a very useful tool for some discontinuous systems. In this paper... The functions of bounded φ-variation are development and generalization of bounded variation functions in the usual sense.Henstock-Kurzweil integral is a very useful tool for some discontinuous systems. In this paper, by using Henstock-Kurzweil integral, we establish theorems of continuous dependence of bounded D-variation solutions on parameter for a class of discontinuous systems on the base of D-function. These results are essential generalizations of continuous dependence of bounded variation solutions on parameter for the systems. 展开更多
关键词 discontinuous systems Henstock-Kurzweil integral bounded φ-variation solution continuous dependence
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Bounded and Unbounded Solutions of the SD Oscillator at Resonance
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作者 Bian Jingke Liu Jie 《数学理论与应用》 2024年第4期45-69,共25页
In this paper we study the boundedness and unboundedness of the solutions of the smooth and discontinuous(SD)oscillatorbegin{equation*}x''+f(x)x'+x-frac{x}{sqrt{x^{2}+alpha^{2}}}=p(t).end{equation*}Since f... In this paper we study the boundedness and unboundedness of the solutions of the smooth and discontinuous(SD)oscillatorbegin{equation*}x''+f(x)x'+x-frac{x}{sqrt{x^{2}+alpha^{2}}}=p(t).end{equation*}Since f(x)≠0,the system is non-Hamiltonian,so we have to introduce some reversibility assumptions to apply a suitable twist theorem,for reversible maps with small twist.Moreover,when the nonnegative parameterαdecreases to 0,the system becomes discontinuous.In this case,we need to introduce some suitable transformations to overcome the lack of regularity.We will prove that for any nonnegative parameterα,when p(t)is an odd periodic function satisfying∣∣∫2π0p(t)sintdift∣∣<4,all the solutions are bounded;when p(t)satisfies∣∣∫2π0p(t)sintdift∣∣>4,the SD oscillator has unbounded solutions,and when p(t)satisfies∣∣∫_(0)^(2π)p(t)sintdift∣∣≥4+|F|_(∞),all the solutions are unbounded. 展开更多
关键词 SD oscillator Reversible system bounded solution Unbounded solution
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Globally Bounded Solutions in A Chemotaxis Model of Quasilinear Parabolic Type 被引量:1
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作者 LIU Bing-chen DONG Meng-zhen 《Chinese Quarterly Journal of Mathematics》 2019年第3期274-282,共9页
In this paper,we consider a quasilinear parabolic-parabolic chemotaxis model with nonlinear diffusivity,aggregation and logistic damping source:■where k1 epu≤D(u) or k1 up≤D(u);k2 equ≤S(u)≤k3 equ;g(u)≤a-... In this paper,we consider a quasilinear parabolic-parabolic chemotaxis model with nonlinear diffusivity,aggregation and logistic damping source:■where k1 epu≤D(u) or k1 up≤D(u);k2 equ≤S(u)≤k3 equ;g(u)≤a-beku.It is proved that,if q <k-1 or q=k-1 and b> b0 for some constant b0> 0,then there exists a unique classical solution which is globally bounded.The results show the effect of the aggregation and the logistic damping source on the existence of globally bounded solutions. 展开更多
关键词 CHEMOTAXIS Nonlinear DIFFUSIVITY AGGREGATION LOGISTIC Type Damping Globally bounded solution
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BOUNDED TRAVELING WAVE SOLUTIONS OF VARIANT BOUSSINESQ EQUATION WITH A DISSIPATION TERM AND DISSIPATION EFFECT
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作者 张卫国 刘强 +1 位作者 李正明 李想 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期941-959,共19页
This article studies bounded traveling wave solutions of variant Boussinesq equation with a dissipation term and dissipation effect on them. Firstly, we make qualitative analysis to the bounded traveling wave solution... This article studies bounded traveling wave solutions of variant Boussinesq equation with a dissipation term and dissipation effect on them. Firstly, we make qualitative analysis to the bounded traveling wave solutions for the above equation by the theory and method of planar dynamical systems, and obtain their existent conditions, number, and general shape. Secondly, we investigate the dissipation effect on the shape evolution of bounded traveling wave solutions. We find out a critical value r^* which can characterize the scale of dissipation effect, and prove that the bounded traveling wave solutions appear as kink profile waves if |r|≥ r^*; while they appear as damped oscillatory waves if |r| 〈 r^*. We also obtain kink profile solitary wave solutions with and without dissipation effect. On the basis of the above discussion, we sensibly design the structure of the approximate damped oscillatory solutions according to the orbits evolution relation corresponding to the component u(ξ) in the global phase portraits, and then obtain the approximate solutions (u(ξ), H(ξ)). Furthermore, by using homogenization principle, we give their error estimates by establishing the integral equation which reflects the relation between exact and approximate solutions. Finally, we discuss the dissipation effect on the amplitude, frequency, and energy decay of the bounded traveling wave solutions. 展开更多
关键词 Variant Boussinesq equation with dissipation term shape analysis bounded traveling wave solution error estimate dissipation effect
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Boundedness of Solutions for Elliptic Variational Inequalities
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作者 Ye Ruifen(Department of Mathematics, Guangzhou Teachers’ College, 510400) 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第1期56-62,共7页
The boundedness is proved under more general structural conditions to solutions of elliptic variational inequalities and a priori estimates are obtained to maximum modulus of solutions for some special cases.
关键词 elliptic variational inequality generalized solution bounded solution:maximum modulus priori estimate
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The Estimation for Lower Bounds of the Solutions of Fermat's Equation
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作者 乐茂华 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期52-55,共4页
Let p be a prime with p≡3(mod 4). In this paper,by using some results relate the representation of integers by primitive binary quadratic forms,we prove that if x,y,z are positive integers satisfying x^p+y^p=z^p, p|x... Let p be a prime with p≡3(mod 4). In this paper,by using some results relate the representation of integers by primitive binary quadratic forms,we prove that if x,y,z are positive integers satisfying x^p+y^p=z^p, p|xyz, x<y<z, then y>p^(6p-2)/2. 展开更多
关键词 Fermat's last theorem integer solution lower bound
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THE LIMITING PROFILE OF SOLUTIONS FOR SEMILINEAR ELLIPTIC SYSTEMS WITH A SHRINKING SELF-FOCUSING CORE
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作者 金可 石影 谢华飞 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期583-608,共26页
In this paper,we consider the semilinear elliptic equation systems{△u+u=αQ_(n)(x)|u|^(α-2)|v|^(β)u in R^(N),-△v+v=βQ(x)|u|^(α)|v|^(β-2)v in R^(N),where N≥3,α,β>1,α+β<2^(*),2^(*)=2N/N-2 and Q_(n) are... In this paper,we consider the semilinear elliptic equation systems{△u+u=αQ_(n)(x)|u|^(α-2)|v|^(β)u in R^(N),-△v+v=βQ(x)|u|^(α)|v|^(β-2)v in R^(N),where N≥3,α,β>1,α+β<2^(*),2^(*)=2N/N-2 and Q_(n) are bounded given functions whose self-focusing cores{x∈R^(N)|Q_(n)(x)>0} shrink to a set with finitely many points as n→∞.Motivated by the work of Fang and Wang[13],we use variational methods to study the limiting profile of ground state solutions which are concentrated at one point of the set with finitely many points,and we build the localized concentrated bound state solutions for the above equation systems. 展开更多
关键词 Schrödinger system ground states solutions bound state solutions
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Recrystallization of freezable bound water in aqueous solutions of medium concentrations
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作者 赵立山 潘礼庆 +2 位作者 纪爱玲 曹则贤 王强 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期294-298,共5页
For aqueous solutions with freezable bound water, vitrification and recrystallization are mingled, which brings difficulty to application and misleads the interpretation of relevant experiments. Here, we report a quan... For aqueous solutions with freezable bound water, vitrification and recrystallization are mingled, which brings difficulty to application and misleads the interpretation of relevant experiments. Here, we report a quantification scheme for the freezable bound water based on the water-content dependence of glass transition temperature, by which also the concentration range for the solutions that may undergo recrystallization finds a clear definition. Furthermore, we find that depending on the amount of the freezable bound water, different temperature protocols should be devised to achieve a complete recrystallization. Our results may be helpful for understanding the dynamics of supercooled aqueous solutions and for improving their manipulation in various industries. 展开更多
关键词 recrystallization aqueous solution glass transition freezable bound water
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REMARKS ON BOUNDS ON THE DISCREPANCY OF APPROXIMATE SOLUTIONS CONSTRUCTED BY GODUNOV'S SCHEME
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作者 王靖华 《Acta Mathematica Scientia》 SCIE CSCD 1989年第4期437-452,共16页
The bounds on the discrepancy of approximate solutions constructed by Gedunov's scheme to IVP of isentropic equations of gas dynamics are obtained, Three well-knowu results obtained by Lax for shock waves with sma... The bounds on the discrepancy of approximate solutions constructed by Gedunov's scheme to IVP of isentropic equations of gas dynamics are obtained, Three well-knowu results obtained by Lax for shock waves with small jumps for general quasilinear hyperbolic systems of conservation laws are extended to shock waves for isentropic equations of gas dynamics in a bounded invariant region with ρ=0 as one of boundries of the region. Two counterexamples are given to show that two iuequalities given by Godunov do not hold for all rational numbers γ∈(1, 3]. It seems that the approach by Godunov to obtain the forementioned bounds may not be possible. 展开更多
关键词 TE REMARKS ON boundS ON THE DISCREPANCY OF APPROXIMATE solutionS CONSTRUCTED BY GODUNOV’S SCHEME
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SIGN-CHANGING SOLUTIONS FOR SCHRDINGER EQUATIONS WITH VANISHING AND SIGN-CHANGING POTENTIALS 被引量:2
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作者 吴元泽 黄毅生 刘增 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期691-702,共12页
In this article, we study the existence of sign-changing solutions for the following SchrSdinger equation -△u + λV(x)u = K(x)|u|^p-2u x∈R^N, u→0 as |x|→ +∞, 2N where N ≥ 3, λ〉 0 is a parameter, 2 〈... In this article, we study the existence of sign-changing solutions for the following SchrSdinger equation -△u + λV(x)u = K(x)|u|^p-2u x∈R^N, u→0 as |x|→ +∞, 2N where N ≥ 3, λ〉 0 is a parameter, 2 〈 p 〈 2N/N-2, and the potentials V(x) and K(x) satisfy some suitable conditions. By using the method based on invariant sets of the descending flow, we obtain the existence of a positive ground state solution and a ground state sign-changing solution of the above equation for small λ, which is a complement of the results obtained by Wang and Zhou in [J. Math. Phys. 52, 113704, 2011]. 展开更多
关键词 Variational methods bounded state solutions sign-changing solutions
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Anti-periodic traveling wave solution to a forced two-dimensional generalized KdV-Burgers equation 被引量:1
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作者 谈骏渝 《Journal of Chongqing University》 CAS 2003年第2期97-100,共4页
The anti-periodic traveling wave solutions to a forced two-dimensional generalized KdV-Burgers equation are studied. Some theorems concerning the boundness, existence and uniqueness of the solution to this equation ar... The anti-periodic traveling wave solutions to a forced two-dimensional generalized KdV-Burgers equation are studied. Some theorems concerning the boundness, existence and uniqueness of the solution to this equation are proved. 展开更多
关键词 KdV-Burgers equation anti-periodic traveling wave solution boundness existence and uniqueness
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ON GLOBAL BEHAVIOR OF WEAK SOLUTIONS OF COMPRESSIBLE FLOWS OF NEMATIC LIQUID CRYSTALS
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作者 王伟伟 《Acta Mathematica Scientia》 SCIE CSCD 2015年第3期650-672,共23页
In this article, we investigate the global behavior of weak solutions of a simplified Ericksen-Leslie system for compressible flows of nematic liquid crystals in time in a bounded three-dimension domain-arbitrary forc... In this article, we investigate the global behavior of weak solutions of a simplified Ericksen-Leslie system for compressible flows of nematic liquid crystals in time in a bounded three-dimension domain-arbitrary forces. By adapting the arguments for the compressible Navier-Stokes equations, and carefully analyzing the direction field of liquid crystals in the equations of angular momentum, we show the existence of bounded absorbing sets, global bounded trajectories, and global attractors to weak solutions of compressible flows of nematic liquid crystals with the adiabatic constant γ〉5/3. 展开更多
关键词 Liquid crystals weak solutions bounded absorbing set bounded trajectories ATTRACTOR
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PERIODIC SOLUTIONS OF LINEAR NEUTRAL INTEGRO-DIFFERENTIAL EQUATIONS
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作者 马世旺 王志成 许强 《Acta Mathematica Scientia》 SCIE CSCD 2004年第3期337-348,共12页
Consider the linear neutral FDEd/dt[x(t) + Ax(t - r)] = R [dL(s)]x(t + s) + f(t)where x and / are ra-dimensional vectors; A is an n x n constant matrix and L(s) is an n x n matrix function with bounded total variation... Consider the linear neutral FDEd/dt[x(t) + Ax(t - r)] = R [dL(s)]x(t + s) + f(t)where x and / are ra-dimensional vectors; A is an n x n constant matrix and L(s) is an n x n matrix function with bounded total variation. Some necessary and sufficient conditions are given which guarantee the existence and uniqueness of periodic solutions to the above equation. 展开更多
关键词 Linear neutral FDE bounded total variation periodic solution
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Solution of the Dirac equation with the ring-shaped oscillator potential
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作者 张爱萍 《Journal of Chongqing University》 CAS 2008年第2期141-144,共4页
The ring-shaped oscillator potential, obtained by replacing the Coulomb part of the Hartmann potential by a harmonic oscillator term, was investigated. Under the equal vector potential and scalar potential, the Dirac ... The ring-shaped oscillator potential, obtained by replacing the Coulomb part of the Hartmann potential by a harmonic oscillator term, was investigated. Under the equal vector potential and scalar potential, the Dirac equation was solved in spherical coordinate. The exact energy spectrum of the bound states was presented as a solution to the confluent hypergeometric equation by boundary conditions. Furthermore, the normalized angular and radial wave functions were presented. 展开更多
关键词 ring-shaped oscillator bound solution Dirac equation confluent hypergeometric function
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Branch and Bound Algorithm for Globally Solving Minimax Linear Fractional Programming
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作者 WANG Hui-man SHEN Pei-ping LIANG Yu-xin 《Chinese Quarterly Journal of Mathematics》 2024年第4期388-398,共11页
In this paper,we study the minimax linear fractional programming problem on a non-empty bounded set,called problem(MLFP),and we design a branch and bound algorithm to find a globally optimal solution of(MLFP).Firstly,... In this paper,we study the minimax linear fractional programming problem on a non-empty bounded set,called problem(MLFP),and we design a branch and bound algorithm to find a globally optimal solution of(MLFP).Firstly,we convert the problem(MLFP)to a problem(EP2)that is equivalent to it.Secondly,by applying the convex relaxation technique to problem(EP2),a convex quadratic relaxation problem(CQRP)is obtained.Then,the overall framework of the algorithm is given and its convergence is proved,the worst-case iteration number is also estimated.Finally,experimental data are listed to illustrate the effectiveness of the algorithm. 展开更多
关键词 Minimax linear fractional programming Global optimal solution Branch and bound
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基于下限模型的临界滑动面理论与数值解法
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作者 郑颖人 张金良 +4 位作者 尹德文 邵颖 苏凯 吴昊 张智沛 《岩土工程学报》 北大核心 2025年第2期438-442,共5页
临界滑动面对岩土工程的加固处理有着重要意义。目前对于临界滑动面的研究多采用上限法,基于下限定理或下限模型的临界滑动面理论与数值解法目前尚未见到。在下限模型的基础上,提出了基于下限模型的临界滑动面理论,给出了相应的数值解法... 临界滑动面对岩土工程的加固处理有着重要意义。目前对于临界滑动面的研究多采用上限法,基于下限定理或下限模型的临界滑动面理论与数值解法目前尚未见到。在下限模型的基础上,提出了基于下限模型的临界滑动面理论,给出了相应的数值解法;并以黏性土体直立边坡的临界高度问题为例,验证了临界滑动面理论与数值解法的适用性。 展开更多
关键词 下限模型 临界滑动面 数值解法
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拟线性薛定谔方程组在有界区域上的正规化解
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作者 张倩 《数学物理学报(A辑)》 北大核心 2025年第1期1-30,共30页
该文关注以下非线性耦合方程组{−Δu_(1)+ω_(1)u_(1)−1/2Δ(u_(1)^(2))u_(1)=μ_(1)|u_(1)|^(p−1)u_(1)+β|u_(2)|p+1/2|u_(1)|p−3/2u_(1),−Δu_(2)+ω_(2)u_(2)−1/2Δ(u_(2)^(2))u_(2)=μ_(2)|u_(2)|^(p−1)u_(2)+β|u_(1)|p+1/2|u_(2)... 该文关注以下非线性耦合方程组{−Δu_(1)+ω_(1)u_(1)−1/2Δ(u_(1)^(2))u_(1)=μ_(1)|u_(1)|^(p−1)u_(1)+β|u_(2)|p+1/2|u_(1)|p−3/2u_(1),−Δu_(2)+ω_(2)u_(2)−1/2Δ(u_(2)^(2))u_(2)=μ_(2)|u_(2)|^(p−1)u_(2)+β|u_(1)|p+1/2|u_(2)|p−3/2u_(2),∫_(Ω)|u_(i)|^(2) dx=ρ_(i),i=1,2,(u_(1),u_(2))∈H_(0)^(1)(Ω;R^(2))以及线性耦合方程组{−Δu_(1)+ω_(1)u_(1)−1/2Δ(u_(1)^(2))u_(1)=μ_(1)|u_(1)|^(p−1)u_(1)+βu_(2),−Δu_(2)+ω_(2)u_(2)−1/2Δ(u_(2)^(2))u_(2)=μ_(2)|u_(2)|^(p−1)u_(2)+βu_(1),∫_(Ω)|u_(i)|^(2) dx=ρ_(i),i=1,2,(u_(1),u_(2))∈H_(0)^(1)(Ω;R^(2))其中Ω⊂R^(N)(N≥1)是一个有界光滑区域,ω_(i),β∈R,μ_(i),ρ_(i)>0,i=1,2.而且,若p>1,N=1,2且若1<p≤3N+2/N-2,N≥3.应用变量替换,一方面,证明了非线性耦合方程组正规化解的存在性和轨道稳定性,以及当β→−∞时正规化解的极限行为.另一方面,应用极小化约束方法来获得线性耦合方程组的正规化解的存在性.与之前的一些结果相比,将现有结果扩展到了拟线性薛定谔方程组,并获得了线性耦合情形下的正规化解. 展开更多
关键词 线性与非线性耦合 有界区域 变量替换 正规化解 极限行为
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求解一类线性多乘积规划问题的自适应分支定界算法
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作者 梁雨欣 申培萍 尹建菲 《应用数学》 北大核心 2025年第1期217-223,共7页
本文针对一类线性多乘积规划问题(LMP)提出一种具有自适应分支规则的分支定界算法.首先将问题(LMP)转化为等价问题,然后利用分段线性近似逼近其非凸约束的凹部分,通过所提出的自适应分支规则分割盒子并迭代细化分段线性近似,将问题(LMP... 本文针对一类线性多乘积规划问题(LMP)提出一种具有自适应分支规则的分支定界算法.首先将问题(LMP)转化为等价问题,然后利用分段线性近似逼近其非凸约束的凹部分,通过所提出的自适应分支规则分割盒子并迭代细化分段线性近似,将问题(LMP)的求解过程转化为求解一系列二阶锥松弛问题(SOCR).此外,证明算法的收敛性和复杂度.最后,数值结果表明了该算法的有效性和可行性. 展开更多
关键词 线性多乘积规划 全局最优解 自适应分支定界 二阶锥松弛
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考虑底部塑性区的深埋隧洞围岩压力上限解 被引量:1
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作者 傅鹤林 易海东 +1 位作者 胡凯巽 李鲒 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第7期2625-2634,共10页
基于极限分析理论,提出一种适用于软弱围岩的深埋隧道围岩压力的计算方法。考虑隧道底部塑性变形区的影响,构建纺锤形的破坏模型。基于该破坏模型构建围岩速度场,引入侧压系数λ_(1)和底压系数λ_(2),推导围岩压力的理论计算公式。根据... 基于极限分析理论,提出一种适用于软弱围岩的深埋隧道围岩压力的计算方法。考虑隧道底部塑性变形区的影响,构建纺锤形的破坏模型。基于该破坏模型构建围岩速度场,引入侧压系数λ_(1)和底压系数λ_(2),推导围岩压力的理论计算公式。根据计算公式进行编程优化计算,分析不同非线性系数m下,侧压系数λ_(1)、底压系数λ_(2)对围岩压力的影响。研究结果表明:随着内摩擦角减小,“纺锤”上下两端塑性区不断向外延伸;非线性系数m对围岩压力有显著影响,当非线性系数一致时,提高侧压系数λ_(1)可以降低拱顶和隧道底部压力,提高底压系数λ_(2)可以降低拱顶和边墙压力;在岩土体非线性特征明显的地区,计算深埋隧洞围岩压力时应考虑底部塑性区。 展开更多
关键词 深埋隧道 极限分析 围岩压力 上限解
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基于多块体上限法的层状珊瑚砂地基承载力分析
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作者 徐东升 刘洋 侯传坦 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第4期921-928,共8页
为研究层状珊瑚砂地基承载能力,基于极限分析上限理论,构建了适用于层状砂土的多块体破坏机构,推导了外力功率与内能耗散率的计算公式.采用序列二次规划优化算法,建立了层状珊瑚砂地基极限承载力的上限分析方法.通过与现有研究成果的对... 为研究层状珊瑚砂地基承载能力,基于极限分析上限理论,构建了适用于层状砂土的多块体破坏机构,推导了外力功率与内能耗散率的计算公式.采用序列二次规划优化算法,建立了层状珊瑚砂地基极限承载力的上限分析方法.通过与现有研究成果的对比分析,验证了所建立方法的有效性,所构建的破坏机构突破了现有分层地基破坏机构下层必须为黏土的局限.结果表明,当破坏机构穿过不同层状地层时,基于层状地基模型与均质地基模型计算得到的地基承载力和临界破坏机构有显著不同,因此有必要考虑不同分层性质.相比于地基载荷试验,所提出的上限分析方法通过调整不同地层土体参数,能够快速得到地基承载力上限值,为珊瑚砂地基设计提供参考. 展开更多
关键词 地基承载力 极限分析 多块体上限解 层状珊瑚砂
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