On the Use of Random Material in Dam Cores: Case of the Manso Dam, Brazil

Ferreira, Breno S.; Almeida, M. S. S.; Cavalcanti, Maria do Carmo Reis; Filho, Celso José Pires

doi:10.1007/s10706-021-02003-7

“…SF der , SF ing , and SF inh were soil heavy metal carcinogenic tilt factors [mg (kg day) -1 ] under skin contact, handoral ingestion, and oral-nasal respiratory exposure, respectively. See Table 2 [15,16]. If CR < 10 −6 , there was no carcinogenic health risk.…”

Section: Methodsmentioning

confidence: 99%

A Monitoring System for Air Quality and Soil Environment in Mining Areas Based on the Internet of Things

Dai

¹

,

Huang

²

,

Mao

³

2022

View full text Add to dashboard Cite

In order to solve the intensifying problem of heavy metal pollution of soil in mining areas, a method for monitoring air quality and soil environment in mining areas based on the Internet of Things is proposed. Using meta-analysis method and health risk assessment method, the impact of mining on soil heavy metal content in Southwest China was quantitatively analyzed, and the relationship between soil heavy metal value and its potential influencing factors was discussed, as well as the heavy metal pollution, ecological risk, and health caused by soil mining activities. Risks were assessed. The results showed that artificial and oral intake were the main modes of soil heavy metal exposure, with the highest daily intakes for noncarcinogenic risk children and the highest daily intakes for carcinogenic risk adult females. The noncarcinogenic risk (HQ>1) of soil As and Pb exposure to children was 3.74 and 1.44, respectively. The carcinogenic risk values of As, Cd, Cr, and Ni in soil were all higher than 10-6, indicating that the carcinogenic risk was within the tolerance range of human body. Children were exposed to the combined noncarcinogenic risk ( HI = 3.83 ), and the risk values of the three types of recipients were 1.19 × 10 − 4 , 1.21 × 10 − 4 , and 1.06 × 10 − 4 , respectively. The correlation between heavy metal content and environmental factors was obtained. It is verified that the system in this paper can effectively monitor the meteorological environment and soil environment, and at the same time, it reveals the pollution law of heavy metals in the soil of the mining area, which provides supporting conditions for future mining and heavy metal pollution management.

show abstract

“…Experiences from constructing earth core rockfill dams using widely graded materials in China were reported by Xu and Jiang [6]. Ferreira et al [7] reported the application of residual and colluvial soils for constructing core section of Manso Dam, Brazil. Additionally, Hongqi and Fudong [8] presented outstanding experience in blending coarse gravel (50 -65%) and fine cohesive soils (< 35%) for constructing core in Changheba Dam, China.…”

Section: Random Fill Materialsmentioning

confidence: 99%

Case History of Random Material Shear Strength Evaluation using In-situ Large Scale Direct Shear Test in the Construction of the Longest Dam in the Southeast Asian

Sahadewa

2023

IOP Conf. Ser.: Earth Environ. Sci.

1

0

View full text Add to dashboard Cite

A modern dam offers many benefits to society, including water conservation, farming sustainability, energy source, and recreational activities. In Indonesia, more than 50 dams are constructed as strategic national projects within the last decade. A zoned earth-fill dam, built using soil and rock materials, is one of the most common dam types in Indonesia. This dam allows a specific material type to be placed in a particular zone, including random material fill zone. A random material is usually obtained from dam excavation work as well as borrow area. It normally contains wide range of grain sizes and a variety of weathering degree. On one hand, this material is very economic. On the other hand, it introduces a challenge in shear strength assessment. Random material frequently contains large size grain that inhibits regular laboratory test use. A catastrophic Indonesian dam construction failure in 2021 was partly attributed to inadequacy in assessing shear strength of random material. This case history highlighted the importance of a proper random material shear strength evaluation. The other dams coincidentally under construction at that time then experienced rigorous shear strength evaluations, including Semantok Dam in Nganjuk, East Java. This dam, designed to be approximately 33-m max high and 3.1-km long, is the current longest dam in the Southeast Asian. An in-situ large scale direct shear device as large as 80 cm × 80 cm × 30 cm was developed to test random material in Semantok Dam. Eight locations in random fill zones were selected. Three series of direct shear test were conducted in each location. Testing results based on 24-large size sample showed a great variability in Mohr-Coulomb parameters. The angle of internal friction ranged from 11.4° to 36.7° with average value of 27.8°, whereas the cohesion varied from 25.3 kPa to 138.6 kPa with average value of 85.2 kPa. High variation in shear strength parameters showed that such test should be performed to verify the design parameter. This in-situ large scale direct shear test provides an appealing method to assess shear strength of random material. This large-scale test is strongly recommended for a common practice in dam construction.

show abstract

“…Xu and Jiang [8] presented experiences from building earth core rockfill dams using broadly graded materials in China. Ferreira et al [9] described the use of colluvial and residual soils for building core in Manso Dam, Brazil. In addition, Hongqi and Fudong [10] described outstanding experience in blending coarse gravel (50% -65%) and fine cohesive soils (< 35%) for building core in Changheba Dam, China.…”

Section: Random Materialsmentioning

confidence: 99%

<i>In Situ</i> Large Scale Direct Shear Test for Evaluating Compaction Work of Random Material: Case of Construction Failure in an Indonesia Dam

Sahadewa

2023

KEM

1

0

View full text Add to dashboard Cite

Random material is commonly used for building dam embankments. On one hand, random fill materials offer many advantages, such as saving construction cost and reducing environmental impact. On the other hand, the shear strength of random materials is exceedingly difficult to assess. This difficulty is mainly associated with large size particles in random materials that inhibit the use of regular testing equipment. In fact, misinterpretation of random material shear strength can lead to a catastrophic dam failure. An in-situ large scale direct shear device as large as 70 cm x 70 cm x 30 cm was developed for random material testing. This device has been utilized successfully to investigate construction failure of a dam in Indonesia. Post failure testing at some locations in this dam showed low shear strength and loose material behavior, which may be associated with the collapse. This large in-situ test offers an attractive method for evaluating the effect of compaction work on random material, such as shear strength, shear-strain behavior, and density. Decision, whether the current design and compaction work should be re-evaluated or continued, can be made. This test is strongly advised as regular practice in dam construction.

show abstract

On the Use of Random Material in Dam Cores: Case of the Manso Dam, Brazil

Cited by 5 publications

References 14 publications

A Monitoring System for Air Quality and Soil Environment in Mining Areas Based on the Internet of Things

A Monitoring System for Air Quality and Soil Environment in Mining Areas Based on the Internet of Things

Case History of Random Material Shear Strength Evaluation using In-situ Large Scale Direct Shear Test in the Construction of the Longest Dam in the Southeast Asian

<i>In Situ</i> Large Scale Direct Shear Test for Evaluating Compaction Work of Random Material: Case of Construction Failure in an Indonesia Dam

Contact Info

Product

Resources

About