压密注浆工艺在处理浜填土地基中的应用

通过对压密注浆工艺的技术和经济分析比较,并介绍该工艺在处理浜填土地基中的成功经验,从而得出压密注浆工艺是一种造价低、施工操作简便、周期短、加固效果良好的处理地基方法。     

瞬态瑞雷面波在压密注浆地基处理效果评价中的应用

目前,压密注浆处理软弱地基的质量检测方法以载荷板试验、标贯、轻便触探和静力触探为主,上述方法虽然精度较高但是难以用来进行普测.近期我们将瞬态瑞雷面波技术应用某工程压密注浆地基加固处理效果评价之中,取得了一定效果.     

高压旋喷注浆在危房地基加固中的应用

系统介绍高压旋喷注浆对危房软弱地基土加固处理效果,总结了设计施工的成功经验。     

静压注浆加固地基工程实录

本文介绍了广州市三元里某工程采用静压注浆形成树极状微型桩基加固软弱地基的设计思路及施工过程，根据注浆液在软弱土层中劈裂挤压及渗透作用，使所加固的软弱地基土载承力标准值ｆｋ≥４５０ｋＰａ，通过载荷试验等手段检查了本设计方案及施工工艺的可靠性，取得了良好的经济效益和社会效益。     

高压旋喷注浆加固地基工程施工工艺

高压旋喷注浆新技术,适用于砂类土、粘土、人工填土、淤泥等软弱地基加固处理.它可作为新建筑的地基加固,也可作为旧有建筑物的地基补强,防止基础渗漏等.由于这种方法具有设备简单、操作方     

地基处理优化技术的发展与应用

回顾了地基处理技术的应用发展史,将其大致分成压密固结法、换填垫层法、注浆加固法、复合地基法4大类,综述了各类地基处理优化技术的加固机理、施工工艺、加固优势等。重点介绍了这些地基处理技术的工程应用及其今后研究方向;阐明了我国地基处理优化技术的发展趋势。     

压密注浆在砂土液化处理中的应用

介绍了压密注浆法应用于安庆电厂地基液化处理的实践。通过现场检测资料的分析得出了压密注浆在处理液化地基的工程中可以达到设计要求，消除液化，提高地基土的承载力，而且在不便于大型施工机具进入的狭窄场所具有优越性的结论。     

SJP型浆材在地基加固中的应用

对贵城道路设施公司厂房地基不均匀沉降成因分析,认为地基承载力不足、地基土固结和地下水影响是主要原因,应采用以充填为主,渗透、压密劈裂联合作用的注浆加固方式进行地基加固。通过SJP注浆材料和纯水泥浆2种浆材的室内实验和工程注浆试验,证明SJP浆材具有初配流动性好、可灌性强、初凝与终凝时间可控等良好特性,用于大孔隙性、不均质地基的加固优于传统纯水泥浆,解决了普通水泥浆漏失量大、加固效果差或无法加固的问题。该加固工程采用SJP浆材注浆72个孔,消耗浆材173 m3,消耗水泥173 t,节约水泥约108 t,取得了很好的经济效益。     

振动挤密碎石桩处理可液化粉土地基试验研究

本文通过三种不同桩距振动挤密碎石桩处理软弱粉土地基的对比试验,试验了不同桩距振动挤密碎石桩的处理效果,并对振动挤密碎石桩中的一些问题作了试验研究。     

振冲碎石桩在地基处理中的应用

振冲碎石桩是近几年发展较快的软弱地基处理方法。通过对辽源污水处理厂A?/0反应池地基处理的应用,系统介绍了振冲碎石桩在施工过程中的机械及工艺流程。并就加固机理、施工方法以及实用效果几个方面进行了阐述。说明振冲碎石桩适用于松散砂土、粉土及淤泥质粉土地层,经过成孔、排污、清孔、填料、振密,最终控制成桩,可明显改善地基承载力,对软弱地基处理效果显著,具有一定的推广价值。     

Consolidation behavior of a soft mud treated with small cement content

Soft mud can be found in many large size reclaimed lands. Such soils present extremely high settlement potential that needs to be alleviated by means of effective ground improvement techniques. Current knowledge on applying small cement content to reduce settlement potential of soft mud is limited. This study concerns the consolidation behavior and settlement potential of soft mud treated with small cement content. Based on the pH values of soft mud–cement mixtures, oedometer specimens with cement content of 6% were prepared for consolidation tests. The test results show that preconsolidation pressure is rapidly developed and secondary compression is reduced. The ratio of secondary compression index to compression index is also reduced, indicating a change in grain size characteristics. The coefficient of consolidation is increased for consolidation pressures smaller than the preconsolidation pressure. This indicates that treating the soft mud with a small cement content can be very effective for reducing settlements in cases where new loads are small to medium and the time for ground improvement is limited.     

高速公路沿线暗浜填土的勘察和评价

目前，线路勘探中对浜填土检测不够重视或缺乏有效的方法，使浜填土的处理缺乏针对性，造成不必要的浪费或工程隐患。该文探讨了在线路勘探中暗浜的勘查技术及相应评价与整治方法。     

大冶铁山地区河流水体及水系沉积物中重金属元素分布特征

矿产资源的长期勘探、开采和冶炼活动给大冶铁山地区的自然生态环境造成了严重破坏.对该区西港河、东港河河水和水系沉积物中重金属元素分布特征的研究结果表明,该区矿山开采和冶炼活动形成的重金属污染元素主要为Cd、As、Zn;其主要污染源为冶炼厂排放的废水,其次是采矿废弃物堆积渗漏水;重金属元素在河水与水系沉积物中的空间分布特征较相似,但水系沉积物中元素质量分数比河水中的普遍增高,元素变化的剧烈程度加剧.     

真空加载方式对吹填流泥加固效果及土颗粒移动的影响研究

考虑加载方式的影响开展室内模型试验,对4组相同性质的泥浆试样（含水率为100%）分别采用不同的加载方式,即-80 kPa、-60 kPa→80 kPa、-40 kPa→-80 kPa、-20 kPa→-80 kPa进行加载,加载过程中对试样的出水量、沉降量和侧向变形进行跟踪监测,并对处理后土体的含水率、塑性指数和十字板剪切强度等的空间分布与变化规律进行研究。试验结果表明,（1）真空加载方式对吹填流泥的固结具有比较明显的影响;（2）初始真空荷载为-20 kPa时所得到的土体沉降量最大、强度最高,始终保持-80 kPa荷载情况下所得到的土体沉降量最小、强度最低;（3）从塑性指数的分布特征来看,土颗粒随着土中水的排出发生移动,初始真空荷载越大,这种趋势越明显,部分土颗粒会聚积在排水板周围而导致土体渗透性能的降低,严重时会影响土体的后续固结。建议在流泥淤泥的真空固结过程中采用低初始荷载方式进行加载。     

Multivariate analysis of heavy metal contents of sediments from Gumusler creek, Nigde, Turkey

In this study, heavy metal contents of samples from Gumusler creek in Turkey were studied and the metal contamination characteristics were investigated. In this respect, considering the pollutant sites in the area, systematic sediment samples were collected in a zone starting from the manifestation part of the water to the entrance of the Karasu creek in Gumusler town. Samples were taken from lower section of the river bed at 30 stations along Gumusler creek, 13 km in length and their heavy metal contents were analyzed with XRF Spectrometer. Correlation coefficients, element coefitic coefficient correlation, dendogram hierarchical cluster, model summary and Annova analysis statistical methods were applied to data. Strong positive correlations were determined for some elements which are believed to have possibly the same origin. In addition, mineralizations in the area are thought to cause variation in metal contents. Results of chemical analysis show that soil limit values and clark values were exceeded. The heavy metal accumulation in the creek is believed to be derived from non-operated Sb-Hg-W and Fe quarries.     

搅拌桩内套打钻孔灌注桩在暗浜深基坑围护工程中的应用

在暗浜地层内施工钻孔灌注桩时,易产生钻孔扩径、孔内塌方事故,产生“叉腿桩”及诱发搅拌桩次生“叉腿”,造成钻孔灌注桩与搅拌桩之间的产生大的缝隙.基坑开挖时,基坑外侧的地下水沿缝隙渗入,造成基坑外侧土体压缩变形,引起地表开裂、产生不均匀沉降.搅拌桩内套打钻孔灌注桩系先用低渗入量水泥将暗浜土搅拌成复合土,提高暗浜土的质量,然后在复合土内钻进成桩,其作用是避免钻孔灌注桩在暗浜土段的扩径、塌方超灌事故,确保了基坑桩基围护工程施工质量.     

Land subsidence caused by groundwater exploitation in Suzhou City,China

Suzhou City, located at the lower reaches of the Yangtze River in southeastern Jiangsu Province, is one of the few cities in China which suffer from severe ground settlement. A research project was carried out to investigate this problem. Geological and hydrogeological studies show that there is a multi-layered aquifer system with three distinct, soft mud layers of marine and lagoonal origins. An examination of historical records of groundwater extraction, water levels, and ground settlement shows that the ground subsidence is associated with the continuously increasing groundwater extraction in the deep, confined aquifer. It is believed that the consolidation of the soft mud layers, especially the third layer which is thick and close to the main pumped aquifer, contributes to the ground settlement. A three-dimensional finite difference numerical model representing the multi-layered aquifer system was developed to study the ground settlement in response to groundwater extraction. By calibrating the model with both the measured groundwater level and ground settlement, the aquifer parameters were estimated. The model outputs fit reasonably well with the observed results, which indicates that the numerical model can reproduce the dynamic processes of both groundwater flow and soil consolidation. The hydraulic conductivity of the third mud layer near the center of the ground settlement has been reduced by over 30% in the last 14 years. The gradual deterioration in the hydraulic conductivity of the mud may have significant adverse effect on the sustainable groundwater resource of the deep confined aquifer, since the recharge from the shallow aquifers through the mud layer is the only source of water to the deep aquifer. An analysis of the spatial distributions of groundwater drawdown and ground settlement shows that the area with maximum drawdown is not necessarily the area with maximum ground settlement due to the occurrence of the soft mud layer. A simple reallocation in pumping rates on the basis of the spatial distribution of the thick mud layer could significantly reduce the ground settlement. Electronic Publication     

开敞式潮滩-潮沟系统发育演变动力机制——Ⅰ.物理模型设计及潮沟形态

为研究潮沟发育演变动力机制,建立了以江苏中部粉砂淤泥质潮滩-潮沟系统为原型的降比尺物理模型,模拟在潮汐作用下,潮沟系统从平坦滩面逐渐形成、发育演变至动态平衡状态的过程,并分析了潮沟系统在不同阶段的形态特征。研究结果表明:潮沟系统发育速率先快后慢,最终达到动态平衡状态。采用潮沟发育各阶段潮沟系统的总长度与终态潮沟总长度的比值以及潮沟及其相邻处潮滩的高程变化速率两种方法,均可以衡量潮沟系统的发育程度。潮沟系统发育达到动态平衡后,各级潮沟个数占潮沟总数量的比例基本固定。潮沟的宽度、深度、宽深比均符合对数正态分布。潮沟的宽度与宽深比、深度与宽深比之间均具有幂函数关系。     

库内层状软土地基的联合处理方法研究

介绍了利用重锤夯实法加固表层填土与排水固结法加固深层软土联合处理库内层状软土地基的方法,在填土静荷载和塑料排水板作用下淤泥质软土很快完成主固结沉降,重锤夯实法使表层填土受到动力压密,软土和填土强度得以提高.试验结果表明,排水固结过程中填土层的单位沉降量远小于淤泥质软土,重锤夯实法的有效加固深度可以达到地表下3.5 m,影响深度可达6.0 m.联合采用两种地基处理方法可以有效提高层状地基承载力.     

废泥浆净化与固结方法的试验研究

动力总成液力悬置是国外７０年代末在汽车上开始应用的新型隔振元件，是国际汽车隔振技术的重大突破。由于它具有优良的动特性，可明显降低汽车振动和车内噪声，因而它取代传统的橡胶悬置是未来发展的必然趋势。本文回顾淳液力悬置的发展历史，对其进行了分类，阐述了各种典型的液力悬置的结构工作原理和性能特点及其发展趋势。