| The cement concrete pavement, as one of the high-grade pavement structures, has been widely used because of such advantages as high strength, good stability, great durability, high temperature stability, abrasive hardness and low cost of maintenance. In line with the theories of the present pavement designs, the cement concrete pavement, with normal performance in the structure of every layer, ideal interlayer contact as well as good designs and construction, will usually not break until a long time of use or the time designed. But actually, quite a number of such pavements show defects or crackles of varying degrees within 2-5 years or shorter. Meanwhile, owing to its features such as high cost for maintenance, severe traffic interference during maintenance, and difficulty in maintenance of what is damaged, it is a problem deserving immediate solution in present-day projects to know the fissure mechanism and breaking process of the cement concrete and improve its anti-fissure performance.Therefore, the present paper, based on the existing achievements as well as an extensive study & investigation in combination with part of the achievements the author has derived by hosting or participating in the research programs of the cement concrete pavement, has led to three phases of fissures and breaking in the pavement slab on the condition that each performance of the subgrade is maintained, i.e. stages of formation in initial cracks, of accumulation & expansion in ruptures and of fissures & breakage in the pavement. Meanwhile, the factors causing fissures in the pavement fall into three layers from down to up,namely, the bottom layer of the pavement slab-the formation and fissures &breakage of the transition layer between the pavement and base interface makes the chief reason for the formation of initial cracks and later fissures; the middle layer-the pavement plate. The pavement panel, under load and with already existing initial cracking & inherent damaged conditions as well as its cracks & damage, further accumulates and expanses, which lays a foundation for the fissures & breakage; the surface layer- as the uneven pavement brings aboutinteraction between spring plates which results in impact on the vehicle load, is the main reason speeding up the fissures in the pavement panel. And through the evidence of tests, the paper brings forward some technically relevant measures to reduce fissures and breakage in the pavement panel. Finally, in view of the complexity and non-linearity of the pavement in cracking and breakage, the paper tries to explain the formation in the cracks of the pavement and mechanism & process of expansion by nonlinear theories (like chaos , fractal etc.) and to describe the whole process of fissures and breakage so as to provide a new thought and method for the study of the cement concrete.. What is shown in the paper is of great theoretical and practical significance to the perfection of theories in pavement designs and construction methods, to the eradication or reduction of hidden risks in the pavement as evidence for the research of new anti-fissure materials in the pavement, new technology and new techniques. The paper has a few creative points to recommend as follows:1. Through the research and analysis on the three aspects concerning the base interface of the pavement panel, crack accumulation, expansion in the pavement panel and interaction between spring plates on the road surface as well as its damage on the road fatigue, it is first brought forth that the process of fissures and breakage in the cement concrete pavement can be divided into three stages, i.e. stage of initial crack formation and damage in the bottom of the pavement slab, stage of accumulation, intensifying & expansion in ruptures from load during the time of use and stage of fissures & breakage in the pavement.2. Aiming at the binding relationship between the pavement and the base, the author, by collaborating with related research groups, bring forth for the first time the formation of a weak tran...
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