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声波透射法在混凝土灌注桩完整性检测中的应用 总被引:1,自引:0,他引:1
用实例介绍声波透射法在混凝土灌注桩(模型桩)桩身完整性检测中的应用效果,确定缺陷的范围。试验证明,该方法能有效检测混凝土缺陷及其位置。 相似文献
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受强降雨影响,湘东南地区近年来残坡积层滑坡大量发生.滑坡类型多属小型一浅层一牵引式;滑坡形态具有:周界不规则、表面台阶状、前缘土体崩溃状、滑动面叠瓦状及多层性,滑坡发生具有:突发性、群发性与继发性、随机性;滑坡的主控因素:斜坡结构、坡脚临空面、降雨;防治建议:完善地质灾害信息系统、建立降雨-滑坡研究预报体系、加强边坡管理、以防为主综合治理. 相似文献
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Based on the definition of Binary Tropical Cyclones (BTCs), the definition of influencing china binary tropical cyclones (ICBTCs) was proposed. During the BTCs period, if at least one of the two tropical cyclones causes precipitation over the mainland or one of the two largest islands-Hainan and Taiwan of China, the BTC is called ICBTC. Then, based on daily precipitation data and the tropical cyclone best track data during 1960-2017, this study analyzed the climatic characteristics of ICBTCs using the Objective Synoptic Analysis Technique (OSAT) and the above definitions. First, a total of 255 pairs of ICBTCs, which accounted for 60.6% of the total number of BTCs over the Western North Pacific, occurred with an annual average of 4.4. Annual frequency of ICBTCs showed a significant decreasing trend during 1960-2017. The longest duration of ICBTCs was 10 days, while durations concentrated in 1 day, 2 days and 3 days, accounting for 18.8%, 29.4% and 24.3%, respectively. In terms of geographical distribution, the ICBTCs mainly occurred over the range of 112°~138°E, 12°~30°N, with frequent zones in the oceans around the northern Philippines. In addition, both annual mean frequency and precipitation of the ICBTCs decrease from the southeast coast areas to the northwest inland regions, with severely-affected areas being the Taiwan Island, the Southeast Coast and the South Coast, and the most-severely-affected area being the Taiwan Island. Further analyses reveal that the average position of the two TCs on the maximum daily precipitation day during the ICBTCs period show an east-west distribution pattern, with the western TCs and the eastern TCs locating in the southwest wind water vapor channel of the East Asian Summer Monsoon and the warm-wet air flow of the southeast-wind on the southwest side of the subtropical high. This situation is beneficial to the western TCs obtaining water vapor from the southwest wind water vapor channel, and to the eastern TCs conveying water vapor to the western TCs, and then as a result, to the heavy rainfall over the Taiwan Island, the Southeast and the South Coasts of China caused by the western TCs. 相似文献
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针对嵌岩桩桩端硬持力层厚度小于3d的实际情况,为确保安全又节省造价,在分析桩一岩土体系的荷载传递机理和岩石破坏模式的基础上,建立桩端硬持力层的冲切承载力计算公式,用该公式计算桩端硬持力层厚度的冲切承载力,并与桩基设计荷载相除得到安全系数K,根据安全系数K的大小判定桩端硬持力层的厚度能否满足荷载要求。工程实例表明,该方法在红层地区的运用效果好,可供借鉴。 相似文献
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近58年南岳高山气温变化特征及与低海拔地区对比 总被引:1,自引:0,他引:1
运用线性回归对南岳高山气象站自建站以来(1953-2010年)的年、季平均气温、最高(低)气温进行气候趋势分析,同时用非参数Mann-Kendall检验(MK检验)和滑动T检验确定其突变位置.通过上述方法,获得半个多世纪以来在近对流层自由大气底部这一特定高度上,南岳高山气温变化规律.通过与衡山县、衡阳市近50年气温变化对比,分析南岳高山与低海拔地区气温变化的差异性及城市化对其影响程度,结果表明:近58年来,在周边环境变化很少且受人类活动影响不大的前提下,南岳高山年平均气温、最高(低)气温呈显著上升趋势,分别上升了1.0℃、0.8℃和1.1℃;四季平均气温和最低气温均呈上升趋势,而最高气温除了在夏季出现呈微弱下降趋势外,其余季节呈上升趋势;年平均和最低气温在1996年发生了突变,而最高气温突变点不明显;城市化发展对当地气温上升有一定的加强作用,但观测环境改变,对夏季气温变化影响更为明显. 相似文献
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在综合勘查及水文测试资料的基础上,根据用口地热田的地热地质特征,分析地热田地热流体的特征和成因。结果表明用口地热田属低温地热资源,资源丰富,水质良好,是受断裂控制的带状热储型地热田。 相似文献