为研究斜向施加预应力路面的受力特性，通过理论推导由斜向预应力产生的路面板内压应力计算公式，预应力筋的直径、布设角度和间距是影响板内应力的主要因素。建立力学模型，模拟分析预应力筋作用位置、布设间距和角度以及直径大小对路面板应力的影响，结果表明，斜向预应力混凝土路面的锚固区和板角部分区域出现拉应力，但混凝土不会出现开裂；预应力筋布置在1/2板厚偏下是合理的，此时板底压应力大于板顶部，路面板产生负弯矩；预应力布设角度建议范围为25°～45°；考虑到经济性和预应力筋张拉空间，建议预应力筋布设间距最小为0．5 m，预应力筋的布设间距也不能过大，过大易造成路面板应力分布不均匀；可通过调整预应力筋的直径，以得到合理的布设角度和间距。%In order to study mechanical characteristics of the cross-tensioned prestressed concrete pavement,calculation formulas for the average compressive stress caused by prestressing was deduced, diameter,the angle and distance of tendon are the main factors.the finite model of cross-tensioned pres-tressed concrete pavement was built,the effect of tendon location,the angle of tendon applied and dis-tance between tendon and diameter on stress distribution were also analyzed.The test results show that, because of cross-tensioning,the tensile stress will appear at anchorage zone and corner of the slab,but concrete cracking will not occurr;it is reasonable to place the tendon bellow the mid-depth of the slab,at this depth,the compressive stress of the bottom slab is larger than the top of that,lowering tendon bellow the mid-depth of the slab causes the slab to have an induced negative moment;the recommended angle, at which the tendon applied,should be 25 °~45 °;the minimum distance between the tendon should be 0.5 m considering economy and the tensioning space rope,the distance between the tendon should not be too large,otherwise the uneven stress distribution of the slab could be caused;in the event that the cal-culated distance between tendon is too close or the calculated angle is too large,diameter of tendon should be adjusted to increase compressive stress of the slab and the reasonable distance and angle will be obtained.
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