No.4 CHINESE JOURNAL OF APPLIED MECHANICS The temperature varies with time on fire,and the temperature of the components boundaries varies too.Duhamel theorem.which can na such he co problemsthat the boudary re acco ordance with ain laws,is applied todeduce the formula of th eanalytic in the concrete slab on fire e.The analytical solutions are calculated through MATLAB programming.By comparing the analytical and the test results obtained,it is shown that both of the temperature distributions are nonlinear,and the distributions have the same trend,that is,the surfaces near the fire have great temperature gradient,the farther the slab near the fire,the smaller the temperature gradient is.Both the temperature distribution erature field in the .on the assistant problem is obtained,which same heat conduction but the non-homogeneous items are unrelated to the times,the corresponding heat conduction problem can be solved by using Duhamel theorem.thus this method can be extended to obtain the analytical solutions of the temperature field of other construction members on fire. Study on cooperation mechanism of hybrid masonry structure with RC framing under the action of vertical force Guo Xiuqin Ma Jianxun' Cheng Litao 2 CCCC First Hig Abstraet:Firstly,the computational formula of axial force distribution for the framework and wall on hybrid masonry structure with RC frame is derived under the action of the vertical force.Theoretical analysis to determine the affecting factors of cooperative work on structures under vertical forces and finite element model is established to study the impact of beam height column height.wall height etc.on axial force distribution of frame and wall.Results obtained indicate that imp of column section height on axial force distribution of frame e and wall is and the variation is around%mpact of of frame and wall takes the second place.Impact of beam height and wall height on axial force distribution of frame and wall is not obvious.The accuracy of computational formula is verified by the comparison of results from the model analysis and formula calculation respectively. Keywords:vertical force.axial force distribution.cooperative work Dynamic characteristics of a cylindrical tunnel considering interaction between saturated soil and lining Chen Xueli Wen Minjie (nVcationl Technical Col46nChina) Abstraet:Based n Darey law,the partial permeable conditions on the boundary of tunnel are established by medium with fractional derivative constitutive relations.Based on Biot's theory,the expressions of displacement, stress and pore water pressure for coupled vibrations of saturated viscoelastic soil and elastic lining system subjected to harmonic axisymmetric load or fluid pressure are given in frequency domain by the continuity conditions at the interface between lining and soil Infuences of the order of fractional derivative,materials No.4 CHINESE JOURNAL OF APPLIED MECHANICS vii The temperature varies with time on fire, and the temperature of the components boundaries varies too. Duhamel theorem, which can analyze such heat conduction problems that the boundary temperature varies with time and in accordance with certain laws, is applied to deduce the formula of the analytical solutions of the temperature field in the concrete slab on fire. The analytical solutions are calculated through MATLAB programming. By comparing the analytical and the test results obtained, it is shown that both of the temperature distributions are nonlinear, and the distributions have the same trend, that is, the surfaces near the fire have great temperature gradient, the farther the slab near the fire, the smaller the temperature gradient is. Both the temperature distribution curves are convex toward the coordinate axes. So the formula is suitable for solving the temperature field in the concrete slab on fire. Furthermore, if only the solution of the assistant problem is obtained, which belongs to the same heat conduction but the non-homogeneous items are unrelated to the times, the corresponding heat conduction problem can be solved by using Duhamel theorem, thus this method can be extended to obtain the analytical solutions of the temperature field of other construction members on fire. Keywords: fire, concrete slab, temperature field, analytical solutions, heat conduction, Duhamel theorem. Study on cooperation mechanism of hybrid masonry structure with RC framing under the action of vertical force Guo Xiuqin1 Ma Jianxun1 Cheng Litao2 (1 School of Human Settlements and Civil Engineering, Xi’an Jiaotong University, 710049, Xi’an, China; 2 CCCC First Highway Consultants Co., Ltd, 710049, Xi’an, China) Abstract: Firstly, the computational formula of axial force distribution coefficient for the framework and wall on hybrid masonry structure with RC frame is derived under the action of the vertical force. Theoretical analysis to determine the affecting factors of cooperative work on structures under vertical forces and finite element model is established to study the impact of beam height, column height, wall height etc. on axial force distribution of frame and wall. Results obtained indicate that impact of column section height on axial force distribution of frame and wall is the largest and the variation is around 10%. Impact of masonry elastic modulus on axial force distribution of frame and wall takes the second place. Impact of beam height and wall height on axial force distribution of frame and wall is not obvious. The accuracy of computational formula is verified by the comparison of results from the model analysis and formula calculation respectively. Keywords: vertical force, axial force distribution, cooperative work. Dynamic characteristics of a cylindrical tunnel considering interaction between saturated soil and lining Chen Xueli Wen Minjie (Jiaxing Vocational Technical College, 314036, Jiaxing, China) Abstract: Based on Darcy law, the partial permeable conditions on the boundary of tunnel are established by introducing the relative permeability coefficient of lining and soil. The soil skeleton is treated as a viscoelastic medium with fractional derivative constitutive relations. Based on Biot’s theory, the expressions of displacement, stress and pore water pressure for coupled vibrations of saturated viscoelastic soil and elastic lining system subjected to harmonic axisymmetric load or fluid pressure are given in frequency domain by the continuity conditions at the interface between lining and soil. Influences of the order of fractional derivative, materials