南沙港区陆域吹填工程真空预压软基处理技术

介绍在南沙港区真空预压加固施工中,采用土工织物对吹填淤泥进行表面处理、水平排水板处理含泥量高的砂垫层及长短搅拌墙相结合的密封技术     

预压托换法加固补强钢筋混凝土灌注桩基础

分析了预压托换桩加固桩基的力学机理 ,详细介绍预压托换设计、施工及静载荷试验。表明预压托换桩法加固补强灌注桩基础是可行的     

塑料排水板真空预压法在顺德市德胜大道路基处理中的应用

顺德市德胜大道路基原为深厚淤泥层，选用塑料板真空预压法，塑料板插入距淤泥层下承压水１５～３ｍ，砂垫层上密封薄膜埋入沟槽全面复水，并用２～３道帷幕灌浆隔离周围水体。此法效果良好达到设计要求。     

The phenomenon of anisotropy of the resistance to microcleavage for a carbon steel prestrained in compression

The effect of compressive plastic prestrain on the resistance of carbon steels to microcleavage is investigated using grade 30 steel as an example. Precompression is found to result in the occurrence of anisotropy of the “brittle” strength R_mc of the steel, the essence of which is in its decrease for specimens cut out in the longitudinal direction and increase in the microcleavage resistance for specimens cut out in the transverse one. It is shown that the main cause of this effect are oriented residual stresses. The value of the oriented residual stresses for specimens cut out in the longitudinal and transverse direction is estimated. A strong embrittlement of the steel is observed in the longitudinal direction after compression. The shift in the ductile-brittle transition temperature reaches the maximum value of 168°C. __________ Translated from Problemy Prochnosti, No. 6, pp. 91–102, November–December, 2007.     

天津市水利工程地基处理方法分析

对天津市软土地基的物理力学性质进行了分析,详细地介绍了多种软弱土地基的处理方法,强调了软基处理中应注意的问题,为各种处理方法在水利工程地基处理中的应用奠定了基础。     

纸蜂窝材料的有效缓冲及其预压缩试验

通过对纸蜂窝材料(蜂窝纸板)进行预压缩试验的方法,研究了预压前后纸蜂窝材料缓冲性能的变化,提出了纸蜂窝材料有效缓冲的概念。进一步研究了不同预压缩率下纸蜂窝材料缓冲性能的变化,得到了一组缓冲系数C-最大静应力σm曲线,此曲线可以方便缓冲包装设计的材料选择。     

浅谈现浇连续梁满堂支架施工

结合某客运专线现场实际现浇连续梁施工,对连续梁满堂支架的几道关键施工工序：地基处理、支架搭设、支架预压、支架验算进行了详细的介绍,对积累的相关施工经验进行了简要总结,以便共同促进提高满堂支架施工技术,更好的指导现场施工。     

填海区软基处理工程的施工技术和管理

塑料排水板加载预压法对软弱地基进行处理，是近年来对填海区地基采用的基本方法之一。本文以深圳湾填海区为例，详细介绍了具体的施工技术及管理措施。     

Effect of Compressive Deformation on Wear Property of Extruded ZK60 Magnesium Alloy

The present study investigates the dry sliding wear behavior of precompressed ZK60 alloy using a ball-on-disc wear test machine under normal loads of 20 and 40N at a sliding speed of 0.5m s^?1 for a constant sliding distance of 1,500m. Microstructures and worn surfaces were characterized by optical microscopy and scanning electron microscopy. Microhardness measurements were taken to evaluate mechanical properties. Results showed that both the microhardness and wear resistance of uncompressived alloy can be improved with precompression. This is attributed to the grain refinement via subdivision of twin lamellae generated by compressive deformation. Furthermore, the worn surface studies showed a mixed type of wear mechanisms: oxidative and delamination wear took place under higher applied loads.     

预压缩处理对镍基单晶高温合金蠕变变形机制的影响

对[001]取向镍基单晶合金进行预压缩处理,获得P-型筏状结构后进行拉伸蠕变实验,测定P-型γ'合金(预压缩态)与立方γ'合金(热处理态)的相对蠕变性能.结果表明:在800 ℃,600 MPa条件下,P-型γ'合金的初期蠕变应变及稳态蠕变速率相对较高,而持久寿命相对较短.TEM观察显示,P-型γ'合金在蠕变初始阶段除了基体中的{111}<110>多滑移启动外,位错还以层错和超位错的形式切入γ'相.在980-1020℃温度区间及恒定载荷200 MPa条件下,P-型γ'合金的稳态蠕变速率相对较低,持久寿命相对较高.在稳态蠕变初期,合金中的γ'相有效地抑制了位错沿垂直γ/γ'界面的攀移运动;而在稳态蠕变中期,γ'相被稠密的位错网包围,位错难以切入,合金的蠕变抗力提高.