i-manager's Journal on Civil Engineering (JCE)


Volume 6 Issue 1 December - February 2016 [Open Access]

Research Paper

Experimental Study on Motion Responses of a Damaged Semi-Submersible for Head Sea and Beam Sea Directions of Incident Waves

Sayed Mohammadmehdi Jamal* , Keyvan Sadeghi**
* Graduate Student, Civil Engineering Department, Hormozgan University, Hormozgan, Iran.
** Assistant Professor, Buein Zahra Technical University, Qazvin, Iran.
Jamal,S,M., and Sadeghi,K. (2016). Experimental Study on Motion Responses of a Damaged Semi-Submersible for Head Sea and Beam Sea Directions of Incident Waves. i-manager’s Journal on Civil Engineering, 6(1), 1-10. https://doi.org/10.26634/jce.6.1.3745

Abstract

In recent years, due to the reduction of oil resources, both on lands and in shallow waters, exploration and extraction of oil resources are played in deeper waters. Therefore, the need for appropriate structures suitable for deep waters is obvious. The semi-submersible platform is a specific type of such platforms which is used in deep waters. These platforms are utilized for different purposes such as drilling, exploration, extraction, loading and off-loading of petroleum products under the influence of external forces caused by wind, waves, current, etc. True understanding of the dynamical behavior of the semi-submersible platform in damaged condition can help designers to reduce the environmental hazards. Platform structural damage can be accompanied with the entry of water in the reservoirs of platforms which will lead to the change in platform stability and excessive increase in the platform movements. In this research, the AMIRKABIR semi-submersible platform is modeled in the Marine Engineering laboratory of the “Sharif University of Technology”. The model scale was 1:143 and the environmental conditions of the Caspian Sea were considered the amount of water entering one of the pontoon reservoirs was set to follow that similarity scales. The model was installed in the flume tank using a spread mooring system. For the environmental conditions of the Caspian Sea, the platform was tested under both head and beam sea directions. The results of the conducted tests are represented by platform motion Response Amplitude Operators (RAOs).

Research Paper

Design Consideration in Horizontal Flow Grit Chamber for Water and Wastewater Treatment Plant

Manish Kumar* , Shri Ram**
* Design Engineer, Aastha Enviro Engineers Pvt. Ltd., Gurgoan , Haryana, India.
** Associate Professor, Department of Civil Engineering, M.M.M.U.T, Gorakhpur, U.P, India.
Kumar,M., and Shriram (2016). Design Consideration in Horizontal Flow Grit Chamber for Water and Wastewater Treatment Plant. i-manager’s Journal on Civil Engineering, 6(1), 11-20. https://doi.org/10.26634/jce.6.1.3746

Abstract

The objective of the paper is to design Grit Chamber which is efficient for removal of Grits. Separation may be applicable for the different type of methods which may include discrete settling, flocculants settling, compressed settling, accelerated gravity settling. The removal of grit is being done by the process of sedimentation which is being done in the primary phase of water and wastewater treatment. The design of grit chamber is being done on the basis of various parameters which may be in due consideration depending on the influent characteristics, which may lead to design consideration for different treatment plants. Talking of the treatment of wastewater or water, the first phase of treatment is the separation of physical ingredient which are carried away by different means in water and wastewater. Separation of grit is important as going into the system may affect the operation of the wastewater treatment system as it may lead to wear and tear of the Mechanical Equipments. Settling velocity plays the vital role in the design of Grit Chamber which is explained in detail in this paper, as it affects the settling of the particles and also horizontal velocity is made into consideration of the design of Grit Chamber.

Research Paper

Evaluation of Dynamic Elastic Modulus of Roller Compacted Concrete Containing GGBS and M-Sand

S. Krishna Rao* , P. Sravana**, T. Chandrasekhara Rao***
* Research Scholar, Department of Civil Engineering, JNTUH, Hyderabad, Telangana, India.
** Coordinator, Centre for Transportation Engineering, JNTUH, Hyderabad, Telangana, India.
*** Professor, Department of Civil Engineering, Bapatla Engineering College, A.P., India.
Rao,K.S.,, Sravana.P., and Rao,C.T. (2016). Evaluation of Dynamic Elastic Modulus of Roller Compacted Concrete Containing GGBS and M-Sand. i-manager’s Journal on Civil Engineering, 6(1),21-34. https://doi.org/10.26634/jce.6.1.3747

Abstract

Use of industrial by-products such as Ground Granulated Blast furnace Slag (GGBS) as one of the raw materials in Roller Compacted Concrete Pavement (RCCP) is appropriate to deal with the sustainability of concrete and industrial growth. The present experimental investigation assesses the potential of GGBS in roller compacted concrete for pavement applications. The fine aggregate used in the investigation was Manufactured sand (M-sand) in place of natural river sand. The Ultrasonic Pulse Velocities (UPV) was determined at various ages varying from 1 day to 90 days of curing. The GGBS is used as partial replacement of Cement at the range varying from 10% to 60% by weight. The UPV of GGBS Roller Compacted Concrete Pavement (GRCCP) was lower for all mixtures at 1 day when compared to control mix concrete. However as the age of concrete increases the Ultrasonic pulse velocities were appreciably improved for all the mixes. Empirical relationships between strength, UPV and Dynamic Elastic Modulus were proposed. A new model is proposed to determine the Dynamic Elastic Modulus of GRCC.

Research Paper

Flow and Strength Properties of Geopolymer Mortar

shashank* , Suresh Varad**, Praveen Kumar K***, Ram Thilak****
*,***-**** Assistant Professor, Department of Civil Engineering, RV College of Engineering, Bangalore, India.
** PG Student, Structural Engineering, TOCE, Bangalore, Karnataka, India.
Shashank.B.S., Varad,S., Kumar,P.K., and Thilak,R (2016). Flow and Strength Properties of Geopolymer Mortar. i-manager’s Journal on Civil Engineering, 6(1), 35-39. https://doi.org/10.26634/jce.6.1.3748

Abstract

Mortar is a basic ingredient of masonry which helps in binding together the masonry units. The strength and elasticity properties of masonry are not only dependent on the properties of constituent but also on the intricate interaction between the units and the mortar. Thus any study related to the performance of masonry should not exclude studies on mortar. There are quite a good number of mortars which are commonly used that possess relative advantages and disadvantages. These conventional mortars are generally 10-15 mm in thickness. Since these conventional mortars constitute to 7% - 25% of gross volume of masonry, there are manufacturers who have came out with alternative “Geopolymer Bricks” recently. So in this paper, the authors try to find the properties of a Geopolymer mortar. This can be made from alkaline solutions. In this study, an attempt has been made to understand the workability and strength properties of a Geopolymer Mortar. The study includes Geopolymer mortar with different molarities 4M, 8M, and 12M. And also fly ash has been replaced with 10%, 20%, and 30% of Ground Granulated Blast Furnace Slag (GGBS). 1:3 proportion of fly ash to sand ratio has been maintained throughout the work. Based on the study it is found that the workability of fresh Geopolymer mortar decreases with increase in the GGBS replacement. Increase in the compressive strength of the Geopolymer mortar increase with the increase in molarity and compressive strength of the cubes increases up to the replacement of 20% of GGBS for sun curing after which it decreases to a considerable amount.

Research Paper

Static, Modal and Transient Dynamic Analysis of Laminated Composite Plates with Holes

K. Maithry* , B.D.V. Chandra Mohan Rao**
* PG Student, Department of Civil Engineering, VNR Vignana Jyothi Institute of Engineering and Technology, Hyderabad, Telangana, India.
** Professor, Department of Civil Engineering, VNR Vignana Jyothi Institute of Engineering and Technology, Hyderabad, Telangan, India.
Maithry,K., and Rao,C,M,B.D.V. (2016). Static, Modal and Transient Dynamic Analysis of Laminated Composite Plates with Holes. i-manager’s Journal on Civil Engineering, 6(1), 40-47. https://doi.org/10.26634/jce.6.1.3749

Abstract

The use of laminated composites has been increasing day-by-day in various fields of engineering. Laminated composite plates are quite often subjected to dynamic loads and hence it is vital to study the dynamic behavior of such structures. Structural performance of these composite plates need to be evaluated properly, when they are subjected to dynamic loads. The behaviour of laminated composite plates are affected by excessive vibrations, higher displacements and accelerations which may severely deteriorate the structural performance, when they are subjected to dynamic loads such as impulsive loads. So, there is a need to find out a fiber orientation, that produces least dynamic response parameters. Hence, the purpose of this research work is to investigate the dynamic response of the laminated composite plates subjected to excitations, varying arbitrarily with time and to suggest a robust fiber orientation. Laminates may be provided with holes to cater for different purposes in various streams of engineering. Static, Modal and Transient dynamic analysis of laminated composite plates, simply supported at all the edges has been carried out in this study. Laminated composite plates with holes at different positions are investigated for different fiber orientations by considering two types of loadings i.e., Triangular impulsive loading and Rectangular impulsive loading. This part of the research has been carried out using finite element software ANSYS 13.0.

Case Study

Tunnel Construction in Pir Panjal (Himalaya) Using NATM [Case Study T-74R Railway Tunnel of Katra-Banihal Section of Kashmir Rail Project]

Kaiser Bukhari* , Ayaz Mohmood Dar**, Maqbool Yousuf***
* Associate Professor, Department of Civil Engineering, National Institute of Technology, Srinagar, India.
**-***Research Scholar, Department of Civil Engineering, National Institute of Technology, Srinagar, India.
Bukhari,S,K., Dar,A,M., and Yousuf,M. (2016). Tunnel Construction in Pir Panjal (Himalaya) Using NATM [Case Study T-74r Railway Tunnel of Katra-Banihal Section of Kashmir Rail Project]. i-manager’s Journal on Civil Engineering, 6(1), 48-53. https://doi.org/10.26634/jce.6.1.3750

Abstract

The new railway link project between Katra-Banihal is one of the current, most significant Indian projects aiming to join the Kashmir valley with the whole Indian railway network. The T-74R tunnel, going from km 125+310 to km 133+910 (new alignment chainages), is being excavated between the right side of the Bishlari river valley (roughly 5km downstream and southward of Banihal) and the last 5km of the left hillside of its tributary, the valley of the Mahumangat Nallah.The tunnel passes through heterogeneous geology which was highly deformed and having high squeezing property likelihood of heavy water inflow in the limestone zone with heavy overburden. New Austrian Tunnelling Method (NATM) was Preferred over TBM. The New Austrian Tunnelling Method includes a number of techniques for safe tunnelling in rock conditions in which the stand-up time is limited before failure occurs. This paper highlights the various techniques of construction of the tunnel (T-74R) in rugged Himalyan Range.