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1.
刘彪 《科技和产业》2022,22(8):336-343
直径不小于2 000 mm的灌注桩钻进入硬岩地层遇存在倾斜岩面或岩体完整性差存在发育裂隙、破碎带等情况时,研究制作上扶正、下扶正两款新型钻头。通过在旋挖钻头上增加上扶正、下扶正结构,进行导向,逐级扩孔钻进,使钻头整体受到侧向支撑约束,从而对硬岩中钻进的钻头进行精准定位,确保了钻孔垂直度,有效克服岩体破碎或倾斜岩面出现的偏孔问题,减少问题解决成本,降低问题处理难度。  相似文献   

2.
孟景凤 《魅力中国》2014,(8):350-350
井筒施工过程中,根据地质备件揭露的岩性判断为井筒处于构造破碎带,突水涌水量由62m3/h逐渐增大到92m3/h,严重影响井筒掘进,经过深入研究和多种方案对比研究,确定长钻密集孔结合短钻的预注浆方案,取得良好效果,最终顺利通过含水层。  相似文献   

3.
石灰岩地区往往石芽、溶洞、土洞、溶沟、溶槽等岩溶现象发育,其出现的位置、深度及大小等变化无常,在桩基施工容易出现"滑桩"、"悬桩"、"半悬桩"等工程质量问题,在荷载作用下,可能产生桩基失稳现象。因此,对于岩溶区的工程嵌岩端承桩位必须进行超前钻探以探明桩端底下3倍桩径深度范围内有无溶洞、破碎带、软弱夹层等不良地质条件。而岩溶发育区桩基施工难度很大,质量要求很高,易导致施工事故频发,如何更好地利用超前钻探资料为设计与施工服务亦显得尤为重要。  相似文献   

4.
提出了一种R11发泡的聚氨酯硬泡沫废弃物的环保处理工艺,探讨了相关的工艺参数计算问题,以及在年拆解10万台废弃电冰箱项目的聚氨酯硬泡沫处理系统的规划设计中进行了应用。处理工艺路线包括泡沫粉碎、发泡剂蒸发、混合气收集、除尘、储气、压缩、冷凝、节流以及发泡剂与空气的分离。工艺参数计算主要涉及主要工艺环节的热力学计算,包括破碎后的泡沫中的R11发泡剂的蒸发吸热、混舍气压缩功耗、冷凝过程的散热。本处理工艺解决了泡沫处理过程中发泡剂的回收问题,具有处理过程中耗能低、发泡剂分离回收效果好的优点。  相似文献   

5.
针对低透突出煤层抽采钻孔钻进、冲孔效率低和人员投入大的问题,以车集煤矿为试验地点,采用理论分析与现场试验的方法,分析自动化钻冲造穴卸压增透装备性能.结果表明:自动化钻冲造穴装备平均每米的钻进速度、冲孔速度、退钻速度分别是普通打钻冲孔装备的1.59、1.36、0.72倍,单机综合作业效率和人均作业效率分别是普通打钻冲孔设备的1.3、3.9倍.水射流在钻孔煤段破冲出了直径约为0.8~1 m的孔洞,为煤体形变提供了空间.较普通穿层钻孔,冲孔钻孔瓦斯流量衰减周期提高了2~4倍.  相似文献   

6.
本试验以新型定型材料——石蜡微胶囊为蓄热主体,泡沫金属作为传热材料及骨架结构,将石蜡微胶囊粉末填充在泡沫金属孔隙内。对纯石蜡微胶囊和泡沫金属与石蜡微胶囊复合相变材料蓄热热性能进行试验对比研究,结果表明,泡沫金属可以加强传热,提高相变材料的蓄热能力,其中泡沫金属铜的传热效果较好。  相似文献   

7.
以青岛地铁2号线盾构隧道下穿既有胶济铁路为背景,采用三维数值模拟方法研究胶济铁路路基的沉降规律和变形控制。首先针对工程存在破碎带的情况,分析盾构穿越破碎带对铁路路基沉降的影响。然后考虑青岛上软下硬地层的特点,分别采用上部土层注浆加固和下部岩层全断面帷幕注浆加固方案,研究不同加固方案对盾构下穿既有铁路路基的变形控制效果。研究结果表明: 盾构穿越破碎带区段时铁路路基沉降偏大,施工存在安全风险,影响胶济铁路的安全运营;地层加固后路基的沉降相较于地层未进行加固有明显的降低,上部土层注浆加固使路基沉降值降低了约40%,全断面帷幕注浆加固使路基沉降值降低了约65%,同时下部岩层加固相较于上部土层注浆加固对路基变形控制更加显著;地层加固后TBM下穿施工对铁路路基的影响减小,能够确保胶济铁路的正常运营。  相似文献   

8.
熊逸凡 《科技和产业》2023,23(6):239-248
立足于城市地铁盾构施工掘进过程,旨在预防地下岩溶发育并存在断层破碎带的城市中地铁盾构施工面临的突水涌泥灾害风险。针对城市地铁建设过程中盾构隧道前方断层破碎带临界安全距离问题,研究不同类型与直径的盾构机刀盘、不同厚度与水压的前方断层破碎带对临界安全距离的影响规律与响应敏感程度。利用COMSOL Multiphysics软件流固耦合方法模拟盾构推进过程与突水发生时刻。综合三维有限元数值模拟结果,利用SPSS Statistics软件中的多元回归功能得到盾构隧道前方断层破碎带临界安全距离公式。研究结果对于断层破碎带发育及地下水丰富的城市地铁盾构开挖工程具有一定的施工指导意义。  相似文献   

9.
赵毅 《科技和产业》2020,20(9):207-212
以滇中引水工程大理I段香炉山隧洞某施工隧洞为例,详细阐述了施工段的地质情况和隧道开挖过程中所遇到的塌方及涌水地质灾害概况。综合考虑施工进度与安全,通过对灾害的机理研究、现场试验、方案优化,提出应对灾害的关键施工技术。在断层破碎带不良地质洞施工,采用“管超前、短进尺、强支护、早封闭”;在富水破碎带洞段,采用“先探后掘,以堵为主、堵排结合”的施工原则,优化确定掌子面帷幕超前注浆的施工技术。成果在现场得到成功验证,保证了隧洞的安全掘进。  相似文献   

10.
卢志强  杨敏 《科技和产业》2023,23(19):210-217
顺北油气田奥陶系目的层埋深普遍在8 000 m左右,三维地震资料采集面元25 m×25 m,地震资料分辨率较低,导致顺北油气田奥陶系鹰山组断控体油气藏难以精细刻画与表征。结合常规测井、电成像、远探测、取芯等资料,开展不同应力作用下断控体结构分析、断控体油气藏破碎裂缝带、破碎角砾带、断裂空腔分布研究。结果表明:断控体油气藏主要储集空间来自多期构造活动叠加改造形成的断裂空腔、角砾间孔隙、构造裂缝,不同应力机制决定断控体的发育程度,拉张背景易形成断裂空腔及裂缝带,挤压背景易形成破碎角砾带及裂缝带;断控体常发育典型的核带结构,裂缝带的宽度范围较大(0.35~1.64 km),且分布范围广,角砾带的宽度范围次之(0.44~0.93 km),且分布范围中等,断裂空腔的宽度范围最小(0.25~0.35 km),且分布范围小,主要集中在局部拉张应力区。  相似文献   

11.
The bio-control potential of rhizospere bacteria Pseudomonas fluorescens against plant-parasite nematode had been demonstrated. P. fluorescens had shown the effect to enhance tobacco resistance to root-knot nematode Meloidogyne incognita. Inoculation with P. fluoreseens in tobacco could lead to significant reductions in the number of juveniles that penetrated tobacco root and further life stage development of the juveniles. The number of juveniles penetrated into tobac- co root in treatment with P. fluorescens is significantly different from CK at 2DAI, 6DAI, 8DAI and 10DAI. Significant reduction and delayed development of juveniles that penetrated into tobacco root and treated were observed in treatment at 14DAI, 21DAI, 28DAI and 35DAI. In addition, P. fluoreseens treatment leads to a significant reduction in the number of eggs per egg-mass at 35 DAI. The results show P. fluorescens induced a continuously suppression on root-knot nema- tode M. incognita throughout their entire early infection phase of root penetration, subsequent life stage development and reproduction.  相似文献   

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14.
利用膜技术回收利用碱性废水研究进展   总被引:1,自引:0,他引:1  
回顾了利用膜分离技术处理碱性废水的工艺与综合利用技术所取得的丰硕成果,总结了各种治理方法的特点、适用性及发展方向。  相似文献   

15.
Indonesia’s economic growth picked up slightly in mid-2016 but remains below the level demanded by government and popular aspirations. Despite a plethora of reforms intended to increase efficiency and productivity, some policies are perverse and longstanding problems of implementation remain. The share of manufacturing has declined, the real exchange rate has appreciated, exports have dwindled, and growth has been trending downwards. The banking sector is stable but inefficient, with wide net interest margins and numerous barriers to competition. Trade protection, particularly in basic food commodities, has created high costs that weigh particularly heavily on the poor. Declining government revenues have placed increasing pressure on the public budget, even as the current administration aims to increase spending on infrastructure and welfare and to enhance productivity. In an effort to increase revenues, the government has announced a tax amnesty program and other measures. In addition, Sri Mulyani Indrawati, the new finance minister, has taken steps to cut non-essential expenditure in order to secure high spending on infrastructure and at the same time keep within the 3% budget deficit limit stipulated by law. Although the overall debt situation is not yet alarming, declining revenues and budget cuts that do not fully reflect this decline are putting pressure on increasing debt levels. The government’s high-profile tax amnesty program was the major policy initiative implemented in the second half of 2016 that aimed to relieve this pressure. Despite widespread criticism of, and scepticism about, the tax amnesty (both within and outside Indonesia), its first phase had a much higher participation rate than most independent accounts expected. Revenues raised so far through the amnesty are less than 60% of the official target, but this is actually a strong result for the short term. The bigger question, however, is whether the amnesty is a key element of a more encompassing strategy to overhaul the system of taxation and tax administration.  相似文献   

16.
In this paper, I analyze the causes of the prolonged slowdown of the Japanese economy in the 1990s and find that the stagnation of investment, especially private fixed investment, was the primary culprit. I then investigate the causes of the stagnation of household consumption during the 1990s and find that the stagnation of household disposable income, the decline in household wealth, and increased uncertainty about the future are among the contributing factors. Finally, I consider whether demand side factors or supply side factors were more important as causes of the prolonged slowdown of the Japanese economy in the 1990s and conclude that the former (especially misguided government policies) were probably more important.  相似文献   

17.
余中元 《特区经济》2010,(1):148-150
天文旅游资源从成因可以分为行星地球天文旅游资源、天体天文旅游资源和天文文化旅游资源三类。天文旅游方兴未艾,我国天文旅游具有很大发展前景。文章对我国开展天文旅游的条件进行了分析,对发展天文旅游的策略和措施进行了梳理。  相似文献   

18.
周兢 《特区经济》2010,(6):123-125
城市社会在对农民的开放与封闭之中徘徊。改革开放后城市社会对农民的开放已经使很多农民城市化。城市社会对农民的封闭已由政策性封闭转向经济性封闭。城市社会对农民的封闭增加了农民城市化的成本和社会风险。必须加强城市社会对农民的开放,逐步消除对农民的封闭政策,以推进农民的城市化。  相似文献   

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张冬 《特区经济》2007,(5):98-99
信息化时代中美商学院图书馆的建设与发展,成为当今时代高等商学教育发展与进步的一个重要环节,对中美四大商学院图书馆的发展状况、差距进行分析比较,对促进我国商学院图书馆事业的改革、建设和发展具有一定的启示作用和参考价值。  相似文献   

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