Civil Engineering

This study introduces a test examination on self-compacting concrete (SCC) with fine total (sand) substitution of a Quarry Dust (QD) (0%, 25%, half, 75%,100%) and expansion of mineral admixtures like Fly Ash (FA) and Silica Fume (SF) and synthetic admixtures like super plasticizers (SP). After every blend arrangement, 45 3D shapes examples and 45 chambers examples are thrown and cured. The examples are cured in water for 3, 7 and 28 days. The droop, V-channel and L-Box test are done on the new SCC and in solidify concrete compressive quality and split elasticity qualities are resolved. Endeavors have been made to examine the properties of such SCCs and to explore the appropriateness of Quarry Dust to be utilized as fractional trade materials for sand in SCC.

Using of tuned mass damper is a common way for reducing responses of structures as a result of wind and earthquake. This damper is consisted of concentrated mass which is connected to the point of structure by a damper and spring. In this paper frame of last floor is used for placing tuned mass damper. For this reason, four models of 4, 8, 12, 20 floor buildings with moment resistance frame are studied under effect of earthquakes of near field Leandros, Northrdig, Kube and Tabas faults. So, mass damper which is suggested on the base of improved values in scientific resources is calculated. On the base of these results, it is possible to found appropriate behavior of tuned mass damper in 12 and 20 buildings.

In today’s era, majority of the residential construction involves masonry. Despite its wide use in structural engineering, masonry is still the least understood especially seismic behavior building material in terms of strength and deformation characteristics due to its heterogeneity. The general behavior of unreinforced masonry under lateral is brittle and thus has high seismic hazard. Confining masonry is found to enhance the seismic behavior of masonry. In this project simple masonry (unreinforced masonry) and confined masonry walls of size 1.25mx1.25mx.1m were tested and compared for their behavior under in plane lateral loads. Confinement to the masonry was provided in the form of reinforced vertical columns and horizontal beam called as tie columns and tie beam respectively. The reinforcement in confinement was provided as per the guidelines issued by Euro code 8 for confined masonry. Their ultimate load strength, deformation capacity (ductility) and initial stiffness are the parameters studied in comparison. Confined masonry showed excellent behavior under lateral loads both in terms of ultimate load capacity and ductility than the simple masonry.

About 1% of the total storage capacity in the world’s reservoirs is lost annually due to sedimentation. Sediments can also block intakes in reservoirs and damage tunnels or turbines. One of the most effective techniques to remove these sediments is flushing, whereby water level is lowered sufficiently to re-erode deposits and flush them through the intakes. Outflow sediment discharge may well be related to the parameters such as the sediment characteristics in the reservoir, sediment discharge and hydrological conditions. In this paper, investigation and evaluation of sedimentation and flushing in Dez1 stream dam are considered. Sensitivity analysis of the mathematical model is evaluated for input parameters variation on sedimentation and flushing in reservoirs. Results shows that the rate of sediment flushing is strongly associate with grain size of sediment. This paper shows that flushing can retrieve about 50% of beneficial storage of reservoirs.

Extensive cracking on the runway slabs at the Srinagar (Jammu & Kashmir) International Airport has taken place due to overloading of aircraft operations and poor sub grade stability. A visual crack survey was carried out. The survey detected cracks of width of less than 6.4 mm to more than 50 mm which were classified into four types according to their width of opening. Repair methodologies were developed for each category of crack. The repair works and the construction of the overlay were carried out at night as the runway has to be kept operational. The runway has been in service and no sign of distress has been observed since the completion of repair works and overlay construction in September 2010.

Effect of glass grid as high tensile strength layer in rigid pavements /runways has been studies using model slabs of low slump value and high strength concrete M40 (40N/mm2) with flexural strength of 4.4 N/ mm2,desighned for 1800kg gross load with 1200 repetition casted over the same sub grade on which runways was to be reconstructed .The slabs after subjected to loads shows that there occurs least number of cracks with less width and propagate to lesser depths and non –continues in nature by the use of glass grids as secondary reinforcement also there is considerable arrest of reflective cracks in case of rigid overlays over cracked pavement.

Stress?Strain response of sands focusing sand’s shearing stress, angle of shearing resistance, dilatancy and contraction during volumetric changes etc. is of highly research interest due to its application in soil modelling and prediction of soil hazards even in a case of soil liquefaction. In this research paper, grain size and state of compactness (loosest and densest) influence on the stress?strain response of 8 (eight) different and specific sized granular sand grain have been researched by analyzing the results of a digital direct shear test corresponding to a constant strain rate of 0.5 mm / minutes and increasing normal load (5 kg, 10 kg and 15 kg). In a bird’s eye view of the results, shearing stress (irrespective of compaction state) increases only 4 % from smaller to larger grain whereas approximately 30 % increase is discernible in dense grain than that of loose grain (irrespective of grain size). Larger sized grain possesses approximately 1.5 times more angular shear resistance than smaller size but in densest state it is about 2 times more. Authors have opined that, Though both the grain size and state of compactness (loosest and densest) affects the stress?strain response, state of compactness reveals more significant influence. In a dilation?contraction region, a loose grain contracts (18 %) while a dense grain contracts initially (15 %) but finally dilates (21 %) for an increase of size during plastic volumetric deformation of the grain.

The effect of cassava peel ash on Lateritic Stabilized with Bitumen was investigated. The lateritic solid was collected from Umuma-Isiaku in Ideato South LGA of Imo State. The Bitumen was collected from New Idea Construction Company Ltd in Owerri. The Cassava peel was collected from Ohaji in Egbema LGA OF Imo State. The Cassava Peel was burnt in a furnace and sieved with 150% sieve to obtain the ahs used in the experiment. The lateritic soil was classified as A-2-7 on AASHITO classification chart. The percentage replacement level of soil by Bitumen and Bitumen/cassava peel ash 0-10% by weight of dry soil. The investigation was carried out with respect to compaction Characteristic and California Bearing Ratio (CBR) tests. The result obtained indicated a decrease in maximum Dry Density (MDD) when the soil was stabilized with bitumen and increases when cassava peel ash was incorporated for 0-10% replacement level of soil with bitumen and bitumen/cassava peel ash respectively. The result of the optimum moisture content (OMC) increases when bitumen was used in stabilizing the soil and decreases when cassava peel ash was incorporated. The result of the MDD when bitumen was used in stabilizing the soil ranges from 2.16-1.76gkmcm3 for 0-10% replacement of dry soil with bitumen and 2.16-4.20g/cm3 when cassava peel ash was incorporated. The results of OMC ranges from 11.20 -21.90% and 11.20-8.80% for 0-10% replacement of dry soil with bitumen and bitumen/cassava peel ash respectively. The result of CRR text ranges from 22.66-85.75% and 22.66-18.10% for the same replacement level of bitumen and bitumen/cassava peel ash respectively. These results shows that the high shear strength of soil which was achieved by stabilizing the soil with bitumen was reduced by the incorporation of cassava peel ash.

The influence of polypropylene fibers has been studied to improve the mechanical properties of lightweight concrete with Waste of Thermostone blocks used to produce lightweight coarse aggregate. The volume fractions of the polypropylene fibers (P.P.F.) used are: 0.0% for reference light weight concrete, and 0.25%, 0.5%, 0.75%, 0.1%, and 1.25% total volume of concrete for other mixes. The density, compressive strength and splitting tensile strength, Flexural strength, and water absorption were measured. The results shows, generally, the mechanical properties of lightweight concrete increased with rising the percentages of polypropylene fibers. With P.P. fibers proportioning 1.0% at 28 days caused 13.93% increase in compressive strength and 43.65% increase in the splitting tensile strength and 41.69%increase in the flexural strength, therefore, it is used as the optimum proportion of the polypropylene fibers. The flowability of lightweight concrete reduced by addition polypropylene fibers, therefore Super plasticizer was used to improve the workability of fresh light weight concrete. The equilibrium densities of structural lightweight concrete method was used to determine the density of Lightweight P.P.F. and was 1789Kg/m3. Also, the results showed that there are increases in the water absorption for mixes with P.P.F.as compared with reference mix..

Climatic responsive buildings are examples of a sensitive approach to energy consciousness for indoor comfort conditions. It has now become essential to develop energy efficient building design. The basis requirement of a building is to provide thermal comfort to its occupants. In modern buildings this is usually accomplished with the help of mechanical cooling or heating. With the advent of energy crisis there has been a need to develop climatic design tools which will provide thermal comfort in a building without or with minimum expenditure of energy. Climate determines the amount of solar radiation and mean outside temperature that a building is exposed to. Buildings are experiencing overheating during summer. For a built form, vertical surfaces are the most critical to the impact of solar radiation. This study examines the effect of different plan forms on the total solar radiation received by vertical surfaces of the buildings. The aim of this paper is to analyse the climatic conditions with respect to thermal comfort in buildings for the location of Bhubaneswar. The impact of building location and orientation on thermal comfort has been investigated. Different building shapes (square and rectangular) have been studied with variations in width-to-length ratio (aspect ratio) and building orientation. This study guides designers on choosing optimum form and appropriate orientation for buildings. The present paper describes how different plan forms are affected by solar radiation. Based on that the optimum aspect ratio (Length: Width) of the building over the location of Bhubaneswar has been found out which will receive minimum radiation in summer and maximum radiation in winter. This result in significant saving in the energy consumed while creating comfortable indoor environment.