## 1 Introduction  
The stiffened composite laminated plate is widely used in steam boilers with longitudinal tubes, bodies' ships and submarines' space crafts by taking into consideration the high stiffness and the ratio between the high strength and low weight. The nonlinear dynamic phenomenon in a stiffened plate due to the bending deflection through the plate thickness could be either a periodic motion or non-periodic motion and chaos. [PERSON] and [PERSON] studied the non-linear dynamic buckling behavior of laminated composite curved panels when the plate is subjected to a rectangular pulse load at various amplitude and durations. They used finite element analysis to study the effects of aspect ratio, the radius of curvature and the thickness ratio on the nonlinear dynamics phenomenon of composite plate [1]. [PERSON] and [PERSON] used B-spline function in finite element analysis to analyze the unidirectional in-plane compression pulse loading [2]. They studied the effect of nonlinear dynamic pulse buckling such as sinusoidal, exponential and rectangular on the shock spectrum using the Tsai-Wu quadratic interaction criterion. A nonlinear finite element method is presented by [PERSON] et al. to investigate the nonlinear stability of stiffened functionally graded materials (FGM) plates [3]. They studied the influence of material properties, geometrical properties of stiffeners and initial deflections on the buckling and post-buckling responses of the stiffened plates. [PERSON] et al. applied [PERSON]'s principle to present the solution of the dynamic buckling of stiffened plates under in-plane impact loading [4]. They used the Galerkin method with the aid of Fourier series to determine the deflection of the plate. [PERSON] studied the nonlinear dynamics behavior of the bending deflection for the composite laminated plate using the conception of the largest Lyapunov exponent. A power spectrum analysis has been conducted using the amplitude of Fast Fourier Transform (FFT) to detect the non-periodic motion of the bending deflection [5; 6]. [PERSON] presented the dynamic analysis of a stiffened and unstiffened composite-laminated plate using a high-order finite element [7]. The shear effect had been taken into consideration in the derivation of the deflection to avoid the problem of un-symmetry in the stiffness matrix. [PERSON] and [PERSON] solved the nonlinear dynamics equation numerically for different loading amplitudes and various loading durations to obtain the buckling response [8]. [PERSON] and [PERSON] performed the stability of infinitely wide composite plates under the effect of suddenly applied thermal and mechanical loading. They showed an efficient tool of the dynamic buckling in composite plates under various type of loading [9]. [PERSON] et al. studied the nonlinear vibration of composite laminated plate against time by solving the dynamic equation of motion using von Karman nonlinear plate theory. They analyzed the amplitude-frequency curve of the displacement against time at different ply angles of the composite laminated plate [10]. [PERSON] applied dynamic tools such as phase portraits, Poincare maps, a fast Fourier transform (FFT) analysis and largest Lyapunov exponents on the isotropic plate. He used the vibration theory of the dynamic to describe the theory of bifurcation and chaos in terms of its dynamic stability and instability regions [11]. [PERSON] studied the nonlinear dynamic behavior of post-buckled composite plates experimentally and theoretically. Experimentally he applied harmonic loads by using an electro-dynamic shaker to measure the dynamic response of the plate specimens based on the single-point displacement-sensing laser approach. The chaotic and periodic motions behavior of the plate response were investigated using classical laminate plate theory and a finite element model [12]. In this paper, the composite plate is subjected to an in-plane compression mechanical load and shear force.