外加剂对改善镁水泥抗水性能的研究          下载免费PDF全文

宋明礼  孙庆国 《盐湖研究》1993,1(4):71-74

本文介绍了磷酸盐复合外加剂对镁水泥抗水性能的改善,并初步探讨外加剂对改善镁水泥抗水性能的机制。  相似文献   

废泥浆的固化及合理利用   总被引：3，自引：1，他引：3       下载免费PDF全文

费立  朱宗培 《探矿工程》1994,(4):40-42

采用固化法对废泥浆进行处理，以水泥做固化剂，加入其它处理剂，在室内进行了试验，选择出合适的配方，并在现场进行了初步试验。  相似文献   

微硅粉(纳米硅)水泥注浆技术在地质灾害防治中的应用          下载免费PDF全文

杜嘉鸿  陈兰云  王杰  王述红 《探矿工程》2005,32(1):35-38

介绍了微硅粉(纳米硅)浆材的基本性能，应用微硅粉浆材处理基础的不均匀沉降等地质灾害，解决了工程实际问题。  相似文献   

软土深层搅拌桩的水泥土抗腐蚀性室内试验   总被引：10，自引：0，他引：10  

黄汉盛  鄢泰宁  兰凯 《地质科技情报》2005,24(Z1):85-88

结合深港西部通道填海区深层搅拌桩在滨海地下水环境中施工的需要,对水泥土在自来水、地下水、海水及Na2SO4溶液环境下的抗腐蚀性进行了室内研究,研究表明以纯水泥为固化剂的水泥土在腐蚀性地下水环境中的抗腐蚀性能较差,增加矿渣、粉煤灰的含量,能增强水泥土抗腐蚀性;分析了固化剂中矿渣、粉煤灰掺入量对水泥土抗压强度及抗腐蚀性的影响规律,即固化剂掺入比不变的情况下,用矿渣、粉煤灰替代部分水泥能大幅度提高水泥土的抗压强度,同时改善其抗腐蚀性;得出了抗腐蚀性能良好的水泥土配方,即矿渣、粉煤灰的质量占固化剂的40%～60%,可供同类工程借鉴.  相似文献   

Effect of Cement Type on the Mechanical Behavior of a Gravely Sand   总被引：1，自引：0，他引：1  

S. M. Haeri  A. Hamidi  S. M. Hosseini  E. Asghari  D. G. Toll 《Geotechnical and Geological Engineering》2006,24(2):335-360

The behavior of a cemented gravely sand was studied using triaxial compression tests. Gypsum, Portland cement and lime were used as the cementing agents in sample preparation. The samples with different cement types were compared in equal cement contents. Three cement contents of 1.5%, 3.0% and 4.5% were selected for sample preparation. Drained and undrained triaxial compression tests were conducted in a range of confining pressures from 25 kPa to 500 kPa. Failure modes, shear strength, stress–strain behavior, volume and pore pressure changes were considered. The gypsum cement induced the highest brittleness in soil among three cement types while the Portland cement was found to be the most ductile cementing agent. In lower cement contents and lower confining pressures the soil cemented with Portland cement showed the highest shear strength. However, in the same range of cement content, the soil cemented with gypsum showed highest shear strength for highest tested confining stress. For higher cement contents the shear strength of soil cemented with Portland cement is higher than that for the two other cement types for the range of confining pressures tested in the present study. The samples cemented with lime had the least peak and ultimate shear strength and the highest pore pressure generation in undrained tests. Contrary to the soil cemented with lime, the brittleness of soil cemented with gypsum and Portland cement reduces in undrained condition. Finally it was found that the effect of cement type on the shear strength of cemented soils is more profound in drained condition compared to undrained state.  相似文献   

粘土水泥固化浆液在某垃圾卫生填埋场防渗帷幕注浆工程中的应用     

周立新 《化工矿产地质》2006,28(4):251-254

城市垃圾卫生填埋场对防渗帷幕注浆的要求较高,单纯的水泥注浆,由于水泥颗粒较粗、水泥浆液凝固时的析水率较高、水泥固结体抗酸稳定性较差,很难满足设计对防渗的要求．采用粘土水泥固化浆液相关性能均能满足垃圾填埋场防渗帷幕的要求。在长沙市垃圾卫生填埋场中应用实践行之有效,为此类帷幕注浆工程提供了一种较好的注浆方法。  相似文献   

固底管桩单桩承载力的研究     

李连营  白牧  赵志峰 《岩土工程技术》2006,20(4):163-165,169

通过现场对预应力管桩底部采用高压旋喷法进行加固这一新的施工工艺试验,探讨预应力管桩桩端为水泥土情况下的受力机理及提高管桩端阻力和单桩极限承载力的效果,并探讨其在天津地区的适用性。  相似文献   

Biomineralization in Agglutinating Foraminifera: An Analytical SEM Investigation of External Wall Composition in Three Small Test Forms     

Miriam A Bertram  James P Cowen 《Aquatic Geochemistry》1998,4(3-4):455-468

The walls of many deep-sea foraminiferal tests containabiogenic and biogenic, precipitated and agglutinated,components. Both environmental and genetic factorscan contribute to the great diversity in test form andcomposition in benthic foraminifera. Yet, smallspecimen size and the remoteness of the deep-seaenvironment have limited our ability to describe therelative influence of these biological and chemicalfactors. The use of fossilized foraminiferal tests aspaleo-indicators requires that we understand thecontrols on test composition. Test wall morphologyand composition were examined inforaminifera that colonized experimental substratesdeployed on a seamount in the central North Pacific. Three types of agglutinated forms were identified. Atriserial (Eggerella-like) and two-chambered(Hyperammina-like) form contained a Ca-rich(CaCO3) precipitate and the chamber walls of anencrusting two-chambered form was Ba-rich(BaSO4). We discuss the composition of thesebiologically precipitated minerals in the context ofthe environmental conditions during the life of theseforaminifera.  相似文献   

注浆法加固剥山填海地基          下载免费PDF全文

杜嘉鸿  王杰  陈兰云  魏德华 《探矿工程》1998,(6):11-12,17

分析了剥山填海地基上建筑物产生严重不均匀沉降的原因,介绍了采用注浆法对其进行处理的设计与施工。  相似文献   

膨胀土干缩变形特性试验研究   总被引：1，自引：0，他引：1  

王东伟  唐朝生  李胜杰  曾浩  施斌  张必勇 《高校地质学报》1997,25(5):756

膨胀土是一种典型的问题性土，对气候变化非常敏感，在干旱气候条件下，极易发生体积收缩变形，引发各种工 程地质问题。为了研究膨胀土的干缩变形特性，开展了一系列室内干燥试验，测定了膨胀土的收缩特征曲线，重点分析 了初始含水率和干密度对干缩变形过程的影响，并进一步探讨了水泥固化抑制膨胀土干缩变形的效果和机理。结果表 明：（1） 膨胀土的干缩变形过程存在三个典型阶段：正常收缩、残余收缩和零收缩；（2） 初始含水率越高，试样蒸发速 率越快，且干缩变形完全后试样孔隙比越小而最终收缩应变越大，干缩变形越明显；（3） 初始干密度越大，试样蒸发速 率和最终体积收缩应变越小，提高初始干密度对试样干缩变形具有一定的抑制作用；（4） 在膨胀土中掺入适量的水泥能 显著降低试样的体积收缩应变，对干缩变形具有良好的抑制效果；（5） 膨胀土的干缩变形具有明显的各向异性特征，并 且与初始状态有关。  相似文献