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通过对二部规范的对比,阐明“地基基础”与“桩基”相比在桩基础设计中作了较大的调整,这样既节省了工程造价又提高了桩基础设计质量。 相似文献
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本文根据胶合板厂实际情况,建立了杨木胶合板厂生产规划模型。该模型考虑各主要设备工段、产品组合、产品混合、产品价格、流动资金、原材料供应以及市场约束等问题。本模型能够满足市场竞争,获取最佳利润,同时还能解决胶合板厂“三板”(表、背、芯单板)不平衡问题。 相似文献
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The existence of ettringite in sulphoaluminate cement hardened paste is mainly in the form of pole-like crystal,which causes unfavorable effect on the cement.In this paper the strength and microstructure of the sulphoaluminate cement containing ultra-fine CaCO_3 weze discussed.Experimet results show that the strength of sulphoaluminate cement was obviously improved by adding 3% of ultra-fine CaCO_3.After curing for 28d,the compressive strength of cement paste and mortar is 100.6MPa and 94.1MPa respectively,and the bending strength of the mortar reached 12.5MPa.SEM study on hardened paste of sulphoaluminate cement containing ultra-fine CaCO_3 showed that its structure was dense and homogeneous,there was hardly any massive crystall detected. 相似文献
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《保鲜与加工》1997,(6):58-62
In this paper,in terms of the measured data(including the deflection and slope at the ground surface of the pile,the maximum bending moment and its position),the biparameter method is used to analyze the pile-soil parameters.Two examples show that the method in present paper is reasonable and reliable,and it provides the reference value for the engineering design. 相似文献
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Some conclusions were drawn from two groups of in-site tests on concrete pile composite foundations. In the tests, it was found that the pressure under the rigid loading slab is different, in which the pressure under the center of the slab is the less and under the edge of the slab is the biggest. The pile-soil stress ratio is not a constant; it increases with the adding of the load. Most of the pile-soil ratio vary from 9 to 13 in these tests and the load that the piles share can be more than seventy percent of the whole load. It was proved that the bearing capacity of the concrete pile composite foundation is high with a little settlement, so it will be used more and more in the future. 相似文献
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In this paper the working principle and performance character of both the manual and automatic Vicat apparatuses in existence are compared and analyzed,and their existing weakness and the urgent problem to be solved are pointed out.On this basis,adopting the technology of mechatronics and modern sensors,a new sort of full automatic Vicat apparatus that can fully satisfy the national standard in testing the setting time of the cement has been developed.This apparatus can be operated expediently with high precision,the test results are to be analyzed and computed automatically.This paper presents the working principle,performance character,key technology and prospect of application for the full automatic Vicat apparatus. 相似文献