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Books by Arvind Jha

Ministry of Local Development DDC/DTO, Dhanusha Quality Ass urance Plan for Bridge Construction F... more Ministry of Local Development DDC/DTO, Dhanusha Quality Ass urance Plan for Bridge Construction Foreword to the Bridges Quality Assurance Plan The Quality Assurance Plan maps out what, when and how things will be done. It is a blueprint for a successful job. The current Bachharaja river bridge construction programme, apart from donor supported one, includes a large number of structures, among which a significant proportion are 25m span. These are major structures by any standard, and involve a huge financial investment by GoN, RAIDP, Nepal. The works are being constructed by national contractors, often with limited resources, and are supervised by DDC/DTO/RAIDP staff working under difficult conditions in remote locations. The Bridges QA Plan has been prepared in response to the declared needs of the field staff involved in bridge construction. It covers the major issues raised by those staff, recognizing the l im it ed r es ou r c es available. The doc um ent is i nt en d ed to b ri ng ab out inc rem ent al changes in the management of bridge construction by Contractors, with the longer term objective of improving overall quality of construction. The scope of the QA Plan will be expanded in future revisions as field divisions become familiar with the requirements and implementation of the QA processes.

Papers by Arvind Jha

The use of lime and fly ash to improve the properties of certain types of soil is well establishe... more The use of lime and fly ash to improve the properties of certain types of soil is well established. However, the potential of fly ash to control the adverse effects of lime-treated gypseous/sulphatic soil has not been well investigated. In the present work, an attempt is made to quantify the fly ash content used to suppress the susceptible behavior of lime-treated gypseous soil. Series of one-dimensional swell and compressibility analyses are performed on various combinations of expansive soil with a predominance of montmorillonite mineral containing lime, gypsum (0–6%), and fly ash (0–30%). It is observed that the volume change behavior of the lime-treated gypseous soil is not controlled completely by addition of fly ash. However, the maximum improvement in the volume change behavior of the lime-treated gypseous soil is observed with a 20% fly ash content, and hence, can be taken as the Optimum Fly ash Content (OFC). Micro-analyses revealed that the relative dominance of the change in gradation and the formation of cementitious compounds of different compositions and ettringite crystals are the key factors in controlling the volume change behavior of lime-treated gypseous soil with fly ash. However, several factors, such as the types of minerals present in the soil, the types of fly ash and lime, and other physico-chemical environmental conditions (temperature, method of curing, and so on), are seen in the present study to affect the value of the obtained OFC.

Geo-climatic environmental conditions lead to the formation of gypsum-rich soils which occur in d... more Geo-climatic environmental conditions lead to the formation of gypsum-rich soils which occur in dry condition throughout world where the annual quantity of rain water is insufficient for leaching the gypsum from these soils. Soils containing gypsum, also known as gypseous/gypsiferous soil, are not preferred as a construction material; however, the scarcity of land and an increase in the utilization of soils for construction purpose have drawn an attention of research community to address the associated problems for its effective uses. The present article reviews the physico-chemical behaviour of gypsum, sources of gypsum in the soils, and also reveals the misconceptions on the suitable terminology used for soil containing gypsum. Further, the various methods proposed to identify the gypsum containing soil are discussed. The problems due to the phase transformation and its solubility characteristics of gypsum on the different construction activities are also reviewed in brief. The purpose of present article is to acquaint the impact of gypsum in the properties of different soils and to bring out the different methods available for stabilizing the gypsum containing soil. The refinements herein proposed aim to help understand the various aspects of gypseous soil and to institute the further research to be done in this topic.

An attempt has been made to examine the role of fly ash content (0–30%) to control undesirable st... more An attempt has been made to examine the role of fly ash content (0–30%) to control undesirable strength loss in lime–treated expansive soil containing gypsum (0–6%) after curing for different periods up to one year. Further, detailed experimental investigations have been performed to assess the plasticity, swell index and compaction behavior of soil treated with these additives. Results of the strength behavior revealed that a significant effect of higher fly ash content in the strength development of lime–treated soil is observed after longer curing periods. Presence of increasing amounts of gypsum accelerates early strength gain initially, but reduces long–term strength gain in soil–lime–fly ash mixes. Fly ash improves the strength of lime–treated gypseous soil. However, beneficial use of fly ash to improve the strength of lime treated gypseous soil depends on the amount of gypsum present in the soil and length of curing periods. Micro–analyses (XRD and SEM) revealed that the strength development is controlled by reaction products formed such as cementitious compounds and ettringite crystals.

The interaction of ions (calcium, alumina, silica, and sulfate) in the presence of water is very ... more The interaction of ions (calcium, alumina, silica, and sulfate) in the presence of water is very complex to indentify, and hence, to predict the behaviour of soil. An attempt has been made to understand the mineralogical and micro–structural changes due to soil–lime–gypsum reactions. Further, the associated mechanisms behind changes in the properties of lime treated gypseous soil with fly ash are presented. A series of experimental works are performed to find out the compaction characteristics, strength and swell behaviour of lime treated soil with gypsum and fly ash. The samples collected after completion of experimental works are used for micro–analysis (X–ray diffraction and scanning electron microscope). The results show that use of fly ash enhances the strength of lime treated gypseous soil by 1.92 folds. Also, the rapid swell, which is observed in gypseous soil with lime treatment, is reduced by 33% after using fly ash. The micro–analysis confirms that formations of cementitious compounds such as calcium silicate hydrate (CSH), calcium aluminum oxide hydrate (CAOH), calcium aluminum silicate hydroxide hydrate (CASHH) and ettringite needles lead to change in the geotechnical properties of soil. Further, it has been found that availability of water influences significantly on the formation of ettringite minerals and, thereby subsequent changes in properties of soil.

The practice of treating different soil with fly ash and lime is an attractive proposition and is... more The practice of treating different soil with fly ash and lime is an attractive proposition and is widely applied in the field of geotechnical engineering. However, the use of fly ash to combat the susceptible behaviour of lime treated sulfate/gypseous soil is still a debatable issue, and hence, is a matter of current research. Currently, efforts are being made to identify whether fly ash has the potential to overcome deficiencies observed in lime treated gypseous soil. This study evaluates the strength and volume change behaviour of lime treated soil containing varying gypsum content with fly ash after curing for different periods. The results revealed that fly ash improves the strength of lime treated gypseous soil continuously with increase in curing periods but promotes the swell in the lime treated gypseous soil. However, the swell in lime treated gypseous soil with fly ash eliminates completely with curing period. Detailed physico–chemical and micro–analyses (mineralogical and microstructural) have been performed on the samples collected after completion of strength and swell tests to elucidate the mechanism of these behavioral changes. The evidences confirmed the formation of cementitious compounds of different composition and ettringite crystals of different amounts having different aspect ratios. However, the supply of additional alumina and silica by the fly ash to lime treated gypseous soil and water are the key factors for potential use of fly ash to improve the properties of lime treated gypseous soil.

An attempt was made to study the efficiency of fly ash and lime on the volume change behavior of ... more An attempt was made to study the efficiency of fly ash and lime on the volume change behavior of soil to mask the effect of gypsum. Swell and compressibility of soil mixed with 10 % fly ash and treated with various lime contents (0 %–6 %) in the absence and presence of 1 % gypsum after curing for different periods of up to 28 days were studied. It was established that an increase in lime content improved swell and compressibility in the soil-fly ash mix but that it led to rapid swelling and increased compressibility in the presence of gypsum, particularly when the specimens were not cured. Higher amounts of lime and a longer curing period were found to be essential to conquer the adverse effect of gypsum. The behavioral changes in the swell and compressibility of both specimens, with and without gypsum, were attributed to consequent alterations in the microstructure by the formation of cementitious products and the growth of ettringite crystal. It was observed that the formation of cementitious compounds with a curing period enables to the compound to overcome the adverse effect of ettringite, leading to control of undesirable volume change behavior.

Series of oedometer tests and micro-analytical studies (XRD, SEM and EDAX) have been carried out ... more Series of oedometer tests and micro-analytical studies (XRD, SEM and EDAX) have been carried out to investigate the influence of varying gypsum content on swell, compressibility and permeability of lime treated montmorillonitic soil after curing for different period. Immediate swell is observed on inundation of compacted samples with water and continuously increased with gypsum content. However, changes in swell are found to be marginal with curing. This is attributed to the formation and growth of ettringite crystals by ionic reactions of aluminum–calcium–sulfate in the presence of water which is confirmed through detailed micro-analysis. The higher swell in uncured specimens and gradual reduction in swell with increase in curing periods are due to relative dominance of formation and growth of ettringite and cementitious compounds, respectively. Also, the ionic reaction products are found to bear a significant influence on the compressibility and permeability behavior.

Temporal variation in moisture content induces more problematic characteristics in expansive soil... more Temporal variation in moisture content induces more problematic characteristics in expansive soil. The soil undergoes change in its behavior from hard (at dry condition) to soft (at wet condition). Various pozzolanic additives such as lime as well as waste materials like fly ash are used to strengthen the soil. Depending upon chemical and mineralogical composition of the additives, the strength
improvement in the soil can vary. This paper presents the variation in the strength of soil by addition of hydrated lime, fly ash alone as well as admixtures of fly ash-lime, and fly ash-lime-gypsum. Both short term and long term variations in strength of soil has been studied. It has been observed that the response of the soil with curing period to each additive or its combination is considerably different. An attempt has
been made to deduce the governing mechanisms in strength development through the alteration in mineralogical, microstructure and chemical composition. For this study, X-ray diffraction, scanning electron microscope and energy dispersive spectroscopy analysis are carried on fractured portion of samples after testing for unconfined compressive strength samples. It has been clearly brought out that formation of
cementitious materials (C-S-H, C-A-H and C-A-S-H-H) in soil with lime and alteration with the use of fly ash and gypsum play significant role in improving the strength. The changes in microstructure of the soil with the formation of new compounds are related with chemical composition (Al:Si, Al:Ca and Ca:Si) that in turn are related to variations in the strength behavior of soil.

A closed-form solution is presented in this paper for the prediction of stress and displacements ... more A closed-form solution is presented in this paper for the prediction of stress and displacements around circular openings in a brittle rock mass subject to a hydrostatic stress field. The rock mass is assumed to be brittle plastic for Hoek-brown yield criterion and perfectly plastic for Mohr-Coulomb Criterion. For the elastic-brittle-plastic analysis of circular openings in an infinite Hoek-Brown medium, the existing analytical solutions were found to be incorrect. These methods, however, are based on simplifying assumptions with respect to geometry, material behavior and boundary conditions. So, analytical solutions can be rarely of practical concern to rock mechanics problems. As rock consists of complex formations and exit a wide range of behaviors, the analytical methods provide only approximate solutions. Hence, a conceptual tool, using numerical methods called Finite Element Method (FEM) has been generated and used for realistic prediction of the behavior of the complex underground excavations in rock mass at various in-situ stress conditions.
The closed-form solution is validated by using the finite element method. In the finite element analysis, the constitutive model frequently used in numerical calculations of tunnel excavation is linear-elastic perfectly plastic Mohr-Coulomb (MC) failure criterion. Generally, this leads to shallower and wider surface settlement than those observed experimentally. In this research, constitutive model is implemented in a two-dimensional simulation of an underground excavation in a plane strain: a linear-elastic perfectly plastic (the Mohr-Coulomb model) model. Stresses and deformations of different shapes of tunnels using these constitutive models implemented in commercial software (PLAXIS) are evaluated.

Talks by Arvind Jha

Teaching Documents by Arvind Jha

Ministry of Local Development DDC/DTO, Dhanusha Quality Ass urance Plan for Bridge Construction F... more Ministry of Local Development DDC/DTO, Dhanusha Quality Ass urance Plan for Bridge Construction Foreword to the Bridges Quality Assurance Plan The Quality Assurance Plan maps out what, when and how things will be done. It is a blueprint for a successful job. The current Bachharaja river bridge construction programme, apart from donor supported one, includes a large number of structures, among which a significant proportion are 25m span. These are major structures by any standard, and involve a huge financial investment by GoN, RAIDP, Nepal. The works are being constructed by national contractors, often with limited resources, and are supervised by DDC/DTO/RAIDP staff working under difficult conditions in remote locations. The Bridges QA Plan has been prepared in response to the declared needs of the field staff involved in bridge construction. It covers the major issues raised by those staff, recognizing the l im it ed r es ou r c es available. The doc um ent is i nt en d ed to b ri ng ab out inc rem ent al changes in the management of bridge construction by Contractors, with the longer term objective of improving overall quality of construction. The scope of the QA Plan will be expanded in future revisions as field divisions become familiar with the requirements and implementation of the QA processes.

The use of lime and fly ash to improve the properties of certain types of soil is well establishe... more The use of lime and fly ash to improve the properties of certain types of soil is well established. However, the potential of fly ash to control the adverse effects of lime-treated gypseous/sulphatic soil has not been well investigated. In the present work, an attempt is made to quantify the fly ash content used to suppress the susceptible behavior of lime-treated gypseous soil. Series of one-dimensional swell and compressibility analyses are performed on various combinations of expansive soil with a predominance of montmorillonite mineral containing lime, gypsum (0–6%), and fly ash (0–30%). It is observed that the volume change behavior of the lime-treated gypseous soil is not controlled completely by addition of fly ash. However, the maximum improvement in the volume change behavior of the lime-treated gypseous soil is observed with a 20% fly ash content, and hence, can be taken as the Optimum Fly ash Content (OFC). Micro-analyses revealed that the relative dominance of the change in gradation and the formation of cementitious compounds of different compositions and ettringite crystals are the key factors in controlling the volume change behavior of lime-treated gypseous soil with fly ash. However, several factors, such as the types of minerals present in the soil, the types of fly ash and lime, and other physico-chemical environmental conditions (temperature, method of curing, and so on), are seen in the present study to affect the value of the obtained OFC.

Geo-climatic environmental conditions lead to the formation of gypsum-rich soils which occur in d... more Geo-climatic environmental conditions lead to the formation of gypsum-rich soils which occur in dry condition throughout world where the annual quantity of rain water is insufficient for leaching the gypsum from these soils. Soils containing gypsum, also known as gypseous/gypsiferous soil, are not preferred as a construction material; however, the scarcity of land and an increase in the utilization of soils for construction purpose have drawn an attention of research community to address the associated problems for its effective uses. The present article reviews the physico-chemical behaviour of gypsum, sources of gypsum in the soils, and also reveals the misconceptions on the suitable terminology used for soil containing gypsum. Further, the various methods proposed to identify the gypsum containing soil are discussed. The problems due to the phase transformation and its solubility characteristics of gypsum on the different construction activities are also reviewed in brief. The purpose of present article is to acquaint the impact of gypsum in the properties of different soils and to bring out the different methods available for stabilizing the gypsum containing soil. The refinements herein proposed aim to help understand the various aspects of gypseous soil and to institute the further research to be done in this topic.

An attempt has been made to examine the role of fly ash content (0–30%) to control undesirable st... more An attempt has been made to examine the role of fly ash content (0–30%) to control undesirable strength loss in lime–treated expansive soil containing gypsum (0–6%) after curing for different periods up to one year. Further, detailed experimental investigations have been performed to assess the plasticity, swell index and compaction behavior of soil treated with these additives. Results of the strength behavior revealed that a significant effect of higher fly ash content in the strength development of lime–treated soil is observed after longer curing periods. Presence of increasing amounts of gypsum accelerates early strength gain initially, but reduces long–term strength gain in soil–lime–fly ash mixes. Fly ash improves the strength of lime–treated gypseous soil. However, beneficial use of fly ash to improve the strength of lime treated gypseous soil depends on the amount of gypsum present in the soil and length of curing periods. Micro–analyses (XRD and SEM) revealed that the strength development is controlled by reaction products formed such as cementitious compounds and ettringite crystals.

The interaction of ions (calcium, alumina, silica, and sulfate) in the presence of water is very ... more The interaction of ions (calcium, alumina, silica, and sulfate) in the presence of water is very complex to indentify, and hence, to predict the behaviour of soil. An attempt has been made to understand the mineralogical and micro–structural changes due to soil–lime–gypsum reactions. Further, the associated mechanisms behind changes in the properties of lime treated gypseous soil with fly ash are presented. A series of experimental works are performed to find out the compaction characteristics, strength and swell behaviour of lime treated soil with gypsum and fly ash. The samples collected after completion of experimental works are used for micro–analysis (X–ray diffraction and scanning electron microscope). The results show that use of fly ash enhances the strength of lime treated gypseous soil by 1.92 folds. Also, the rapid swell, which is observed in gypseous soil with lime treatment, is reduced by 33% after using fly ash. The micro–analysis confirms that formations of cementitious compounds such as calcium silicate hydrate (CSH), calcium aluminum oxide hydrate (CAOH), calcium aluminum silicate hydroxide hydrate (CASHH) and ettringite needles lead to change in the geotechnical properties of soil. Further, it has been found that availability of water influences significantly on the formation of ettringite minerals and, thereby subsequent changes in properties of soil.

The practice of treating different soil with fly ash and lime is an attractive proposition and is... more The practice of treating different soil with fly ash and lime is an attractive proposition and is widely applied in the field of geotechnical engineering. However, the use of fly ash to combat the susceptible behaviour of lime treated sulfate/gypseous soil is still a debatable issue, and hence, is a matter of current research. Currently, efforts are being made to identify whether fly ash has the potential to overcome deficiencies observed in lime treated gypseous soil. This study evaluates the strength and volume change behaviour of lime treated soil containing varying gypsum content with fly ash after curing for different periods. The results revealed that fly ash improves the strength of lime treated gypseous soil continuously with increase in curing periods but promotes the swell in the lime treated gypseous soil. However, the swell in lime treated gypseous soil with fly ash eliminates completely with curing period. Detailed physico–chemical and micro–analyses (mineralogical and microstructural) have been performed on the samples collected after completion of strength and swell tests to elucidate the mechanism of these behavioral changes. The evidences confirmed the formation of cementitious compounds of different composition and ettringite crystals of different amounts having different aspect ratios. However, the supply of additional alumina and silica by the fly ash to lime treated gypseous soil and water are the key factors for potential use of fly ash to improve the properties of lime treated gypseous soil.

An attempt was made to study the efficiency of fly ash and lime on the volume change behavior of ... more An attempt was made to study the efficiency of fly ash and lime on the volume change behavior of soil to mask the effect of gypsum. Swell and compressibility of soil mixed with 10 % fly ash and treated with various lime contents (0 %–6 %) in the absence and presence of 1 % gypsum after curing for different periods of up to 28 days were studied. It was established that an increase in lime content improved swell and compressibility in the soil-fly ash mix but that it led to rapid swelling and increased compressibility in the presence of gypsum, particularly when the specimens were not cured. Higher amounts of lime and a longer curing period were found to be essential to conquer the adverse effect of gypsum. The behavioral changes in the swell and compressibility of both specimens, with and without gypsum, were attributed to consequent alterations in the microstructure by the formation of cementitious products and the growth of ettringite crystal. It was observed that the formation of cementitious compounds with a curing period enables to the compound to overcome the adverse effect of ettringite, leading to control of undesirable volume change behavior.

Series of oedometer tests and micro-analytical studies (XRD, SEM and EDAX) have been carried out ... more Series of oedometer tests and micro-analytical studies (XRD, SEM and EDAX) have been carried out to investigate the influence of varying gypsum content on swell, compressibility and permeability of lime treated montmorillonitic soil after curing for different period. Immediate swell is observed on inundation of compacted samples with water and continuously increased with gypsum content. However, changes in swell are found to be marginal with curing. This is attributed to the formation and growth of ettringite crystals by ionic reactions of aluminum–calcium–sulfate in the presence of water which is confirmed through detailed micro-analysis. The higher swell in uncured specimens and gradual reduction in swell with increase in curing periods are due to relative dominance of formation and growth of ettringite and cementitious compounds, respectively. Also, the ionic reaction products are found to bear a significant influence on the compressibility and permeability behavior.

Temporal variation in moisture content induces more problematic characteristics in expansive soil... more Temporal variation in moisture content induces more problematic characteristics in expansive soil. The soil undergoes change in its behavior from hard (at dry condition) to soft (at wet condition). Various pozzolanic additives such as lime as well as waste materials like fly ash are used to strengthen the soil. Depending upon chemical and mineralogical composition of the additives, the strength
improvement in the soil can vary. This paper presents the variation in the strength of soil by addition of hydrated lime, fly ash alone as well as admixtures of fly ash-lime, and fly ash-lime-gypsum. Both short term and long term variations in strength of soil has been studied. It has been observed that the response of the soil with curing period to each additive or its combination is considerably different. An attempt has
been made to deduce the governing mechanisms in strength development through the alteration in mineralogical, microstructure and chemical composition. For this study, X-ray diffraction, scanning electron microscope and energy dispersive spectroscopy analysis are carried on fractured portion of samples after testing for unconfined compressive strength samples. It has been clearly brought out that formation of
cementitious materials (C-S-H, C-A-H and C-A-S-H-H) in soil with lime and alteration with the use of fly ash and gypsum play significant role in improving the strength. The changes in microstructure of the soil with the formation of new compounds are related with chemical composition (Al:Si, Al:Ca and Ca:Si) that in turn are related to variations in the strength behavior of soil.

A closed-form solution is presented in this paper for the prediction of stress and displacements ... more A closed-form solution is presented in this paper for the prediction of stress and displacements around circular openings in a brittle rock mass subject to a hydrostatic stress field. The rock mass is assumed to be brittle plastic for Hoek-brown yield criterion and perfectly plastic for Mohr-Coulomb Criterion. For the elastic-brittle-plastic analysis of circular openings in an infinite Hoek-Brown medium, the existing analytical solutions were found to be incorrect. These methods, however, are based on simplifying assumptions with respect to geometry, material behavior and boundary conditions. So, analytical solutions can be rarely of practical concern to rock mechanics problems. As rock consists of complex formations and exit a wide range of behaviors, the analytical methods provide only approximate solutions. Hence, a conceptual tool, using numerical methods called Finite Element Method (FEM) has been generated and used for realistic prediction of the behavior of the complex underground excavations in rock mass at various in-situ stress conditions.
The closed-form solution is validated by using the finite element method. In the finite element analysis, the constitutive model frequently used in numerical calculations of tunnel excavation is linear-elastic perfectly plastic Mohr-Coulomb (MC) failure criterion. Generally, this leads to shallower and wider surface settlement than those observed experimentally. In this research, constitutive model is implemented in a two-dimensional simulation of an underground excavation in a plane strain: a linear-elastic perfectly plastic (the Mohr-Coulomb model) model. Stresses and deformations of different shapes of tunnels using these constitutive models implemented in commercial software (PLAXIS) are evaluated.