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1.
Effect of Cement and Quarry Dust on Shear Strength and Hydraulic Characteristics of Lithomargic Clay
The lithomargic clay constitutes an important group of residual soils existing under lateritic soils. This soil is found on
the western and eastern coasts of India over large areas. This soil is a problematic one and is very sensitive to water and
loses a greater part of its strength when becomes saturated. These high silt deposits have invited many problems such as slope
failures, foundation failures, embankment failures, uneven settlements etc. In this investigation an attempt is made to study
the effect of cement and quarry dust on shear strength and hydraulic characteristics of the lithomargic clay after the stabilization.
Microfabric and mineralogical studies were carried out to find out the reason for the strength development of the stabilized
soil using SEM and XRD analysis. The results indicated that there is an improvement in the properties of the lithomargic clay
with the addition of cement and quarry dust. The XRD results indicated the formation of CSH and CAH, which are responsible
for strength development in the stabilized soil. 相似文献
2.
This study examines the stability of an embankment used in stone quarry reclamation built of local natural soil mixed with stone dust. Stone dust is a fine-grained and low-strength material, whereas soil is coarser with higher strength. Test results show that the shear strength and maximum dry unit weight of the mixed material increase with a decrease in the stone dust. After reviewing various domestic and international standards for slope stability, this study suggests a three-grade slope stability rating system (“unstable,” “requires attention” and “stable”) for embankments built of soil mixed with stone dust. A series of slope stability analysis aims to define stable heights, slope angles and mix ratios for such embankments. Safe slope gradients should be 1:1.8 or higher for 10 m high embankments. Embankments 15 m in height should use a mix ratio less than 50% and a slope gradient of 1:1.8 or higher. The safe dimensioning and design guideline values determined by this study should be useful for the construction of new, as well as the stability evaluation of existing embankments that have been made from mixed soils containing stone dust. 相似文献
3.
Flowable fill is a self-levelling and self-compacting, cementitious material which is primarily used as a backfill. It is
a mixture of fine aggregates, small amount of cement, water and a by-product material. In this present experimental study,
three industrial by-products namely fly ash, rice husk ash and quarry dust were used as constituent materials in flowable
fill. Mix proportions were developed for different combination of these industrial by-products, in addition to small amount
of cement content. The main objective of the present investigation is to study the stress–strain behaviour of these mixes,
namely unconfined compressive strength (UCS), strain corresponding to peak stress, strain corresponding to fracture and modulus
of elasticity. In addition, several mixes were tested for few other properties such as flowability, density, water-absorption
and volume changes. The range of strengths, strains and moduli of elasticity obtained for these flowable fill mixtures represents
different types of clay soils ranging from soft clays to very stiff clays. Thus, industrial by-products such as fly ash, rice
husk ash and quarry dust can be beneficially added in flowable fill that offers comparable strengths to soils used for conventional
fills and many other low-strength applications. 相似文献
4.
Black Sea coast line is a hazardous region especially in winter due to the dominant wave action. Therefore, rubble mound breakwaters protected with armourstone used as ship shelters are vital structures especially for the fishermen. The deterioration of the armourstone with time in the form of abrasion and disintegration may result in the failure of the breakwater. In this study, the properties of the armourstone taken from an andesite quarry and used in the Hisarönü rubble mound breakwater were studied both in field and laboratory in order to assess their qualities and long-term durabilities. Based on the in situ observations and laboratory tests, the andesite is found to be generally marginal rock. CIRIA/CUR, RDIs, RERS and Wet-Dry strength ratio classifications are in good agreement with the in situ observations and the results of the laboratory tests. However, RDId, Average Pore Diameter and Saturation Coefficient classifications cannot correctly predict long-term durability of the armourstone. Field studies reveal that block size of the andesite in the quarry increases with depth due to the increase in spacing of the cooling joints of the rock. 相似文献
5.
Zhan Liang-tong Guo Xiao-gang Sun Qian-qian Chen Yun-min Chen Zu-yu 《Acta Geotechnica》2021,16(4):1247-1263
The 2015 catastrophic landslide in a 110-m-high waste dump in Shenzhen is recognized as one of the largest landfill failure worldwide. An earlier comprehensive field investigation revealed that the dominant component of the fill was completely decomposed granite (CDG), and the dumping operation was accompanied by a rise of the groundwater level. In this paper, the complex stress paths for the initially unsaturated fill materials being subjected to both rapid filling and wetting were investigated. A simplified method was proposed for estimating the gain of undrained shear strength under the complex stress paths. Soil samples were taken from the site to a laboratory to measure the undrained shear strength and validate the estimation method. Total stress-based stability analyses were carried out to calculate the factor of safety of the dump at failure. The triggering mechanism of the landslide is clarified as follows: The gain of shear strength with the surcharge loading for the wet layer in the lower part of the waste dump was limited by a build-up of excess pore-water pressure. The gain of shear strength for the relatively dry fill material was attenuated with the rise of groundwater level. When the shear strength was not enough to resist the increasing slip force with the surcharge loading, a deep-seated translational failure took place in the lower wet layer of the waste dump. The proposed method for analyses of undrained strength and slope stability are proven to be applicable to the waste-dumping operation with rapid filling and rising groundwater level.
相似文献6.
排土场稳定性主要取决于排土场的坡角及排弃废石的内部强度。通过低压到高压的三轴压缩试验研究了千枚岩粗颗粒散体材料强度的特性及压力对其强度的影响。试验表明：粗颗粒材料的破碎率随着压力的增大而增加,而增加速率则随着压力的增大而减小,并给出了一个用于描述压力及破碎率的关系式。提出了考虑破碎对强度影响的强度准则,该准则能描述粗颗粒材料的强度随压力的变化情况。采用该强度准则分析排土场的稳定性,其结果更加接近实际情况。而采用摩尔-库仑强度准则计算得到的排土场稳定性安全系数偏大,存在安全隐患。建议采用本文提出的强度准则分析排土场稳定性,特别是对于超高排土场的稳定性分析,更加适用该强度准则。 相似文献
7.
C. Albarrán-Liso M. M. Jordán-Vidal T. Sanfeliu-Montolio M. J. Liso-Rubio 《Environmental Geology》2006,49(7):1043-1050
The necessity of eliminating debris from a granite quarry has awakened an interest in applications of by-products, called
“marginal arids”, in different fields, like construction and foundations for roadways, restoration, material for the manufacture
of artificial rocks, and artesian products etc. Conclusions obtained from the results of tests carried out by X-ray diffraction
of granite quarry by-products in Extremadura, Spain, submitted to different treatments, are established. Test pieces from
two quarries are analyzed and compared generally and specifically, for commercial use. Finally, conclusions relating to essays
in test pieces and mineral dynamics of marginal arid granite are exposed. 相似文献
8.
Mahmoud Ghazavi 《Geotechnical and Geological Engineering》2004,22(3):401-416
Waste materials such as waste tires, rubbers, and plastic materials are normally produced in every society, entering the environment
and causing serious problems. These problems may be somehow reduced by finding applications for them in engineering, for example,
as lightweight materials for backfill in geotechnical projects. To this aim, this paper demonstrates how shear strength characteristics
of sand mixed with various percentages of waste garden hose grains are altered. A relatively, uniform sand has been mixed
with waste hose grains in loose and slightly compacted states. Waste hose grains were prepared with special popular machinery
in a local area. Various sand-rubber mixtures having 0%, 10%, 15%, 20%, 50%, 70%, and 100% waste hose particles by weight
were chosen. The rubber grains were distributed in the sand such that uniform mixtures are obtained. In order to compare the
shear strength of different sand-rubber samples, two compaction states were considered. The results show that the influencing
parameters on shear strength characteristics of sand-rubber mixtures are normal stress, mixture unit weight, and rubber content.
With the selected waste hose particles, compaction states, and rubber contents, the initial friction angle φ1 does not change significantly. However, an apparent cohesion appears in the mixtures. From environmental point of view and
due to lightweight material for the sand-waste hose particles, it may be useful to use such materials in corresponding geotechnical
projects.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
G. Iabichino M. Barbero M. Cravero C. Fidelibus G. Usai 《Environmental Earth Sciences》2014,71(7):3259-3271
The large dumps of waste material called ravaneti from marble quarrying activities in Alpi Apuane basin are distinguished features of the local landscape. They are strongly heterogeneous, never compacted and frequently subject to local instabilities. The access roads to the marble quarries cross the dumps; therefore, it is concern of the local authorities to hinder such phenomena. In this respect it is of paramount importance to evaluate the shear strength of the material comprising the dumps at the proper scale. In this note, the results of in-situ direct shear and tilt tests on samples of metric size are illustrated, together with the interpretation according to a strength criterion relative to rockfills. The results of a series of lab tests on the finer fraction of the waste material are also described and interpreted. Finally, qualitative considerations on the local and global stability of the waste dumps, related to their shear strength, are reported. 相似文献
10.
Ahmed AbdelRazek Rami M El-Sherbiny Hani A Lotfi 《Geomechanics and Geoengineering》2018,13(4):288-300
The use of granulated recycled rubber as a lightweight material in civil engineering applications has been widely growing over the past 20 years. Processed waste tires mixed with soils have been introduced as lightweight fills for slopes, retaining walls, and embankments. It has also been considered as a damping material under foundations in seismic zones. Understanding the properties of sand-rubber mixtures is essential to evaluate its performance in geotechnical applications. Isotopically consolidated drained (CD) triaxial tests were conducted to investigate the effect of rubber size, content and saturation condition on the mechanical properties of sand-rubber mixtures. Moreover, the compressibility of the sand-rubber mixtures under sustained loading was investigated through one dimensional consolidation tests. The unit weight, shear strength and stiffness of sand-rubber mixtures decreased whereas deformability increased at increased rubber content. A non-linear stress-strain response was observed, that changed from brittle to ductile behaviour at increased rubber content. Sand-rubber mixtures, under one dimensional loading, exhibited significant settlement that increased as rubber content increased. 相似文献
11.
Shear strength of municipal solid waste for stability analyses 总被引：2，自引：0，他引：2
This paper investigates the shear strength of municipal solid waste (MSW) using the back analysis of failed waste slopes as
well as field and laboratory test results. Shear strength of MSW is a function of many factors such as waste type, composition,
compaction, daily cover, moisture conditions, age, decomposition, overburden pressure, etc. These factors together with non-standardized
sampling methods, insufficient sample size to be representative of in situ conditions, and limited shear displacement or axial
strain imposed during the laboratory shear testing have created considerable scatter in reported results. Based on the data
presented herein, large shear displacements are required to mobilize the peak shear strength of MSW which can lead to displacement
incompatibility between MSW and the underlying material(s) such as geosynthetic interfaces and foundation soils. The data
presented herein are used to develop displacement compatible shear strength parameters for MSW. Recommendations are presented
for modeling the displacement and stress dependent strength envelope in stability analyses. 相似文献
12.
The stability of mine waste dump is very important for an economic and safety point of view. The biological method is the
most popular and eco-friendly approach to stabilize the mine waste dump in the long term. Trees outclass grasses and shrubs
for long term stability as the roots of trees are stronger and penetrate deeper. Their roots bind the dump material and form
a composite material having high shear strength. The mechanics of stabilization by tress have yet not been fully understood.
Moreover, one always refers to biological stabilization of slope qualitatively rather than quantitatively. A numerical simulation
tool has been used in the present paper to assess the increased factor of safety of a vegetated dump slope. The Sisam tree
was chosen for the present study as it is commonly available in northern India, needs little care and has high economic value.
The increased shear strength of the dump mass having tree roots was calculated by shear box test. The tree roots occupy large
space, hence, a large size shear box (1.5 m × 1.5 m × 0.75 m) has specifically been designed and fabricated for determining
the shear strength of dump root matrix. A small size shear box (0.30 m × 0.30 m × 0.15 m) has also been designed and fabricated
to determine the increased shear strength due to small trees. It was observed that the Sisam tree of even moderate size binds
the upper layers of mine dump and improve the factor of safety substantially. It was also observed that the stability of dump
slope improves with time (i.e. size of tree). 相似文献
13.
排土场散体岩石粒度分布与剪切强度的分形特征 总被引：16，自引：5，他引：11
应用分形理论研究了矿山排土场散体岩石粒度分布的分维规律,建立了分维数与排土场散体物料剪切强度参数的定量关系式。研究表明,排土场岩石块度分布具有良好的分形结构,分维数值大小随着排土场高度的增加而增加,但不超过3。当采样尺度范围一定时,分维数越大,散体中细颗粒含量越多,平均粒径也越小。分维数与散体岩石的剪切强度参数摩擦角?呈负指数关系。分维数值可用于排土场粒度资料的统计分析与剪切力学强度参数的预测。 相似文献
14.
The raw material soil of Al-Sowera factory quarry (quarry soil and mixture) used for building brick industry was tested mineralogically, geochemically and geotechnically. Mineral components of soil are characterized by Clay minerals (Palygoriskite and chlorite) and non-clay minerals like calcite, quratz, feldspar, gypsum and halite. The raw material is deficient in SiO2, Al2O3, K2O, Fe2O3 and MgO, while enriched in CaO. Loss on ignition and Na2O are in suitable level and appear to be concordant with the standard. Grain size analyses show that the decreasing sand and clay, and increasing silt ratio in both quarry soil and mixture caused decreasing in strength of brick during molding and after firing. The quarry soil is characterized by high plasticity clayey soil of 30.49 plastic index (P.I), whereas the mixture considered a clayey soil has a low plasticity of 7.7 plastic index (P.I). To improve the chemical and physical properties of the raw material, alumina-silicate minerals rich in K2O, Fe2O3 and MgO are recommended as additive materials to the main mixture. 相似文献
15.
In this paper, marble waste is evaluated as a secondary material to be utilized as potential stabilizer to improve the volume change and strength characteristics of sand-amended expansive soil, proposed as a possible landfill, pavement or sub-base material in a semi-arid climate. An experimental program was conducted on sand-expansive soil enhanced with marble waste, abundantly found as a by-product of construction industry, obtained from two different sources with different gradations, denoted as marble powder (MP) and marble dust (MD). One-dimensional swell, volumetric shrinkage, consolidation, unconfined compressive and flexural strength tests were conducted on expansive soil–sand mixtures with 5, 10 and 20% waste marble inclusions over curing periods of 7, 28 and 90 days. Test results showed that 10% marble powder and 5% marble dust by dry mass were the optimum amounts for mitigating the swell–shrink potential and compression index as well as yielding the highest unconfined compressive and flexural strength values. Moreover, the rate of reduction in swell potential versus the flexural strength over the curing periods studied is highest in 10% MP- and 5% MD-included specimens, the latter being more insensitive to this change. The soil mixtures displayed brittle behavior after marble addition, hence its utilization as a secondary additive to sand-amended expansive soil is recommended for soils exposed to lower flexural loads such as light traffic. 相似文献
16.
Triaxial testing is being carried out on a mixture of Na-bentonite and sand to provide parameters for computer modelling of a nuclear-fuel waste disposal vault when the material is used as a sealant. Drained and undrained tests with porewater pressure measurement have been performed at confining pressures up to 6 MPa. The program is now being extended to 10 MPa and elevated temperatures.
In the long term, at room temperatures, it is predicted that the material will behave like a normally consolidated clay and strain harden plastically with increasing mean effective stress. In shear, its undrained strength will decrease slightly after failure. Working relationships, based on critical state soil mechanics, have been established for the normal consolidation and failure conditions of the material. The behaviour of the material in drained conditions can be predicted from these relationships. 相似文献
17.
Ali Firat Cabalar 《Geotechnical and Geological Engineering》2011,29(4):411-418
Waste tires are used in some engineering applications and thereby reduce the potential impact on the environment, for example,
as lightweight materials in geotechnical engineering projects. This paper presents a brief literature review on geotechnical
applications of processed waste tires, and a laboratory study on the effect of tire shreds on the physical properties of two
different sands (fine angular sand and coarse rotund sand). Each type of sand was mixed four different percentages of rubber
particles; 5, 10, 20 and 50% by dry weight. Direct shear tests were employed to investigate the effect of rubber particles
on the shear strength of sands and internal friction angle. The addition of shredded waste rubber particles slightly decreased
both the internal angle of friction and the shear strengths of the sands within the tested stress and strain levels. Additionally,
a prediction model using stepwise regression (SR) method is proposed to calculate the shear strength of sands with the increasing
rubber content. The performance of accuracies of proposed SR models are quite satisfactory. The proposed SR models are presented
as relatively simple explicit mathematical functions for further use by researchers. 相似文献
18.
Investigation of solid waste soil as road construction material 总被引：1，自引：0，他引：1
The geotechnical properties of solid waste soils for use as sub-base materials in road construction were investigated. A series of field tests and laboratory tests were performed to assess the physical and mechanical properties of the solid waste soils sampled from a landfill site, near to a riverside, which had been reclaimed over the last two decades. The tests showed that geotechnical properties are clearly affected by the magnitude of organic matter content. As the organic matter content increases, the maximum dry unit weight, the shear strength and bearing capacity of ground decrease, while the void ratio and compressibility increase. If the organic matter content is more than about 8% in solid waste soils, it is not suitable for use as a sub-base material in road construction due to the significant decrease of shear strength and bearing capacity. 相似文献
19.
The use of shredded waste tires to improve the geotechnical engineering properties of sands 总被引：2，自引：0，他引：2
Mousa F. Attom 《Environmental Geology》2006,49(4):497-503
A new geo-environmental approach was proposed to use waste tires in certain engineering applications and thereby reduce the
potential impact on the environment. This paper presents a laboratory study on the effect of shredded tires on the physical
properties of some sands. Shredded tires were passed through US sieve size 4 and mixed with three different types of sands
with varying gradations. Each type of sand was mixed with four different percentages of shredded tires: 10, 20, 30 and 40%
by dry weight. Direct shear tests were conducted to study the effect of the shredded tires on the shear strength properties
of sands, such as angle of internal friction and shear strength. The addition of shredded waste tires increased both the angle
of internal friction and the shear strength of the sands. Additionally, a prediction model was developed to calculate the
shear strength of sand due to increasing shredded tire content. The shredded tires improved some engineering properties of
sand. 相似文献
20.
城市固体废弃物的剪切强度机理及本构关系 总被引：2，自引：0，他引：2
根据城市固体废弃物（简称MSW）的大三轴固结排水剪试验结果,延伸岩土工程中研究土体的概念和方法,研究MSW的剪切强度机制。MSW与大变形相关的强度特性主要是由于含有大量的纤维状成分所致,在剪切过程中试样总的抗剪能力由剪切面上的摩擦力和纤维状加筋相的拉力所产生。MSW的摩擦强度主要由3部分构成：纤维状成分与土颗粒之间的摩擦,纤维状成分之间的摩擦,和土颗粒之间的摩擦。基于MSW的剪切强度特性,采用邓肯-张本构模型来描述MSW的应力-应变关系。 相似文献