变单向压力下重塑膨胀土膨胀试验研究

为了研究胀限与变单向压力和初始含水率、三向膨胀率与变单向压力和初始含水率的关系，用“膨胀土三向胀缩测试仪”对广西宁明灰白重塑膨胀土进行了三向等压（27 kPa）的情况下变单向压力（27~164 kPa）的膨胀增湿试验。对试验数据进行拟合、对比分析得出：胀限可与变单向压力的对数进行线性拟合，胀限由三向压力决定，与初始含水率无关；无论水平向压力还是竖直向压力，均会抑制该向的膨胀变形，该向膨胀可与该向压力的对数进行一次线性拟合；三向中任一向加压都会同时促进另外两向膨胀变形，该向压力越大，对另外两向膨胀变形的促进作用越大；相同压力条件下，三向膨胀率均与初始含水率呈一次线性负相关；当竖直向压力为水平向压力的2倍时，各向膨胀率与初始含水率关系曲线基本重合。

单向压力封闭剂的作用研究

本文讨论了单向压力封闭剂对钻井液常规性能的影响。试验结果表明,单向压力封闭剂在正向压力作用下对过滤介质孔隙有暂堵作用;在负向反排压力作用下又易于从岩芯中排放出来。证实了单向压力封闭剂具有封闭渗透性岩层裂缝和保护油气层的优良性能。

单向压力暂堵剂在保护油层中的应用

新疆克拉玛依油田东北部的446井区,地层孔隙压力呈上高下低,中部的三工河及八道湾地层裂缝发育,夹有煤层,并有异常压力（西部的扩边井压力系数高达1.42）,由于泥岩的水化膨胀,煤层的剥落掉块及孔隙压力系数的异常,井塌、井漏及井涌现象频繁;白碱滩组储层的压力系数偏低,只有0.98～1.03,胶结物以泥质胶结为主,渗透率为20×10-3～30×10-3μm2,平均孔隙度为16%,孔喉直径为0.30～4.70μm,属低孔隙、低渗透油层,储层含粘土总量高。

单向压力封堵剂在446井区保护油层中的应用

为了解决446井区地层压力系数上高下低,裂缝发育、井塌、井漏不时发生,油层损害严重的问题,研究采用单向压力封堵剂,在钻井液中有利于形成滤饼屏蔽层,护壁性和防塌、防漏效果好,保护油层效果明显,使得机械钻速、原油产量等各项指标有较大幅度提高,技术经济效益较好。

LBM低固相钻井液在煤柳7井的应用

介绍了ＬＢＭ低固相钻井液体系的性能特点及其在煤柳７井的应用，提出了ＬＢＭ体系的工艺要点，评价了ＬＢＭ体系的技术经济性。

心脏手术代用静电泵与阀的结构参数设计

设计了一套由静电泵及压力机械阀组成的人工心脏系统,探讨了以体外静电泵及单向最低压力机械阀替代心脏的二尖瓣和三尖瓣、主动脉瓣和肺动脉瓣,完成体外循环心脏手术的可行性,介绍了静电泵及压力阀的工作原理,提供了泵阀系统与体内动静脉的连接方案,完成了在极值血压状态下的泵阀相关参数的计算,该系统具有与心脏相应器官的血压变化的数值一致性的特点,将会有好的应用前景。

Sensor monitoring of a newly designed foundation pit supporting structure

A new type of pit supporting structure, which was tested and verified using the sensor monitoring technology, was presented. The new supporting structure is assembled by prefabricated steel structural units. The adjacent steel structural units are jointed with fasteners, and each steel structural unit has a certain radian and is welded by two steel tubes and one piece of steel disc. In order to test and verify the reliability of the new supporting structure, the field tests are designed. The main monitoring programs include the hoop stress of supporting structure, lateral earth pressure, and soil deformation. The monitoring data of the field tests show that the new supporting structure is convenient, reliable and safe.

Pressure-impulse diagram with multiple failure modes of one-way reinforced concrete slab under blast loading using SDOF method

Two loosely coupled single degree of freedom (SDOF) systems were used to model the flexural and direct shear responses of one-way reinforced concrete slabs subjected to explosive loading. Blast test results show that the SDOF systems are accurate in predicting the failure mode of the slab under blast loads by incorporating the effects of the strain rate effect caused by rapid load application. Based on different damage criteria, pressure-impulse (P-I) diagrams of the two failure modes were analyzed with the SDOF systems. The effects of span length, concrete strength, and reinforcement ratio of the slab on the P-I diagram were also investigated. Results indicate that a slab tends to fail in direct shear mode when it is of a smaller span length and tends to fail in flexure mode when it is of a larger span length. With the increase of the concrete strength or reinforced ratio, both the flexure and shear capacity increase. Based on numerical results, a simplified method and a semi analytical equation for deriving the P-I diagram are proposed for different failure modes and damage levels.

Embedded Software Control of a Hybrid Vehicle＇s ECU/FCM System

This paper describes a research project that uses embedded systems design principles to construct and simulate an Engine Control Unit （ECU） for a hybrid car. The ECU is designed to select a fuel type based on the stress level of the simulated engine. The primary goal of the project was to use a robotics kit, connected to sensors, to simulate a hybrid car under certain stress conditions such as hill climbing or full throttle. The project uses the LEGO~ Mindstorms~ NXT robotics kit combined with a Java-based firmware, a pressure sensor to simulate a gas pedal, and a tilt sensor to determine when the car is traveling uphill or downhill. The objective was to develop, through simulation, a framework for adjusting the ratios/proportions of fuel types and mixture under the stress conditions. The expected result was to establish a basis for determining the ideal/optimal fuel-mix-stress ratios on the hybrid car＇s performance. Using the NXT robotics kit abstracted the low level details of the embedded system design, which allowed a focus on the high level design details of the research. Also, using the NXJ Java-based firmware allowed the incorporation of object oriented design principles into the project. The paper outlines the evolution and the compromises made in the choice of hardware and software components, and describes the computations and methodologies used in the project.

Experimental study on mechanical behavior of high performance concrete under multi-axial compressive stress

Experimental investigation was conducted to characterize the responses of high performance concrete(HPC) subjected to multiaxial compressive stresses. The HPC specimens were prepared with three different mix proportions, which corresponds to three different uniaxial compressive strengths. The cubic specimens with size of 100 mm for each edge were tested with servo-hydraulic actuators at different stress ratios. The principal stresses and strains of the specimens were recorded, and the failure of the cubic specimens under various stress states was examined. The experimental results indicated that the stress states and stress ratios had significant influence on the strength and deformation of HPC under biaxial and triaxial compression, especially under triaxial compression. Failure criteria were proposed for the HPC specimens under biaxial and triaxial compressive loading. The test results provided a valuable reference for obtaining multi-axial constitutive law for HPC.