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排序方式： 共有253条查询结果，搜索用时 15 毫秒
91.
人造砂岩具有参数可控特点,可广泛的应用于物理模拟及实验研究领域,文章介绍了压制法制作人造砂岩的基本流程.对人造砂岩物理参数及声学性质进行实验研究.测量了密度、孔隙度等参数,给出压制压力与密度、纵波速度关系图.利用超声波透射法测量人造砂岩纵横波速度,对人工砂岩在饱含气与饱含水状态下速度变化进行定量分析,给出纵横波速度随孔隙度变化曲线.饱含气状态变化到饱含水状态后,纵波速度上升,横波速度下降.利用Gassmann方程对流体替换后速度进行预测,实际测试数据的纵波速度与预测计算数据比较吻合.纵横波速度变化规律与天然砂岩基本一致. 相似文献
92.
The mechanical property of saline soils varies with moisture and climate in the cold and salt lake region of Qinghai-Tibet Plateau, which influences
project construction. In order to improve foundation reinforcement effect of the Qarhan–Golmud Highway, Qinghai Province,
China, dynamic compaction replacement (DCR) composite foundation was applied in saline soils. A field experiment was conducted in this
area, where strength and working mechanism of pier-soil and deformation modulus of the composite foundation was analyzed after reinforcement.
This paper presents methods for determining the coefficient on the bearing capacity evaluation and deformation modulus of
composite foundation with DCR. Reinforcement case of DCR is highly effective in saline soils of the salt lake regions, which helps the migration
of water and salt in saline soils. 相似文献
93.
我国进入经济发展的快速时期,各个地方尤其是城市化和工业化发展较快的地区对建设用地的需求越来越大,开展对土地的整治和置换已经上升为国家层面的战略部署。本文在对安徽省建设用地管理现状和存在问题进行分析的基础上,提出未来安徽省土地置换政策制定的工作思路与目标任务。 相似文献
94.
???????????????·???????·?亭???????????????????????????????????????????????????????????????????о??п?????????????????????????????????????????????????????????С? 相似文献
95.
Residence times of the three main channel systems of Manukau Harbour were calculated by methods based on the salinity measured in 10 tidal excursion segments: the freshwater replacement technique and a volume exchange model. The amount of freshwater present in the segments at high water was low (< 11% throughout the year), so salinities were high, with minimum values (winter) in each segment being in the range 30.1–34.0 (compared with a median value of 34.5 in the nearby coastal waters). The proportion of each segments’ volume which was exchanged with an adjacent segment during a tidal cycle varied markedly across the harbour, from ≤ 5 % in several shallow inner harbour segments to 65% in a deep segment adjacent to the entrance channel. For annual average conditions the freshwater replacement times of the channels were 11–18 days. Slightly longer residence times—12–26 days—were obtained from the volume exchange model. Calculated replacement times for two non‐conservative tracers— inorganic phosphorus and nitrogen—were approximately half those for freshwater, as 5–12% of these species disappeared from the water column each day. 相似文献
96.
In order to accurately design a sand compaction pile (SCP) with low replacement area ratio, it is important to understand the mechanical interaction between the sand pile and clay ground and its mechanism during consolidation process in composite ground. In this article, therefore, a series of numerical analyses on composite ground improved by SCP with low replacement area ratio were carried out. The applicability of numerical analyses, in which an elasto-viscoplastic consolidation finite element method was applied, were confirmed by comparing the results obtained from a series of laboratory model tests with the composite ground improved by SCP. Through the results of the numerical analyses, mechanical behavior of the sand pile and clay in composite ground during consolidation is elucidated, together with a stress sharing mechanism between sand pile and clay. 相似文献
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99.
从广西北部湾大量填海（塘）造陆工业基地所遇到的复杂型软弱与夹层地基处理工程实例中,结合建（构）筑物具体特点,扩展应用置换（挤密加固,纵横排水）碎石桩联合强夯的地基处理方法,在解决大面积地基不均匀沉降,软弱夹层纵横排水与挤密固结、综合夯实提高总体地基持力层承载力方面取得了“安全、经济、高效”的良好效果,并具有推广前景和意义。 相似文献
100.