scholarly journals Analysis of soil conditions and pipe behaviour at a field site

2011 ◽  
Vol 48 (6) ◽  
pp. 847-866 ◽  
Author(s):  
Yafei Hu ◽  
Hung Q. Vu
Keyword(s):  
Expansive Soils ◽  
Soil Conditions ◽  
Soil Pressure ◽  
Field Instrumentation ◽  
Differential Movement ◽  
Water Mains ◽  
Important Means ◽  
Water Main ◽  
Pipe Breakage ◽  
Soil Behaviour

Water main pipes buried in expansive soils are often subjected to severe distress subsequent to installation. Excessive stresses may be induced due to either differential movement of the soils or swelling pressures from the soils along the pipes, impairing their performance or even breaking them. Field monitoring is an important means for understanding soil behaviour and its interaction with water mains. For this purpose, field instrumentation was successfully installed to monitor the performance of a section of water main placed in a well-developed area of a city neighbourhood where more frequent pipe breakage had occurred in recent years. The instrumentation included sensors to measure pipe wall strains, pipe displacement, in situ soil water content, soil pressure, and temperature. The instruments were installed in both the soil backfill and native soil around the backfill. This paper presents the analyses of monitoring data collected during the first 3 years after instrument installation. It was observed that the soil and pipe behaviour was affected significantly by soil properties and seasonal changes and correlated closely with the change pattern of the local meteorological conditions.

Field performance of in-service cast iron water reticulation pipe buried in reactive clay

2015 ◽  
Vol 52 (11) ◽  
pp. 1861-1873 ◽  
Author(s):  
Derek Chan ◽  
Chaminda Pathma Kumara Gallage ◽  
Pathmanathan Rajeev ◽  
Jayantha Kodikara
Keyword(s):  
Cast Iron ◽  
Moisture Content ◽  
Water Pressure ◽  
Field Performance ◽  
Soil Conditions ◽  
Soil Pressure ◽  
Buried Structures ◽  
Pipe Water ◽  
Important Means ◽  
Pipe Breakage

Field monitoring is an important means for understanding soil behaviour and its interaction with buried structures such as pipeline. This paper details the successful instrumentation of a section of an in-service cast iron water main buried in an area of reactive clay where frequent water pipe breakage has been observed. The instrumentation included measurement of pipe strain; pipe water pressure and temperature; soil pressure, temperature, moisture content, and matric suction; as well as the meteorological conditions on site. The data generally indicated that changes in soil temperature, suction, and moisture content were directly related to the local climatic variations. The suction and moisture content data indicated that the soil profile at the site down to around 700 mm, and probably down to 1000 mm, is affected by changes in surface weather, while soil conditions below this depth appear to be more stable. Analysis of pipe strain indicated that the pipe behaves like a cantilever beam, with the top experiencing predominantly tensile strains during summer. Subsequently, these trends reduce to compressive strains as soil swelling occurs because of the increase of moisture content with the onset of winter.

scholarly journals Pipe–soil interaction analysis of jointed water mains

1996 ◽  
Vol 33 (3) ◽  
pp. 393-404 ◽  
Author(s):  
B Rajani ◽  
C Zhan ◽  
S Kuraoka
Keyword(s):  
Ductile Iron ◽  
Interaction Analysis ◽  
Water Pressure ◽  
Urban Infrastructure ◽  
Developed Countries ◽  
Temperature Influence ◽  
Average Life ◽  
Winkler Model ◽  
Water Mains ◽  
Water Main

Water mains are important lifelines of modern urban infrastructure. However, in most developed countries, the average life of these cast or ductile iron pipes approaches 50–75 years. In recent years, the disruption of water sevices as a consequence of water main breaks is on the rise in most Cadadian cities. This paper describes the developement of a simplified Winkler model to stimulate the responses of a jointed water main subjected to differential temperature change and water pressure. The simplified Winkler model accounts for axial and radial restraints offered by the surronding soil. In spite of its simplicity, the Winkler model is able to predict the overall response of strains and stresses, which confirms satisfactorily some of heuristic and documented observations on water main breaks. Key words: water main breaks, pipe–soil interaction, temperature influence, Winkler model.

Effect of Bridge-Soil Interaction on Behavior of Integral Bridge

2011 ◽  
Vol 137 ◽  
pp. 123-127
Author(s):  
Tian Lai Yu ◽  
Mohammed Awad
Keyword(s):  
Finite Element ◽  
Element Model ◽  
Soil Condition ◽  
Soil Conditions ◽  
Integral Abutment ◽  
Soil Pressure ◽  
Element Analysis ◽  
Dense Sand ◽  
Integral Bridge ◽  
Axial Forces

In this paper analytical evaluation of influence of bridge-soil interaction on the structural behavior of integral bridge with adjacent concrete box beams deck subjected to temperature rise was performed. Three different soil conditions loose, medium, and dense sand for the uppermost layer soil adjacent to abutment and abutment column were studied. Long-term, field monitoring was performed on FuYu bridge located in Heilongjiang province, China. The recorded data was used to validate the accuracy of a finite element model of this bridge which explicitly incorporates the nonlinear soil spring response. The finite element analysis indicated that soil condition adjacent to the abutment and abutment column is important factor affecting the response of the integral abutment bridge to thermal loads in terms of soil pressure behind the abutment, and axial forces and moments in the composite deck. As the soil varied from loose to dense condition the soil pressure behind the abutment increases more than 4 times and axial forces in the bridge deck increases by about 50% and bending moments in the composite deck increases by about 40%.

scholarly journals Water Main Failure Risk Assesment / OCENA RYZYKA AWARII MAGISTRALI WODOCIĄGOWEJ

2012 ◽  
Vol 24 (1) ◽  
pp. 115-124
Author(s):  
Andrzej Studziński ◽  
Katarzyna Pietrucha-Urbanik
Keyword(s):  
Water Demand ◽  
Water Storage ◽  
Negative Consequences ◽  
Storage Tanks ◽  
Water Network ◽  
Pipe Failure ◽  
Water Mains ◽  
Water Main ◽  
Qualitative Risk Analysis ◽  
Made In

Abstract Town of Krosno is supplied with water by 3 intakes: Sieniawa, Iskrzynia and Szczepańcowa. After the treatment water flows in water mains to the water network in Krosno. The aim of his paper is qualitative risk analysis of the water main Sieniawa failures. The consequences of the failure: pressure value in the network and its duration, were described for different conditions of failures: time of failure, water demand and water storage tanks initial filling. For simulations of pipe failure water network model made in Epanet 2 program was used. The model was verified both during operation of water network and during the failure, where field data were used. The results of the simulations are corresponding to observations made during the real failures. Negative consequences appear only after emptying the water storage tanks, it results from two features of the storage tanks: they stabilize pressure in the network and for some time can provide water to the network. The time of emptying the storage tanks varies according to water demand their initial filling, it is at least 3 hours. During this time the are no sign of failure. When the storage tanks are empty reduction of pressure an shortage of water are observed on prevailing area of Krosno.

Effectiveness of Chemical Grouting and Stone Blowing as Remedial Measures to Mitigate Differential Movement at Railroad Track Transitions

2016 ◽  
Author(s):  
Debakanta Mishra ◽  
Huseyin Boler ◽  
Erol Tutumluer ◽  
James P. Hyslip
Keyword(s):  
Fine Particles ◽  
Remedial Measures ◽  
Chemical Grouting ◽  
Track Geometry ◽  
Damping Characteristics ◽  
Field Instrumentation ◽  
Track System ◽  
Differential Movement ◽  
Foundation Type ◽  
The University

Railway transitions like bridge approaches experience differential movements related to differences in track system stiffness, track damping characteristics, foundation type, ballast settlement from fouling and/or degradation, as well as fill and subgrade settlement. A recent research study at the University of Illinois has used advanced geotechnical instrumentation to identify and quantify different factors contributing to recurrent differential movement problems at three different bridge approaches along Amtrak’s Northeast Corridor (NEC) near Chester, Pennsylvania. Field instrumentation data have indicated excessive ballast movement to be the primary factor contributing to the “bump” development at these bridge approaches. Among the different remedial measures applied to mitigate the recurrent track geometry issues were: (1) Chemical Grouting, (2) Stone Blowing, and (3) Under-Tie Pads. This paper will discuss the implementation methods using track geometry records and instrumentation data, and highlight the effectiveness of chemical grouting and stone blowing to mitigate the differential movement problem at railroad bridge approaches. According to the trends in the transient ballast deformation data collected under train loading, both remedial measures were effective in significantly reducing excessive ballast deformation, which was the primary mechanism behind the bump development at these locations. Ballast degradation and presence of excessive fine particles in the ballast layer adversely affected the ability of the grout to bond with aggregate particles. A “clean” ballast layer, on the other hand, facilitated adequate bonding between the grout and ballast particles leading to significantly improved long-term track performance.

scholarly journals Development of Some Novel Suction-Based Correlations for Swell Behavior of Expansive Soils

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Bakht Zamin ◽  
Hassan Nasir ◽  
Khalid Mehmood ◽  
Qaiser Iqbal ◽  
M. Tariq Bashir ◽  
...  
Keyword(s):  
Pore Water Pressure ◽  
Expansive Soils ◽  
Water Pressure ◽  
Expansive Soil ◽  
Field Testing ◽  
Published Data ◽  
The Novel ◽  
Field Instrumentation ◽  
Swell Potential ◽  
Unsaturated Expansive Soils

Swelling and shrinkage are the two distinctive characteristics of expansive soils, and due to this behavior, these soils are considered a natural hazard for infrastructure. Many structures in different regions have been impaired due to the swell/shrink behavior of the expansive soil. Most of the severe distress is impeded because of the inherent suction (negative pore water pressure) present in expansive soils. Both suction and swelling parameters are greatly affected by the surrounding moisture content. Due to this feature of expansive soil, geotechnical engineers are interested in utilizing the suction-based correlations for the assessment of unsaturated expansive soils. The current investigation was carried out to develop novel correlations incorporating lab testing and field instrumentation. To fulfill the objectives, eight sites of the local expansive soil in Pakistan were selected for samples collection and field testing. Conventional odometer testing was conducted to measure the swell pressure (Sp) and swell potential (S) of the fabricated/remolded specimens. Gypsum block (G-block) sensors were additionally utilized for estimating the matric suction in the field. To expand the database, the previously published data of the same nature was also incorporated. Based on the results, the power form of the novel correlations (suction-based) is highly significant for estimating (Sp), while for swell potential, the logarithmic correlation with R2 = 0.6551 is more significant than other forms of correlations. The proposed suction-based correlation can be equally utilized for the estimation of field suction as well as for swell behavior of expansive soil having a plasticity index (PI) ≥ 22%.

scholarly journals Current water main rehabilitation practice using trenchless technology

2021 ◽  
Author(s):  
Yichen Wu ◽  
Chao Kang ◽  
Mohammad Molavi Nojumi ◽  
Alireza Bayat ◽  
George Bontus
Keyword(s):  
Trenchless Technology ◽  
Structural Support ◽  
Rehabilitation Technology ◽  
Underground Utilities ◽  
Water Mains ◽  
History Of ◽  
Current Water ◽  
Water Main ◽  
Infrastructure Rehabilitation ◽  
And Control

Abstract The market for water infrastructure rehabilitation is growing rapidly due to the increasing age of underground utilities. Currently, two common water main rehabilitation methods exist: cured-in-place pipe (CIPP) and polymer spray-on coatings. CIPP can provide structural support for both internal and external loads, while spray-on techniques provide chemical resistance as well as adding minor strength to the existing pipe. This paper summarizes water main rehabilitation practice using CIPP and spray-on methods. The history of trenchless rehabilitation technology is discussed, as well as current methodologies and products for water mains. The design, installation, and monitoring of water main rehabilitation products are also summarized, along with the associated risks. Quality assurance and control (QA/QC) methods are included for evaluating existing products and procedures.

scholarly journals Effect of Polymeric Resins on Geotechnical Properties of Black Cotton Soil

2020 ◽  
Vol 8 (5) ◽  
pp. 1781-1785
Keyword(s):  
Expansive Soils ◽  
Expansive Soil ◽  
Geotechnical Properties ◽  
Black Cotton Soil ◽  
Soil Conditions ◽  
Chemical Stabilization ◽  
Stabilization Method ◽  
Mechanical Stabilization ◽  
Polymeric Resins ◽  
Moisture Barriers

Stabilization of black cotton soil is a challenging task for geotechnical engineers since such soil is highly vulnerable to expansive characteristics when the moisture content is increased. Due to its expansive nature, it is also called as swelling or expansive soils. Among the clay minerals, Montmorillonite is mainly responsible for such expansive characteristics. Bore log profile has a cluster of soil specimens including black cotton soil also which is unavoidable. Soil engineers have a serious concern about such expansive soil since it is treacherous for foundation of buildings. To overcome such deficiencies it becomes essential to stabilize the soil conditions. The commonly employed methods to decrease the expansive behaviour are: Chemical stabilization, Mechanical stabilization and installation of moisture barriers. In this paper, chemical stabilization method is adopted. Soil stabilizers, namely, sodium silicate, epoxy resin and polyvinyl alcohol are chosen and are mixed with black cotton soil in varying proportions of 5%, 10% and 15% to study the changes in geotechnical properties. From the results it is evident that polymer treated soils reduce plasticity characteristics and shows better results in geotechnical properties.

scholarly journals An Experimental Study on the Effect of Micro-Metakaolin on the Strength and Swelling Characteristics of Expansive Soils

2022 ◽  
Author(s):  
Mohamed Sakr ◽  
Waseim Azzam ◽  
Mohamed Meguid ◽  
Hebatalla Ghoneim
Keyword(s):  
Expansive Soils ◽  
Expansive Soil ◽  
Swelling Pressure ◽  
Soil Conditions ◽  
Arid Areas ◽  
Continuous Increase ◽  
Swell Index ◽  
The World ◽  
Swelling Characteristics ◽  
The Government

Abstract Expansive soils are found in many parts of the world, especially in arid areas and dry weather regions. Urbanization and development of new cities around the world resulted in construction in areas of challenging subsurface soil conditions. For example, in the Middle East, the Government of Egypt is building several new cities to accommodate the continuous increase in the country’s population. Most of these new cities are located in areas underlain by expansive soils. In this study, a series of laboratory tests were carried out to investigate the effect of introducing micro-metakaolin into the matrix of an expansive soil to improve the swelling potential as a new stabilizing material. Test results showed that micro-metakaolin can considerably decrease the free swell index of the soil by 37% and 54% at micro-metakaolin content of 15% and 25%, respectively. In addition, the shear strength of the soil was found to also increase as a result of the introduction of the micro-metakaolin material. Adding 25% micro-metakaolin content reduced the swelling pressure of the soil by about 33%. The results suggest that the proposed method is efficient in stabilizing and improving the properties of expansive soils found in arid areas. This is important to control excessive swelling and prevent possible damage to the supported structures.

Water Hammer Causes Water Main Breaks

2019 ◽  
Vol 142 (2) ◽  
Author(s):  
Robert A. Leishear
Keyword(s):  
Galvanic Corrosion ◽  
Fatigue Cracks ◽  
Water System ◽  
Underground Water ◽  
Water Hammer ◽  
Surface Corrosion ◽  
Water Mains ◽  
Water Main ◽  
Number Of Cycles ◽  
Hoop Stresses

Abstract Most underground water main breaks can be stopped, since the technology is now available to evaluate water system piping failures and determine corrective actions. The problem is defined in terms of several variables: (1) Water hammer is the initiator of nearly all underground water main breaks. (2) In nonacidic soils, fatigue directly causes piping cracks. (3) In acidic soils, water hammer cracks the pipes, and crevice corrosion is accelerated at those crack sites. Additionally, those cracks serve as moisture sources to induce piping surface corrosion due to galvanic corrosion between the soil and the metallic pipe wall. Even so, some failures are solely due to corrosion. (4) Dynamic pipe stresses are significantly larger than stresses caused by static loading, i.e., hoop stresses and strains may be as much as four times the calculated static stress due to water hammer. (5) If dynamic stresses are not considered, calculations incorrectly conclude that water mains will not be damaged. (6) That is, water hammer calculations determine pressure surge magnitudes that are multiples of the operating pressures, where dynamic effects cause fatigue cracks due to the applied pressures and the number of cycles for those pressures to break water mains.

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