涵洞顶填土压力的计算分析

简要介绍了圆管涵破裂的原因，论述了根据公路规范、铁路规范计算涵洞顶场土压力的方法及其缺陷，提出了种新的涵洞顶场土压力计算方法。计算结果表明，该方法克服了上述两种规范中计算方法的不足。     

Australia's Box–Ironbark Forests and Woodlands: saving the fragments of a threatened ecosystem

Australia's box–ironbark forests and woodlands once covered about 14 per cent of the State of Victoria on the riverine plains and foothills of the Great Dividing Range. But approximately 83 per cent of the total original habitat has been destroyed and what remains of this significant ecosystem is now highly fragmented and vulnerable to further degradation. Moreover, only 14 per cent of the area remaining is on public land. A 10 year campaign on the part of the environmental movement eventually succeeded in forcing the State government to conduct an independent inquiry into this ecosystem and make recommendations on future management. This paper outlines the innovative public participation process adopted by the Victorian State government and the outcomes of the inquiry. A subsequent compensation package for commercial operations disadvantaged by the proclamation of a series of new national parks is also discussed, as are the shortcomings of a process that can have little or no impact on what happens on private land.     

基于探空资料的西南区域暴雨环境参数统计分析

利用西南区域11个探空站数据及地面常规观测资料,对2010～2020年196次暴雨过程中表征水汽、热力不稳定、动力条件的10种物理量参数进行统计分析,基于箱线图提取了一些有利于暴雨发生的环境参数阈值。结果表明：（1）对流层中低层近饱和的大气和比湿高值是该区域暴雨发生的有利条件之一;（2）沙氏指数在各季节的阈值均较低,对流有效位能在盛夏时值较高,多对流性暴雨,而初秋对其要求不高,多稳定性暴雨;（3）初夏和盛夏对最大上升速度的要求明显大于初秋,而能量螺旋度主要在初夏才有一定要求。