HGE - Terminologies PDF Past Papers

HGE - TERMINOLOGIES MAY 2015 Surface Tension - the elastic tendency of liquids which makes them acquire the least surface area possible. It is responsible, for example, when an object or insect such as mosquitoes that is denser than water is able to float or run along the water surf...

HGE - TERMINOLOGIES MAY 2015 Surface Tension - the elastic tendency of liquids which makes them acquire the least surface area possible. It is responsible, for example, when an object or insect such as mosquitoes that is denser than water is able to float or run along the water surface. Degree of Saturation - the ratio between the volume of water and the volume of voids. Porosity - the ratio between the volume of void and the volume of the soil mass. Moisture Content - the ratio between the weight of water and the weight of solid particles. NOVEMBER 2015 Archimedes - states the law of buoyancy. Steady Flow - a flow in which the velocity of the fluid at a particular fixed point does not change with time. Cohesion - is the component of shear strength of a rock or soil that is independent of interparticle friction. Liquefaction - a phenomenon in which the strength and stiffness of a soil is reduced by earthquake shaking or other rapid loading. Effective Stress - a pile of sand keeps from spreading out like a liquid because the weight of the sand keeps the grains stuck together in their current arrangement, mostly out of static friction. This weight and pressure called… Gas - not a soil component. (Note: Components of soil are organic materials, minerals, etc.) Sieve Analysis - a practice procedure used to assess the particle size distribution (also called gradation) of a granular material. The size distribution is often called of critical importance to the way the material performs in use. Gravel - according to USCS, is a soil grain with grain size greater than 4.75 mm but less than 75 mm. (75 mm > 4.75 mm) Boulders - particles of rock will not pass a 12 in (200 mm). (200 mm < …) Cobble - particles of rock that will pass a 12in (300 mm) square opening and be retained on a 3in (75 mm). (300 mm > 75 mm) Coarse Aggregate - (75 mm > 19 mm) passes 3in (75 mm) sieve and retains ¾in (19 mm) sieve.  Fine Aggregate - (19 mm > 4.75 mm) passes ¾in (19 mm) sieve and retains No. 4 (4.75 mm) sieve. Location of GWT, depth of backfill and plasticity of soil affects the settlement of footing. Steepness of the fill and steepness of the cut shall not exceed to 1:2 (1 vertical and 2 horizontal). MAY 2016 Turbulent - when the path lines of the individual particles of a flowing liquid are irregular curves and continually cross each other and form a complicated network. Hydraulic gradient - a line joining the points of highest elevation of water in a series of vertical open pipes rising from a pipeline in which water flows under pressure. Water Hammer - a pressure surge or wave caused when a fluid in motion is forced to stop or change direction suddenly (momentum change) is referred to in hydraulics. 0 to 24 - a cohesive soil deposit is considered soft if the unconfined compression strength in kPa. NOVEMBER 2016 4 C° - temperature at which liquid water has the highest density. Pascals - a principle of mechanics that the pressure exerted onto a liquid is transmitted equally and undiminished to all portions of the liquid. Bernoulli - a principle that in any stream flowing steadily without friction the total energy contained is the same at every point in its path of flow. MAY 2017 Porosity - the ratio between the volume of void and the volume of the soil mass. Degree of Saturation - the ratio between the volume of water and the volume of voids. No. 40 - for determining the atterberg limit which is the plastic and liquid limits, the soil sample must pass through 0.425 mm sieve. NOVEMBER 2018 Easy to compact, high shear strength and prone to settlement due to vibrating load are the characteristics of cohesionless soil. In standard penetration tests, medium dense sand has a number of blows of 10 to 30. APRIL 2023 (Bessavilla) The shear strength of a soil increases with increase in normal stress. Triaxial shear test acts on all plane axes except x and y axis.  In what plan is the additional stress (deviator stress) can affect the shear stress? Horizontal Vane Test is a test not performed in a laboratory. In AASHTO, soil greater than 75mm is classified as cobbles. In 1.3cNc + qNq + 0.4BɣNɣ, Nc, Nq and Nɣ are function of angle of friction. When molecules get attracted to others it is called cohesion. Where is the metacenter for stable equilibrium? Above center of gravity. If the volume of voids is equal to the volume of solids, what is the porosity and void equal to respectively? 0.5 and 1.0 The shear strength of a cohesionless soil is proportional to the tangent of the angle of shearing resistance. The intensity of vertical stress at a depth due to a point load acting on the surface of a semi infinite elastic soil mass is directly proportional to the square of depth. When the metacenter of a floating body is lower than the center of gravity, then the body will be in unstable equilibrium. The metacentric height is the distance between the center of the gravity of the floating body and the metacenter. Negative skin friction on piles caused by soft clay, decreases the pile capacity and due to relative settlement of soil. Specific weight of liquid does not vary on any other planet. In civil engineering, soil is a structural material or uncemented aggregate. The weight per unit volume of a liquid at a standard temperature and pressure is called specific weight. PSAD - TERMINOLOGIES MAY 2015 Orthotopic Material - the material composition is the same but its mechanical properties are different in every direction. Homogeneous - materials are the same at all points in the body. Isotropic Material - has a stress-strain relationship that is independent of the orientation of the coordinate system at a point. Elasticity - Refers to the tendency of solid materials to return to their original shape after forces are applied on them. When the forces are removed, the object will return to its initial shape and size. Yielding - refers to the stress at which a material begins to deform plastically.  Work hardening - is the strengthening of a metal by plastic deformation. Buckling - failure by lateral or torsional instability of a structural member, occurring with stresses below the yield of ultimate values. MAY 2016 Toughness - the ability of the material to absorb energy in the plastic range. Resilience - the ability of material to absorb energy in the elastic range. Ductility - refers to the ability of a material to deform in the plastic range without breaking Center of Rigidity - it is the point through which the resultant of the resistance to the applied lateral force acts. Shear Wall - the point on a structure where the resultant vertical force acts. Eccentricity - the distance between the center of mass and center of rigidity. NOVEMBER 2016 Ground Motion or Ground Displacement - it is measured by a seismometer. Inverse Stiffness - refers to the flexibility of a structural system. Yielding - the stress point where a material will have appreciable deform when a small amount of stress is experienced. Toughness - the ability of the material to deform in plastic rance without breaking. Elastic Limit - the greatest stress that can be applied to an elastic body without causing permanent deformation. NOVEMBER 2017 Torsional Shear Stress - the center of mass and center of rigidity of a structure does not coincide; it will develop this kind of stress. Soft Storey - a building which has a floor which is less than 70% as stiff as the floor immediately above it, or less than 80% as stiff as the average stiffness of the three floors above it. Storey Drift - refers to the lateral displacement of one level relative to the other level above or below. MAY 2018 Reciprocal of Deflection - best refer to the rigid structure. Liquefaction is best described as a sudden drop of shear strength. k = k1 + k2 - If two springs with sudden stiffness of k1 and k2 are arranged in parallel. Center of Rigidity - the point through which the resultant of the resistance to the applied lateral force acts.  Center of Mass - the point o a structure through which the applied seismic force acts. Reciprocal of Stiffness - refers to the flexibility of a structure. MSTE - TERMINOLOGIES MAY 2019 Traffic Signs - device mounted on a fixed support whereby a specific message is conveyed by means of words or symbols for the purpose of regulating, warning and guiding traffic. Road Work Signs - warn or advise of temporary hazardous conditions that could endanger road users or the men and equipment engaged on roadwork. Special Instructions Signs - signs that instruct road users to meet certain traffic rule requirements or road condition. Significant Wave - defined as the average height of the highest one third of waves in a wave train. It is the maximum height and wave period of the maximum wave height in wave train. Seiches - are typically caused when strong winds and rapid changes in atmospheric pressure push water from one end of the body of a water to the other. Wind swells - are created by the wind blowing above the ocean close to the shore. Wake effect - the wind speed decreases and the turbulence increases. Wind Sea - when directly generated and affected by local wind. NOVEMBER 2019 A caisson is a watertight structure that is used to carry out construction or repair work in the water, particularly in the construction of bridges, dams, and other large structures. It is a box-like structure made of reinforced concrete or steel that is open at the bottom and closed at the top. Shoring is a temporary support system used in construction to provide temporary structural support to an existing structure or excavation. It is typically used to prevent collapse or instability during construction work, such as excavation, demolition, or renovation of a building. Pier refers to a raised platform or structure that extends out over a body of water, such as a river, harbor, or ocean, and provides a docking point for ships to load and unload cargo or passengers. The sign being described is called a "Guide sign". Guide signs are used to provide information to road users about routes, directions, distances, points of interest, and the  location of services such as gas stations, rest areas, hospitals, and hotels. They are usually placed on highways, expressways, and other major roads to help drivers navigate and plan their trips. Guide signs are typically rectangular in shape and have white lettering on a green or blue background. Traffic instruction sign is a type of traffic sign used to provide information, guidance or instructions to road users. These signs are typically used to indicate speed limits, direction of travel, lane usage, parking regulations, and other traffic regulations. Traffic instruction signs are usually rectangular in shape and are designed with bold, easy-to-read lettering and symbols to convey their message clearly and quickly to drivers. They are an important component of traffic control systems and help to ensure safe and efficient traffic flow. 7 Ways to avoid traffic conflicts: Separating traffic, Traffic signals, Rounabouts, Grade Separations, Speed Limits, Proper signage and markings, Education and Awareness Delay - the difference between the actual time and some ideal travel time for a given segment of a transportation system. Queue Time - refers to the time a vehicle spends waiting in a queue such as in traffic or at a toll booth. Transverse Cracks - cracks approximately at right angles to the pavement of centerline which may be caused by shrinkage or differential thermal stress of the asphalt concrete or may be reflective cracks. Alligator Crack - type of cracking caused by a combination of factors such as aging, poor drainage, heavy traffic loads and inadequate pavement thickness. Block Crack - type of pavement distress that appears as interconnected rectangular cracks resembling a block pattern. It is caused by the shrinkage of the asphalt concrete surface. Longitudinal Crack - cracks that run parallel to the direction of traffic flow or the pavement centerline. Provision of safety sight distance depends on the characteristics of the road environment such as road geometry, road surface conditions, road illumination at night and road topography. Provision of safety distance depends on the characteristics of vehicles such as eye height of the driver and type of vehicles.  Screeding - process of leveling a layer of concrete, mortar or other material with a straight edge of screed board. Trowelling - used in concrete construction to smooth and level the surface of freshly poured concrete. Floating - typically done after the initial screeding process to remove any surface imperfections and consolidate the concrete surface. Finishing - final stage in which the surface of the concrete is treated to achieve the desired appearance, texture and durability. Age of tides - it is the interval which may amount to as much as 2.5 days between the highest tide for each location and new/full moon. Diurnal Tide - tidal pattern characterized by a single high tide and single low tide which last 24 hours and 50 minutes. Lunar Tide - refer to the regular rise and fall of sea levels caused by the gravitational pull of the Moon on the Earth's ocean. Semi-Diurnal Tide - refer to a pattern of tidal fluctuations characterized by two high tides and two low tides approximately equal size in a 24 hour period. Raveling - wearing way of the pavement surface caused by dislodging of aggregate particles and binder. Bleeding - is a form of distress in asphalt pavement characterized by the upward movement of asphalt binder in the pavement surface. Flushing - is the occurrence of a film of asphalt binder on the pavement surface, caused by excessive application of a low viscosity asphalt emulsion or an asphalt binder. Joint Crack Spalling - is the deterioration or breaking of concrete joints or cracks to the effect of traffic loading, temperature changes and freeze-thaw cycles. Batching - is the most important process to prepare concrete. The process of proportioning the cement, water, aggregates and additives prior to mixing concrete. Admixture - is a material added to concrete in addition to cement, water and aggregates during the mixing process. Slump Test - used to determine relative consistency of concrete. Water-Cement Ratio - important factor in determining the strength and durability of concrete. Construction Specifications - written instructions that detail how a facility is to be constructed. APRIL 2023  Hardness - a measure of material's ability to resist indentation or penetration. Consolidation - an increase in soil density of a cohesive soil resulting from the expulsion of water from the soils void spaces. Chronological order of finishing standard weight concrete slabs: Bleeding, Screeding, Leveling, Edging, Jointing, Floating, Troweling and Broom Finishing Elements to consider when planning National Roads: 1. Limited frontage access 2. Development set well back from the highway 3. All access to premises provided via provincial roads 4. Number of intersections to be minimized 5. Suitable at grade-channelized intersections for minor flows and other elements 6. No roadside vendors Health and Safety Committee - given the authority to review reports of inspection, accident investigations and implementation of the program. Grouting - the process of injecting any agent into soil or rock to increase its strength or stability, protect foundations or reduce ground water. Every construction project shall have a suitable Construction Safety and Health Program, which must be in accordance with these rules and other orders and issuances issued by the DOLE. PSAD (Keywords for Problems) Steel Design Bolts ○ Maximum safe load - used least value of P. ○ Required Diameter - used larger value of stress Retaining Wall ○ Minimum thickness - used the larger value ○ Maximum thickness - used least value. Columns ○ Allowable Load - used highest value slenderness ratio or used lowest value of radius of gyration. ○ Moment of Inertia (x axis) - used the distance along y axis ○ Moment of Inertia (y axis) - used the distance along x axis