METHOD FOR IN SITU DETERMINATION OF Pco2 IN SEA-AIR EQUILIBRIUM SYSTEM

The method for determining Pco2 in the atmosphere and water by using gas chroma-tography was studied. For determination of Pco2 in the atmosphere, a sampling method was developed in which the chromatograph was connected to a 6-port valve with a sampling pipe opening to the atmosphere, so gas pressure in the sampling pipe was identical to that of the atmoesphere. A semi-automatic seawater-atmosphere equilibrium system was designed to determine the Pco2 in seawater. The equilibrium chamber contained in situ seawater and the well-equilibrated gas was pushed into the sampling pipe by sample wa-ter, so pressure and temperature calibration could be avoided. This method has high accuracy for the de-termination of Pco2 in the air and seawater, and was used for in situ determination of Pco2 in the atmo-sphere and of the seawater sample in the JGOFS cruise in the East China Sea.     

基于期望值模型的注水管网摩阻因数反演

为对油田注水管网摩阻因数进行反演求解,将注水管网节点部分未知压力设为随机参数,建立注水管网管道摩阻因数反演的一类随机优化模型———期望值模型;给出利用随机模拟技术和遗传算法求解期望值优化模型的数值方法.通过对理想注水管网进行反演求解,验证模型的合理性和算法的可行性.     

延庆台五里营井泄流管憋气的影响及解决

延庆台五里营井动水位自2010年7月3日起,出现每日上下近50 cm的波动,气汞、气氡同时出现异常.经分析,此异常变化是由于该井泄流管最高端憋气造成.在泄流管最高点处开口排气,成功地解决了因泄流管憋气造成的干扰问题.     

An improved siphon drainage method for slope stabilization

The siphon drainage is an effective measure for the slope groundwater control. However,for the traditional siphon drainage, limitations such as siphon lift restriction and poor reliability in longterm service prevent it from being widely used. In this study, an improved siphon drainage method with inclined borehole penetrating the deep part of the slope is proposed to overcome the limitations suffered by the traditional method. Through experimental research, theoretical analysis and engineering practice,the reliability and capability of the proposed method are investigated. The results demonstrate that with the inclined pipe the height difference between the control point of the groundwater level and the orifice can be controlled to be less than the height of the water column corresponding to the local atmospheric pressure. As a result, deep drainage can be achieved.In addition, by controlling the diameter of siphon drainage pipe not larger than 4 mm, a plug flow can be formed in the siphon pipe, which can prevent air accumulation in the siphon process and a continuous and effective siphon drainage is achieved. Through a practical project running smoothly since September 2013, it is found that the proposed method can effectively drain the groundwater deep in the slope and the maximum drawdown of groundwater level in boreholes can reach 8.5 m with an average drainage flow of 5.5 m3/d. The practical results also illustrate that 4 mm siphon pipe can be used to realize deep slope drainage and restart siphon automatically.     

大直径深埋顶管施工对地表沉降的影响

顶管施工因非开挖或少开挖而在城市建设中应用广泛, 但顶管施工引起的地表沉降不容忽视。依托佛山市某电力隧道顶管工程, 通过现场实测、数值模拟及Peck经验公式的方法研究了顶管施工引起的地表沉降规律, 探讨了管-土摩擦、注浆压力及支护压力对地表沉降的影响。结果表明: 顶管施工引起的横向地表沉降在距轴线约4倍管径范围内变化较大, 管-土摩擦的改变对横向地表距轴线约3倍管径范围内的地表沉降影响较大, 对纵向地表距开挖面约1倍管径范围内的地表沉降影响较小; 注浆压力的增大能够抑制地表沉降; 支护压力的改变对横向地表距轴线约2倍管径范围内的地表沉降影响较大。研究结果可为控制顶管施工引起地表沉降措施的制定提供参考; 同时, 实测值、模拟值及Peck经验公式所得到的地表沉降变化趋势和大小相近, 验证了数值模拟及Peck经验公式在实际工程中预测地表沉降的可行性。      

Modeling and Simulating for TSHD’s Swell Compensator by ADAMS

1 Introduction Today, maneuvering the draghead of a trailing suction hopper dredger (TSHD) on a predetermined spot is an operation that demands an increasing degree of accuracy (Cornelis, 1983). As a self-propelled, self-loading and self-discharging seagoing or inland waterway vessel with one or more flexible suction pipes equipped with special dragheads, the TSHD has a wide application area and is therefore called the workhorse of the dredging industry (Ni, 2004). The swell compensator, c…     

Modeling and simulating for TSHD’s swell compensator by ADAMS

CHC Trailing suction hopper dredgers (TSHD) have been widely used in dredging industry. In order to simulate the dredging process accurately, a mathematical model for a swell compensator used in TSHD is proposed, and a friendly simulation model based on the Automated Dynamic Analysis of Mechanical Systems (ADAMS) is built to test and validate the mathematical model for the swell compensator. The factors influencing the dynamic behavior of the TSHD suction pipe system, such as the motion of the vessel in an unquiet situation with different water current velocities, seabed profiles, seabed soil hardness and the forces acting on the suction pipe system, have been taken into consideration. The simulation results show that they fit in with the operating practice qualitatively.     

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郭庄煤矿七采区北翼自流排水管路选型及计算

郭庄煤矿七采区北翼涌水点标高-94m,排水管出水口标高-143m,涌水口与出水口垂直落差49m。根据流体力学知识,计算得出排水管路的扬程损失小于49m,满足水自流要求,安设煤矿井下用聚氯乙烯型排水管路两趟,实现绿色、环保、节能排水。     

浅层地热能开发利用地质环境影响与监测系统建设研究

浅层地热能的开发利用能取得的环境、社会和经济效益显著,已被社会广泛认可。但它的开发利用是通过热泵系统,从地质体中汲取地温资源与建筑物间进行能量交换,必然打破地质环境的自然生态平衡。该文分析了地源热泵工程对岩土体和地下水的温度、地下水水位、水质、微生物生存环境等产生的影响。介绍了地质环境监测系统建设内容,包括前端数据采集系统、数据传输系统和控制系统,重点介绍了地埋管和地下水2种不同换热方式热泵工程各自前端数据采集系统中地质环境监测点(孔)平面布置位置和数量、垂向上监测仪器的深度和间隔距离、主要的监测项目、监测精度、频率要求,以及利用监测数据可进行分析的内容等。