福建省跨世纪干线公路网规划构思

为适应福建省跨世纪经济发展的需要，本文介绍了正在制定的我省干线公路网规划，并就规划的原则、目标以及综合评价进行论述，提出本世纪内由“制约型”向“基本适应型”，继而在２１世纪前２０年达到“超前型”的战略目标

An Experimental Analysis of the Cement Concrete Mixed with Powdered-Coal Ash

In this paper, the forming mechanism of the strength and the physical and mechanical performance change of the road cement concrete after being mixed with powdered-coal ash is preliminarily explored and analysed. The experimental analysis shows that, it is possible to mix a few powdered-coal ash into the road cement concrete instead of cement. It can keep its original strength. This is because when it is excited by the active CaO which is produced by the hydration and hydrolysis of the cement, the ingredient of SiO 2in the powdered-coal ash can form the moisture crysral together with SiO 2. It takes the place of the function of the reduced cement. However, the strength of cement concrete will diminish when the mixture quantity of the powdered-coal ash goes beyond certain limit. The reasonable quantity of mixture is 15%(internal mixture).