Test Research on Influence of Water and Mineral Composition on Physical and Mechanical Properties of Phyllite

Li, Xin Zhe; Wang, Geng Feng; Cao, Lihua

doi:10.4028/www.scientific.net/amm.496-500.2398

Cited by 6 publications

(5 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The increase in PSD observed may be caused by the dissolution/precipitation reactions, which can weaken the grain-grain bonding and result in detachment. However, results from other reported researches showed that rock strength can be linked with the composition of its minerals (Li et al 2014;Pan et al 2016;Sun et al 2017;Zhang et al 2018), grain shape and size (Sun et al 2017;Jin et al 2017), and its particle size distribution (Hussain et al 2006;Shimizu et al 2010 ). According to Jin et al (2017 ), the shapes of rock materials and grain size contribute to the strength of its cemented soil-rock mixtures.…”

Section: Effect Of Chemical-rock Interaction On Particle Size Distrib...mentioning

confidence: 99%

Oilfield chemical-formation interaction and the effects on petrophysical properties: a review

2022

View full text Add to dashboard Cite

Oil and gas recovery may cause formation damage during drilling, completion, and production phases. As a result of fundamental chemical, thermal, mechanical, and biological interactions, formation damage can occur due to impairment of permeability and porosity, causing undesirable operational and economic problem. The fluid-rock interactions resulting from oilfield chemicals injection during drilling, enhanced oil recovery (EOR) such as chemical flooding, or formation treatment could negatively impact on the formation properties such as geomechanical and geochemical, leading to alteration of the rock’s petrophysical properties. These chemical-rock interactions induce changes in both pore space geometry and rock strength. The resultant impact includes weakening of the formation bonding materials, formation damage, reduced production and consequently sand production simultaneously with reservoir fluids. It is therefore critical to evaluate these variables prior to designing any geo-sequestration, reservoir stimulation or EOR projects. Studies have shown that rock properties, especially permeability, porosity and strength, are altered or damaged during drilling, cementing, perforating, producing, stimulating, and injecting water or chemicals for EOR. Petroleum companies are likely to suffer significant financial losses due to this. This study provides a review on the influence of oilfield chemical-formation interactions on the formation rock properties both geophysical and mechanical, leading to formation damage and sand production. This study aims to provide researchers with a single document that gives insight and new perspectives on oilfield chemical-rock interactions through compilation of recent studies relating to the effect of chemical-rock interactions on rock's petrophysical properties, as well as geomechanical properties due to geochemical reactions that cause formation damage and eventually sand production. Having a solid understanding of fluid-rock interactions and how they impact petrophysical properties and cause formation damage is essential in predicting sand production and would help in minimizing economic losses, downtime and technicalities.

show abstract

Section: Effect Of Chemical-rock Interaction On Particle Size Distrib...mentioning

confidence: 99%

Oilfield chemical-formation interaction and the effects on petrophysical properties: a review

2022

View full text Add to dashboard Cite

show abstract

“…The CWP soil is the product of complete weathering of phyllite and has a high level of expansibility when soaking [1−3]. Moisture content and mineral components have significant effects on physical and mechanical properties of phyllite [4,5]. X-ray fluorescence (XRF), X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) are often used to detect the mineral components or micro-structure of phyllite [6].…”

Section: Introductionmentioning

confidence: 99%

Study of Mutual Improvement of Completed Weathered Phyllite and Red Clay Based on Neutralization Effects of Swelling and Shrinkage Deformation

Zhao¹,

Yang²,

Rao³

et al. 2022

Journal of Renewable Materials

View full text Add to dashboard Cite

Completely weathered phyllite (CWP) soil is a kind of special soil with high swell potential, while red clay is a special soil with high shrinkage. This means that these two kinds of special soils are usually not suitable for direct use as subgrade fill. To reduce the swell index of the CWP soil and the shrinkage of red clay at the same time, it was proposed to blend the CWP soil with red clay to improve their basic characteristics. A series of swell index tests and dry-wet cycle tests of the blended soils have been carried out at varying blending ratios, compaction coefficients and moisture contents. The test results show that the free swell index of the blended soil decreases with the increase of red clay, moisture content and compaction coefficient, respectively. The fissure density of the blended soil first decreases and then increases with the blending ratio, with the lowest being zero when the blending ratio is ranging from 20% to 40%. Through particle microscopic analysis and elemental composition analysis, it is found that the neutralization effect, the dilution effect of swell minerals, and the partition effect of coarse particles play an important role in restraining expansion and shrinkage deformation of the blended soil. Based on the liquid limit requirement of Chinese Railway Design Code (TB 10001-2016), the optimal blending ratio of red clay has been proposed to be 50%. Compared with the CWP soil, the free load swell index of the blended soil is reduced by 45.0% and the fissure density is reduced by 99.3% compared with that of red clay. Therefore, it is feasible to improve the CWP soil by blending it with red clay at an optimal ratio of 50% by using the neutralization effect of the expansion of CWP and shrinkage of red clay.

show abstract

“…Weathered phyllite has the characteristics of high liquid limit [1][2], difficulty in compaction [3], and large deformation of subgrade filling when it is socked after compaction [4][5][6]. Many scholars have systematically analyzed the factors affecting the basic physical properties of weathered phyllite from microstructure and mineral composition perspectives [7][8][9].…”

Section: Introductionmentioning

confidence: 99%

“…The traditional methods of improving weathered phyllite with cement or lime mainly consider the longterm strength and long-term stability of subgrade fill, but a significant amount of cement or lime is required to achieve this [9,10]; Using red clay to improve CWP soil mainly considered the immediate strength [27], and the method can not only reduce the expansibility of CWP, but also reduce the fissures in red clay [29]. However, this type of improvement method is only suitable for ordinary railway subgrade applications but cannot satisfy the subgrade requirements for the high-speed railway.…”

Section: Introductionmentioning

confidence: 99%

Experimental Study on Improvement Effects of Completely Weathered Phyllite Using Red Clay and Cement for High-Speed Railway Embankments

Zhao¹,

Rao²,

Yang³

et al. 2022

Journal of Renewable Materials

View full text Add to dashboard Cite

Completely weathered phyllite (CWP) has the characteristics of difficult compaction, low shear strength after compaction and large settlement after construction. The traditional improvement method using a single agent of red clay or cement for CWP satisfies the subgrade requirements for ordinary railway, but cannot meet the requirements of immediate strength and long-term post-construction settlement of high-speed railway at the same time. A series of experimental investigations were undertaken for the blended CWP soils, with three additives used. The first additive was red clay, the second was cement and the third was a combination of both red clay and cement at various portions. Results of consolidation test and shear strength test carried out for the treated CWP soils show that: 1) The effect of cement on improving the compression modulus of CWP is much better than that of red clay; 2) The settlement of an embankment of 10 m high formed by blended soil of CWP with 3% cement can be controlled within 15 mm, while the settlement will be 25.15 mm for the same embankment of blended soil of CWP with 40% red clay; 3) The shear strength and ultimate bearing capacity of CWP improved by red clay are much better than those of 5% cement; 4) The ultimate bearing capacity of CWP improved by 40% red clay is 3.42 times of that by 3% cement and 2.95 times by 5% cement. Furthermore, the bearing capacity of CWP when improved by red clay can meet railway subgrade requirements immediately after compaction, while cement improved CWP needs a curing time of 1 day or longer. This is an impediment to rapid construction process. The improvement mechanism of red clay is mainly filling effect and grading improvement effect, while the improvement mechanism of cement is mainly hardening reaction, which produces high strength material to cement. It is found that 40% red clay and 3% cement treated CWP, which is considered to be optimum, can meet the subgrade requirements of both immediate bearing capacity and long-term post-construction settlement for the high-speed railway.

show abstract

Test Research on Influence of Water and Mineral Composition on Physical and Mechanical Properties of Phyllite

Cited by 6 publications

References 0 publications

Oilfield chemical-formation interaction and the effects on petrophysical properties: a review

Oilfield chemical-formation interaction and the effects on petrophysical properties: a review

Study of Mutual Improvement of Completed Weathered Phyllite and Red Clay Based on Neutralization Effects of Swelling and Shrinkage Deformation

Experimental Study on Improvement Effects of Completely Weathered Phyllite Using Red Clay and Cement for High-Speed Railway Embankments

Contact Info

Product

Resources

About