The main purpose of this work is to simulate turbulent premixed and expanding flame in an adiabatic combustion chamber without taking into account flame-walls interactions. The turbulence is supposed to be isotropic and homogeneous with no decay or decreasing, but spatially correlated. The chemistry is represented by a four-step scheme of methane-air combustion. A one-dimensional simulation is considered because of the spherically symmetric of the problem. Ignition occurs in the middle of the domain thanks to an energy source such a spark. The simulation, based on Monte Carlo scalar probability density functions (PDF) transport method, is used under different equivalence ratios (ER) and different turbulence intensities (u'). We have placed our emphasis on some flame characteristics such as the flame mean radius, the turbulent flame radius, the flame propagation velocity, and the flame brush thickness. The results of our simulations, carried out in similar conditions to some available experiments, are in good agreements. Indeed, we notice that the flame radius is enhanced by ER at constant u', and by u' at constant ER. The flame brush thickness shows a quick growth at the first stage and a moderate growth in the intermediate regime, but a bending effect is observed in the final stage of the so-called "fully developed flame".