Research on method of pressure grouting piling of driven tube

The pressure grouting pile of driven tube can improve the load bearing capacity of the single pile from the mechanism of pressure grouting pile of driven tube.On the basis of analyzing the mechanism,the authors designed the machines and tools of pressure grouting,determined the operating manufacture and technology parameter on the pressure grouting secondly.The result shows that the pressure grouting pile of driven tube not only changes the pile type but also reduce the length of the pile and its engineering cost,it enhances the load bearing capacity of single pile an the same time.     

方斑东风螺两种养殖模式的比较

在室内水泥池，利用沙层自净养殖模式和直接铺沙养殖模式对不同规格的方斑东风螺（Babylonia areolata Link）进行了高密度养殖的研究。结果表明，沙层自净养殖模式养殖小螺、中螺、大螺组日均增重分别为0．031、0．088、0．098g／d，沙层NH4^＋-N最高含量ω分别为1．3、2．1、3．1mg,／L,H2S最高含量ω分别为0．03、0．07、0．14mg／L．各规格组东风螺保持正常生长和活动，成活率92．9％以上；直接铺沙养殖模式养殖小螺、中螺、大螺日均增重分别为：0．023、0．051、0．068g／d．成活率分别为95．2％、86．7％、84．9％，沙层NH4^＋-N最高含量ω达到13．7mg／L，H2S最高含量ω达到0．47mg／L，沙层底质恶化，东风螺活动异常、不摄食。可见，沙层自净养殖模式对方斑东风螺的生长、成活率、沙层水质控制效果显著，在一定程度上克服了直接铺沙养殖底质恶化问题。     

手持式激光测距仪前级接收通道的相关问题研究

介绍了手持式激光测距仪前置放大电路的设计方法,并且针对便携式设备供电的特殊性,给出了单电源供电放大电路的解决方案,较好地解决了前级接收通道电路设计的相关问题.     

花岗岩残积土桩基施工中的问题及解决办法

文章总结了梧州市常用的沉管灌注桩、钻孔灌注桩和人工挖孔桩在以花岗岩残积土为桩基持力层时施工中的特点及容易出现的问题 ,并提出相应的解决办法     

用高温石墨管原子吸收分光光度法测定土壤和污泥中的镉、铅、铜、镍、钴

Some soft and mud samples have been determined for eadmiun, lead, copper,nickel and cobalt by atomic absorption speetrophotometry with a high-temperature graphite tube, after their extraction with sodium diethylthiocarbonate into methy lisolutyl ketone. The tests of the effects of acidity on extraction and interference have been also carried out and the optimum conditions have been obtained. In addition, experiments on recoveries by this procedure have been performed for the elements in ppb amount. The recovery of the metals added to soil samples is made in the same manner and the precision values are given in this paper. This method is considered as to be applicable to the determination of soil and mud samples for the above-mentioned elements, of which the concentration is higher than 1 ppb.     

Centrifuge modeling of PGD response of buried pipe

A new centrifuge based method for determining the response of continuous buried pipe to PGD is presented. The physical characteristics of the RPI‘s 100 g-ton geotechnical centrifuge and the current lifeline experiment split-box are described: The split-box contains the model pipeline and surrounding soil and is manufactured such that half can be offset, in flight, simulating PGD. In addition, governing similitude relations which allow one to determine the physical characteristics, (diameter, wall thickness and material modulus of elasticity) of the model pipeline are presented. Finally, recorded strains induced in two buried pipes with prototype diameters of 0.63 m and 0.95 m (24 and 36 inch) subject to 0.6 and 2.0 meters (2 and 6 feet) of full scale fault offsets and presented and compared to corresponding FE results.     

牢记先生教导到设计中去到施工中去

谷德振先生"重视实践"的学术思想是他"重视实践"、"地质力学"、"岩体力学"、"岩体稳定性研究"学术思想中"最重要的,最突出的、放在首位的学术思想"[1].这一思想归结起来就是重视工程前期的工程地质考察和勘查工作;到设计当中去;到施工当中去.本文首先阐述了谷先生"重视实践"的学术思想的形成过程和具体体现;然后,以我国解放后第一座跨越1200m江面的八墩九孔钢结构双用桥岩基勘查和基础工程设计和施工为工程范例具体、生动地体现他"重视实践"的学术思想;最后,指出长江三峡工程是谷先生生前最为关注并浇灌辛勤汗水的水电工程,谷先生"重视实践"的学术思想已在长江三峡库区二期地质灾害治理工程和即将在三期地质灾害治理工程的地质勘查、设计和施工中发挥重要的指导作用.     

不同布缆方式锚碇沉管管段运动的数值模拟

通过建立波浪作用下锚碇沉管管段运动的时域数值计算模型,对锚碇沉管的运动响应及锚碇缆受力特性进行了研究。应用集中质量法求解锚碇缆力,应用四阶Runge-Kutta法求解管段时域运动方程,计算了在不同沉深、不同周期、不同波高和不同波向条件下沉管管段的运动幅值和锚碇缆力。数值计算的结果表明:锚碇沉管的锚碇缆对沉管管段的运动起到一定的约束作用,在沉放深度较浅、波浪周期较大时,锚碇缆对沉管管段运动幅度的制约更为明显。通过五种布缆方式的计算与分析,探讨了布缆方式对沉管管段运动响应及锚碇缆受力的影响,并给出了较为合理的布缆方案。