共查询到20条相似文献，搜索用时 203 毫秒
1.
简述国内外在垃圾填埋场动力稳定机理及稳定分析方面的研究现状与最新进展，包括：1．垃圾土（MSW）与接触面的属性参数；2．垃圾土的本构模型；3．填埋场动力分析方法。 相似文献
2.
3.
4.
提高软土地基承载力方法的研究现状与展望 总被引：1，自引：0，他引：1
采用合理的软土地基处理方法,提高地基的承载力,这在建筑结构抗震设计中是十分重要的。如何控制软土地基的变形及提高承载力是地基基础工程中的一个关键技术问题。对国内外软土地基处理方法研究的进展进行了简要介绍,并提出了有关建议。 相似文献
5.
如何选取非岩性地基的处理方案对于不满足抗震适应性要求的核岛厂房地基而言具有重要的工程实用价值。结合国内某内陆核电不符合抗震适应性要求的实际厂址条件,给出地基处理方案评价的数值计算模型及分析过程。首先针对该核电工程实际项目,提出嵌岩桩、CFG桩及水泥土搅拌桩三种地基预处理方案,并以规范法验证处理后地基的承载力要求;进而通过建立非岩性地基条件下的桩-土-结构动力相互作用计算模型来综合考虑各方案对核岛厂房的地震响应影响,其中通过引入黏性人工边界和能量传递边界模拟无限地基辐射阻尼效应,采用等效线性法描述近场地基非线性特征,并基于上述有限元模型以全耦合方式考虑群桩效应的影响;最后从满足厂址地基适应性和经济效益两方面进行综合评价,给出针对本工程的最佳设计方案。该分析方法及研究成果可为类似条件下的核岛厂房非岩性地基处理方案的比选问题提供借鉴与参考。 相似文献
6.
合理有效地模拟桩-土-结构动力相互作用是软土地基条件下核岛厂房结构抗震适应性分析及地基处理的关键环节。以某拟建核岛厂房实际工程为研究背景,结合SuperFLUSH软件平台,以Goodman单元模拟桩与桩周土间的接触效应,采用等价线性法描述近场软土地基非线性特性,并在模型底部和侧面引入黏性边界模拟半无限地基辐射阻尼效应,从而建立土质地基条件下桩-土-核岛结构相互作用分析模型。进而,通过对原状地基和嵌岩桩处理地基条件下核岛厂房的楼层反应谱、结构节点相对位移（绝对值）的对比分析,探讨考虑桩-土间接触效应的嵌岩桩基对核岛厂房结构的影响规律。研究成果可为实际工程中类似土质地基条件下核岛厂房结构的地基处理提供参考。 相似文献
7.
8.
针对某湖滨路的拓宽改造工程,选取地基土层最不利的断面进行数值模拟,并采用强度折减法研究其整体稳定性。数值分析结果表明,加宽后的新路基稳定性较差,安全储备不能满足要求,需要采取加固措施。对初步设计提出的仅采用土工格栅和采用土工格栅＋水泥搅拌桩这两种不同加固处理方案进行了数值分析。计算结果表明,相比仅采用土工格栅,采用土工格栅＋水泥搅拌桩进行软基处理可以有效地减小不均匀沉降、提高路堤的整体稳定性。本文的实例研究可供类似工程参考和借鉴。 相似文献
9.
10.
高密度电法在茶园沟填埋场选址中的应用 总被引：1，自引：0，他引：1
填埋是废物处理的常用方式之一,同时也时刻威胁着人民生命财产安全.因此,填埋场的选址就更加需要引起重视.工作区大都被第四系覆盖,植被茂密,露头较少,给评估工作增加了较大的难度.与传统的电阻率法相比,高密度电法具有成本低,效率高,信息丰富,解释方便,勘探能力显著提高.本文应用高密度电法对茶园沟填埋场选址进行了详细的评估,调查结果显示,穿过该区的F_2、F_3断裂分别从填埋场的南端和北端穿过,未直接穿过填埋场,为填埋场提供了相对稳定的构造环境.地表的粘土层含水性较好,起到了天然隔水层的作用.通过高密度电法的使用,对填埋场的构造分布特征和水文地质特征有了初步的了解,对填埋场选址及后期工程的开展有良好的指导意义. 相似文献
11.
Effects of local site conditions on the seismic response of municipal solid waste landfills 总被引：3，自引：0，他引：3
P.N. Psarropoulos Y. Tsompanakis Y. Karabatsos 《Soil Dynamics and Earthquake Engineering》2007,27(6):553-563
Over the last decade, the seismic response of landfills made of municipal solid waste has drawn attention mainly due to the environmental and public-health issues that could be raised in the event of a failure. Nevertheless, there are several associated technical issues that have not been adequately investigated. One of these is the impact of local site conditions on the earthquake-induced accelerations and, thereby, on the seismic design of a landfill. This study presents the results of a parametric numerical simulation that has been performed in order to examine the effects of local site conditions on the dynamic response of a typical landfill. Emphasis is given on the special characteristics of ground motion, while the material nonlinearity of both soil and waste is taken into account by an equivalent-linear procedure. Results indicate that local site conditions may play a significant role in the seismic response of a landfill. However, this role cannot be judged a priori as beneficial or detrimental, as it depends not only on soil conditions and seismic excitation, but also on the material and geometric characteristics of the landfill. 相似文献
12.
《地震研究进展（英文）》2022,2(4):100174
The treatment of soft soil foundation under nuclear safety grade corridors with graded sand and gravel materials has a good development prospect. It is of great engineering value to explore the influence of construction parameters of graded sand and gravel foundation on the seismic response of gallery structures. Taking the safety grade underground corridor of a nuclear power plant as the engineering background, the equivalent linear method is used to consider the nonlinear dynamic characteristics of graded sand and gravel. The energy transfer boundary is applied at the truncation boundary to simulate the dissipation effect of scattered wave fluctuation energy and the ground motion input. The thicknessless contact element is introduced to consider the contact effect between the corridor structure and the graded sand and gravel foundation, so as to establish the calculation model of the dynamic interaction between the graded sand and gravel foundation and the corridor structure. Furthermore, the influence of the relative compactness and the foundation treatment depth on the seismic response of the corridor structure is studied, and the calculation results of the acceleration response spectrum and relative displacement of the corridor structure are analyzed. The calculation results show that the two construction parameters have different degrees of influence on the seismic response of corridor structure. The research results can provide reference for the engineering design and construction of underground corridors, and provide technical support for the application of graded gravel materials in soft soil foundation treatment. 相似文献
13.
为解决在膨胀土山区修建机场时跑道地基处理的问题,以安康地区膨胀土为研究对象,在对现行石灰改良膨胀土施工控制参数常用方法分析的基础上,进行膨胀土及石灰改良膨胀土的膨胀性能和强度的相关试验。研究结果表明:随着石灰掺量的增加,最优含水率增大,最大干密度减小,胀缩潜势呈降低趋势,石灰掺量与最大干密度呈非线性关系,在石灰掺量达到9%时有荷膨胀率变化的规律性很强;相同石灰掺量改良土的CBR与击实功、含水量等因素有关,并不随着压实系数增加而增大。掺加石灰的比例对石灰改良膨胀土的强度增长影响较大,石灰掺量9%时的CBR值明显大于其他掺量;相同压实系数下石灰掺量3%和6%改良膨胀土的压缩性比较接近,石灰掺量增加到9%时其压缩性明显降低。结合试验结果,提出用石灰改良膨胀土对跑道进行地基处理,并以膨胀性指标作为主要控制指标、强度指标作为验证指标来确定施工参数。 相似文献
14.
15.
Observations from many recent strong motion events have shown the importance of local soil conditions and non-linear soil behaviour on the seismic ground response (site effects). As demonstrated by previous seismic microzoning studies (Lebrun et al.) [1]), as well as by at least three historical major earthquakes, Pointe-à-Pitre is prone to strong site effects, due to the particular geology of the area. In this paper, we present a comparison between the strong-motion data available from the stations operating on the swampy site of Pointe-à-Pitre airport and the ground motions derived from 1D non-linear finite element simulations.Results show that, for moderate to strong ground motions, 1D simulations reproduce the main characteristics of site response in terms of duration, energy distribution, amplitude and frequency content. It also shows the importance of very superficial soft layers as peat or saturated mud in low frequency site effects simulations. This point is important for further engineering studies since such very soft formations overlain by stiffer landfills are commonly expected in the Antilles context. Our work also shows that Anderson's criteria, used to quantify the goodness-of-fit of simulated ground motions to the observed ones, appear to be an interesting diagnostic tool for testing the quality of numerical simulations from an engineering point of view. 相似文献
16.
2015年7月3日新疆皮山MS6.5级地震灾区地处塔里木盆地南缘,该地自然条件恶劣,经济极为落后,灾区农村的民房除了抗震安居工程建设的房屋外,还有大量抗震性能较差的民居,在地震中受损严重,经济损失较大。灾区大部分位于山前溢出带,地下水位浅、地基土层软弱等场地条件对地震动有放大作用,震害影响范围较大。灾后重建中应继续加大安居富民工程的经费投入力度。灾区北部人口密集,地基土层软弱,工程地质条件差,建议在今后的安居富民建设中加强地基处理。 相似文献
17.
Landfill is the most commonly used method for disposal of waste materials since it is one of the least expensive methods. In order to dispose of any hazardous material to a landfill, a liner is used, which protects the underlying land and groundwater since it acts as a barrier to fluid movement. Of the various methods available for providing improved and more effective properties of landfills, methods involving the use of bentonite, cement, lime, gypsum, etc., have been explored in the laboratory. The aim is to overcome the problem and deficiencies of the existing liners. It is observed from the experimental results that the metal concentrations of the input waste solution can be reduced to 80–98% using a soil‐cement admixture, 60–95% using a soil‐gypsum mixture, 45–95% using a soil‐bentonite mixture, 50–90% for soil, 35–80% using a soil‐lime mixture, as liner materials. The permeation rate of different metals through the different soil‐admixture media depends on various factors. A simple mathematical treatment of the phenomenon related to the permeation of liquid through the admixture of the clay and other components has been developed. The experimental results show satisfactory agreement with the predictions. 相似文献
18.
Electrical resistivity methods are widely used for environmental applications, and they are particularly useful for the characterization and monitoring of sites where the presence of contamination requires a thorough understanding of the location and movement of water, that can act as a carrier of solutes. One such application is landfill studies, where the strong electrical contrasts between waste, leachate and surrounding formations make electrical methods a nearly ideal tool for investigation. In spite of the advantages, however, electrical investigation of landfills poses also challenges, both logistical and interpretational. This paper presents the results of a study conducted on a dismissed landfill, close to the city of Corigliano d'Otranto, in the Apulia region (Southern Italy). The landfill is located in an abandoned quarry, that was subsequently re-utilized about thirty years ago as a site for urban waste disposal. The waste was thought to be more than 20 m thick, and the landfill bottom was expected to be confined with an HDPE (high-density poli-ethylene) liner. During the digging operations performed to build a nearby new landfill, leachate was found, triggering an in-depth investigation including also non-invasive methods. The principal goal was to verify whether the leachate is indeed confined, and to what extent, by the HDPE liner. We performed both surface electrical resistivity tomography (ERT) and mise-à-la-masse (MALM) surveys, facing the severe challenges posed by the rugged terrain of the abandoned quarry complex. A conductive body, probably associated with leachate, was found as deep as 40 m below the current landfill surface i.e. at a depth much larger than the expected 20 m thickness of waste. Given the logistical difficulties that limit the geometry of acquisition, we utilized synthetic forward modeling in order to confirm/dismiss interpretational hypotheses emerging from the ERT and MALM results. This integration between measurements and modeling helped narrow the alternative interpretations and strengthened the confidence in results, confirming the effectiveness of non-invasive methods in landfill investigation and the importance of modeling in the interpretation of geophysical results. 相似文献
19.
针对沙特吉赞新建的围海造陆货物堆场的地基处理,基于珊瑚礁砂的疏浚工程特性,开展了用两种振冲挤密法加固该处不良级配疏松礁砂地基的有效性及确定其相应工艺参数的现场试验。先完成选定小区试验,后由SPT检验其效果,再分析确定最优振冲工艺并指导了大面积工程施工。通过比对场区地基加固前、后的CPT检测结果,用Iwasaki液化指数法对振后地基做进一步液化判断,同时采用极限法(基于CPT)和施莫法(基于SPT)对加固地基进行了沉降分析并对比两种计算结果,验证本试验研究所确定的加填料振冲方案与施工工艺合理性,加固后地基的承载及抗液化能力得到有效提高且完全能满足工后沉降控制要求。研究成果可供珊瑚礁海域的类似工程参考或借鉴。 相似文献
20.
弦线模量法建立了考虑黄土基本物性指标及附加应力综合影响的弦线模量函数,应用分层总和法计算黄土地基的变形量,并在陕西关中黄土地区工程实践中获得良好的预测结果,而在分析兰州等其他黄土地区地基沉降时,结果出现偏差,究其原因,与计算中忽视了天然状态下黄土的结构性特征有关。以弦线模量法为基础,通过西安近郊4处土样试验和大量载荷试验资料,分析黄土的构度指标与压缩模量、孔隙比、含水量的关系,并将构度指标引入弦线模量表,深化结构性参数在地基沉降变形计算中的理论。 相似文献