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Civil Engineering
Civil Engineering is a profession of designing and executing structural works that serve the general public, like houses, buildings, roads, etc. A Civil Engineer is an engineer trained in the design and construction of public works, such as bridges or dams, and other large facilities.
4,921 Questions
What are advantages of concrete slump test?
when we pour any material i.e, sand or gravel or any other material on ground it takes conical shape . Because, every particle has its own angle of internal friction. To maintain its angle of internal friction it takes the shape of the cone. so the reason why we prefer the slump test apoparatus in that shape.
What is the difference between cast in situ and precast concrete?
Pre-cast concretes are manufactured in a pre-cast plant or on site (tilted-up construction). Cast in steel moulds with precise dimension. Very good quality control. Delivered and erected on site.
Cast in-situ are constructed on site using fresh concrete from trucks and placed by workers. Quality Control is the responsibility of the site manager.
What is the Bulk Density of crushed concrete?
The density of crushed concrete varies depending on the gradation and quantity of impurities (e.g. asphalt and other) but can be estimated at 1900-1950 kg/m^3.
What is the ratio of cement and sand and crused stone in mix concrete of M-10 value?
1:2:4 i.e. i cement, 2 sand and 4 aggregate...
The primary reason beavers build dams is to protect themselves from predators like bears, hawks, wolves, wildcats, and otters and to secure easy access to food, especially during the colder months.
What is high grade-tensile steel?
Classification of high grade-tensile steel for Automotive: Automotive steels can be classified in several different ways. One is a metallurgical designation. Common designations include low-strength steels (interstitial-free and mild steels); conventional high-tensile or high-strength steels, otherwise called HSS (carbonmanganese, bake hardenable, high-strength interstitial-free, and high-strength, low-alloy steels); and the newer types of ultra-high tensile or Advanced High-Strength Steels, called AHSS (dual phase, transformation-induced plasticity, complex phase, and martensitic steels). Additional higher strength steels for the automotive market include ferritic-bainitic, twinning-induced plasticity, hot-formed, and post-forming heat-treated steels.
A second classification method important to part designers is strength of the steel. In this answer, the general terms HSS and AHSS is used to designate all higher strength steels. In contrast, much of the current literature in the world today uses narrowly defined ranges to categorize different steel strength levels. One such system defines High-Strength Steels (HSS) as yield strengths from 210 to 550 MPa and tensile strengths from 270--700 MPa, while Ultra-High-Strength Steels (UHSS) steels have yield strengths greater than 550 MPa and tensile strengths greater than 700 MPa. These arbitrary ranges suggest discontinuous changes in formability when moving from one category to another. However, data show property changes are a continuum across the entire span of steel strengths. In addition, many steel types have a wide range of grades covering two or more strength ranges.
A third classification method presents various mechanical properties or forming parameters of different steels, such as total elongation, work hardening exponent n, or hole expansion ratio .
The principal difference between conventional HSS and AHSS is their microstructure. Conventional HSS are single phase ferritic steels. AHSS are primarily multi-phase steels, which contain ferrite, martensite, bainite, and/or retained austenite in quantities sufficient to produce unique mechanical properties. Some types of AHSS have a higher strain hardening capacity resulting in a strength-ductility balance superior to conventional steels. Other types have ultra-high yield and tensile strengths and show a bake hardening behaviour.
Who designed the first truss bridge?
the first Truss bridge was built by Palmer in 1811 in Philidelphia
Which is stronger a plank bridge or a arch bridge?
An arch bridge. I think that may have been discovered quite some time ago !!!
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It was - the Romans used arches extensively, in buildings as a well as for bridges. However, the arch is indeed stronger than the plank, or simple beam, bridge because it transmits the loads to its abutments. You can stiffen a beam bridge by fitting it with vertical side-members, or in larger structures, frames (trusses).
Difference between ordinary Portland cement and puzzalona Portland cement?
- OPC - Ordinary Portland cement
- OPC - Materials used - Argillaceous and calcareous materials
- PPC - Portland Pozzolona Cement
- PPC - OPC + Pozzolonoc materials(fly ash, volcanic ash, pumicite at the time of grinding).
How much does a robotics engineer earn?
The average salary of a robotics engineer is $52,857 per year. Some robotics engineers can earn up to $75,865 per year.
What is criteria for selection of site of dam?
The site should have enough capacity to hold water for desired number of years. It should also have some source of water inlet.
What is tensile strength of concrete?
The tensile strength of concrete is 10% of it's compressive strength.
What is the invert level for manholes and inspection chamber?
the lowest level of outgoing orifice where there are numerous inlet & out pipes connecting a manhole.
Bleeding in concrete is sometimes referred as water gain. It is a particular form of segregation, in which some of the water from the concrete comes out to the surface of the concrete, being of the lowest specific gravity among all the ingredients of concrete. Bleeding is predominantly observed in a highly wet mix, badly proportioned and insufficiently mixed concrete. In thin members like roof slab or road slabs and when concrete is placed in sunny weather show excessive bleeding.
Due to bleeding, water comes up and accumulates at the surface. Sometimes, along with this water, certain quantity of cement also comes to the surface. When the surface is worked up with the trowel, the aggregate goes down and the cement and water come up to the top surface. This formation of cement paste at the surface is known as "Laitance". In such a case, the top surface of slabs and pavements will not have good wearing quality. This laitance formed on roads produces dust in summer and mud in rainy season.
Density table for different materials?
TABLE OF DENSITY FOR SOME COMMON MATERIALS (computed in grams per cubic centimeter) COMMON MATERIALS Water ………………………1.00 Glass………………………2.60 Granite……………………...2.650 Bone……………………….1.85 Human Body………………..0.995 Butter……………………...0.94 Ice…………………………...0.917 Carbon…………………….2.60 Kerosene……………………0.800 Chalk………………………2.36 Salt………………………….2.200 Coal………………………..1.50 Sand…………………………2.800 Cork………………………..0.25 Sulfuric Acid………………..1.840 Gasoline……………………0.72 COMMON METALS Aluminum…………………..2.70 Mercury……………………13.60 Brass………………………...8.40 Nickel………………………8.80 Chromium…………………..7.10 Platinum……………………21.50 Copper………………………8.63 Silver……………………….10.40 Gold…………………………19.30 Tin………………………….7.30 Iron………………………….7.80 Uranium……………………18.70 Lead…………………………11.30 Zinc…………………………6.90 Magnesium………………….1.74 SOME COMMON WOODS Alder………………………0.40 White Pine…………………0.43 Ash………………………..0.75 Maple………………………0.69 Balsa………………………0.12 Oak…………………………0.85 Douglass fir……………….0.56 Yellow Pine………………...0.46 Ebony……………………..1.20 Walnut……………………..0.67 Larch (tamarack)………..0.51
Were tunnels used in the fighting during World War 1?
yes they were they played a very important role in destroying German trenches. the English had an elite group of tunnelers that worked in total silence. they dug tunnels under German lines then planted tnt and blow up the Germans trenches
What is done to stop bridges from rusting?
Metal comes in contact with oxygen. That's the main reason that many mechanics wipe down their older metal tools with oil (WD-40). The coat of oil prevents air from contacting the metal. That's why they spend much more than $100,000 to paint a bridge. The coat of paint saves them. H2O, water, has the same effect on metal.
Why the actual strength of a metal is lower than its predicted ideal strength?
Because in theory we study regarding a perfect material but in reality the material will have many imperfections which decreases the stress required to deformed a material.
What is difference between the open channel and closed channel flow?
open cahannel flow and pipe flow
Open channel is always at atmospheric pressure
Pipe flow has pressure either above or below atm
Which are seminar topics in water resources engineering?
Seminar Topic in Structural Engineering are as under.
1. Fibre Reinforced Cements and Concretes: Recent Developments.
2. Techniques for the Seismic Rehabilitation of Existing Structures.
3. Seismic Assessment and Upgrading of Existing Structures.
4. Role of Building Codes in Seismic Assessment.
5.Seismic Retrofitting of RC Buildings Using Traditional Techniques.
6. Recent Advances in Seismic Retrofitting of RC Frames.
7. Smart Material and Smart Structures.
8. Deep Foundations Case Histories: Innovations in Design, Methods and Equipment.
* Revised, improved and consistent notations throughout code * Effect of multiple edges on anchor capacity * Design of post-installed anchors used in cracked and uncracked concrete * Unified design provisions for reinforced and prestressed concrete flexural and compression members * Shear reinforcement at slab-column connections of slabs that are not part of the lateral-force-resisting system of a building in a high seismic design category * Development length requirements in seismic force-resisting members * Application of unified crack control criteria to flexural tension reinforcement as well as skin reinforcement in deep beams * Alternate torsion design procedure for L-shaped solid beams that have a large height-to-width ratio Also covered in this seminar are the following topics: * Adjustment of allowable tension reinforcement stresses for crack control * Shear in precast, prestressed concrete hollow-core units * Drop panels for enhanced punching shear resistance, or for reduction of the amount of negative reinforcement over a column or to satisfyminimum required slab thickness * Modified strength reduction factor for flexural sections within the development length of pretensioned members * Spiral reinforcement with yield strength up to 100,000 psi * Construction joint locations in continuous post-tensioned beams and slabs * Clarification of design procedure for pile caps * Reduced maximum allowable tensile stresses in the concrete of post-tensioned slabs * Documents applicable to non-structural, soil-supported slabs
