- What Is An Automatic Level?Answer :A dumpy level, builder's auto level, leveling instrument, or automatic level is an optical instrument used to establish or verify points in the same horizontal plane. It is used in surveying and building with a vertical staff to measure height differences and to transfer, measure and set heights.
- What Is The Use Of Dumpy Level?Answer :A dumpy level is a surveying tool that measures horizontal lines. It is used to determine relative height and distance among different locations. In modern times, it is most commonly used to obtain measurements for buildings rather than to gather information on large tracts of land.
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What Is An Automatic Level and What Is The Use Of Dumpy Level?
Surveying Short Question
Question 1.What Is Surveying?
Answer :
The profession or work of examining and recording the area and features of a piece of land so as to construct a map, plan, or detailed description of it.
Question 2. What Is A Surveyor?
Answer :
Surveyors update boundary lines and prepare sites for construction so that legal disputes are prevented. Surveyors make precise measurements to determine property boundaries. They provide data relevant to the shape and contour of the Earth's surface for engineering, map making, and construction projects.
Question 3. What Is A Property Surveyor?
Answer :
It is important, therefore, that you employ a surveyor yourself to undertake a thorough inspection of the property you wish to buy. The types of surveys available. There are two main types of structural survey available for those buying a property: a Home buyer's Report or a Full Building Survey.
Question 4. What Is A Marine Surveyor?
Answer :
A Marine surveyor (including "Yacht & Small Craft Surveyor", "Hull & Machinery Surveyor" and/or "Cargo Surveyor") is a person who conducts inspections, surveys or examinations of marine vessels to assess, monitor and report on their condition and the products on them, as well as inspects damage caused to both vessels .
What Is A Chartered Quantity Surveyor?
What Is A Chartered Quantity Surveyor?
Members and Fellows of the RICS entitled to use the designation (and a number of variations such as "Chartered Building Surveyor" or "Chartered Quantity Surveyor" or "Chartered Civil Engineering Surveyor" depending on their field .
Members and Fellows of the RICS entitled to use the designation (and a number of variations such as "Chartered Building Surveyor" or "Chartered Quantity Surveyor" or "Chartered Civil Engineering Surveyor" depending on their field .
What Is An Automatic Level?
What Is An Automatic Level?
A dumpy level, builder's auto level, leveling instrument, or automatic level is an optical instrument used to establish or verify points in the same horizontal plane. It is used in surveying and building with a vertical staff to measure height differences and to transfer, measure and set heights.
A dumpy level, builder's auto level, leveling instrument, or automatic level is an optical instrument used to establish or verify points in the same horizontal plane. It is used in surveying and building with a vertical staff to measure height differences and to transfer, measure and set heights.
How to determine the size of elastomeric bearings?
How to determine the size of elastomeric bearings?
For elastomeric bearing, the vertical load is resisted by its compression while shear resistance of the bearing controls the horizontal movements.
The design of elastomeric bearings are based on striking a balance between the provision of sufficient stiffness to resist high compressive force and the flexibility to allow for translation and rotation movement. The cross sectional area is normally determined by the allowable pressure on the bearing support. Sometimes, the plan area of bearings is controlled by the maximum allowable compressive stress arising from the consideration of delamination of elastomer from steel plates. In addition, the size of elastomeric bearings is also influenced by considering the separation between the structure and the edge of bearing which may occur in rotation because tensile stresses deriving from separation may cause delamination. The thickness of bearings is designed based on the limitation of its horizontal stiffness and is controlled by movement requirements. The shear strain should be less than a certain limit to avoid the occurrence of rolling over and fatigue damage. The vertical stiffness of bearings is obtained by inserting sufficient number of steel plates.
For elastomeric bearing, the vertical load is resisted by its compression while shear resistance of the bearing controls the horizontal movements.
The design of elastomeric bearings are based on striking a balance between the provision of sufficient stiffness to resist high compressive force and the flexibility to allow for translation and rotation movement. The cross sectional area is normally determined by the allowable pressure on the bearing support. Sometimes, the plan area of bearings is controlled by the maximum allowable compressive stress arising from the consideration of delamination of elastomer from steel plates. In addition, the size of elastomeric bearings is also influenced by considering the separation between the structure and the edge of bearing which may occur in rotation because tensile stresses deriving from separation may cause delamination. The thickness of bearings is designed based on the limitation of its horizontal stiffness and is controlled by movement requirements. The shear strain should be less than a certain limit to avoid the occurrence of rolling over and fatigue damage. The vertical stiffness of bearings is obtained by inserting sufficient number of steel plates.
What are the advantages of assigning the central pier and the abutment as fixed piers?
What are the advantages of assigning the central pier and the abutment as fixed
piers?
For abutment pier to be assigned as fixed pier while the bridge is quite long, the longitudinal loads due to earthquake are quite large. As the earthquake loads are resisted by fixed piers, the size of fixed piers will be large and massive. In this connection, for better aesthetic appearance, the selection of abutment as fixed piers could accommodate the large size and massiveness of piers. Normally abutments are relatively short in height and for the same horizontal force, the bending moment induced is smaller.
For the central pier to be selected as the fixed pier, the bridge deck is allowed to move starting from the central pier to the end of the bridge. However, if the fixed pier is located at the abutment, the amount of movement to be incorporated in each bearing due to temperature variation, shrinkage, etc. is more than that when the fixed pier is located at central pier. Therefore, the size of movement joints can be reduced significantly.
For abutment pier to be assigned as fixed pier while the bridge is quite long, the longitudinal loads due to earthquake are quite large. As the earthquake loads are resisted by fixed piers, the size of fixed piers will be large and massive. In this connection, for better aesthetic appearance, the selection of abutment as fixed piers could accommodate the large size and massiveness of piers. Normally abutments are relatively short in height and for the same horizontal force, the bending moment induced is smaller.
For the central pier to be selected as the fixed pier, the bridge deck is allowed to move starting from the central pier to the end of the bridge. However, if the fixed pier is located at the abutment, the amount of movement to be incorporated in each bearing due to temperature variation, shrinkage, etc. is more than that when the fixed pier is located at central pier. Therefore, the size of movement joints can be reduced significantly.
In bridge widening projects, the method of stitching is normally employed for connecting existing deck to the new deck. What are the problems associated with this method in terms of shrinkage of concrete?
In bridge widening projects, the method of stitching is normally employed for
connecting existing deck to the new deck. What are the problems associated with this
method in terms of shrinkage of concrete?
In the method of stitching, it is a normal practice to construct the widening part of the bridge at first and let it stay undisturbed for several months. After that, concreting will then be carried out for the stitch between the existing deck and the new deck. In this way, the dead load of the widened part of bridge is supported by itself and loads arising from the newly constructed deck will not be transferred to the existing deck which is not designed to take up these extra loads.
One of the main concerns is the effect of stress induced by shrinkage of newly widened part of the bridge on the existing bridge. To address this problem, the widened part of the bridge is constructed a period of time (say 6-9 months) prior to stitching to the existing bridge so that shrinkage of the new bridge will take place within this period and the effect of shrinkage stress exerted on the new bridge is minimized.
Traffic vibration on the existing bridge causes adverse effect to the freshly placed stitches. To solve this problem, rapid hardening cement is used for the stitching concrete so as to shorten the time of setting of concrete. Moreover, the stitching work is designed to be carried out at nights of least traffic (Saturday night) and the existing bridge may even be closed for several hours (e.g. 6 hours) to let the stitching works to left undisturbed.
Sometimes, longitudinal joints are used in connecting new bridge segments to existing bridges. The main problem associated with this design is the safety concern of vehicles. The change of frictional coefficients of bridge deck and longitudinal joints when vehicles change traffic lanes is very dangerous to the vehicles. Moreover, maintenance of longitudinal joints in bridges is quite difficult.
In the method of stitching, it is a normal practice to construct the widening part of the bridge at first and let it stay undisturbed for several months. After that, concreting will then be carried out for the stitch between the existing deck and the new deck. In this way, the dead load of the widened part of bridge is supported by itself and loads arising from the newly constructed deck will not be transferred to the existing deck which is not designed to take up these extra loads.
One of the main concerns is the effect of stress induced by shrinkage of newly widened part of the bridge on the existing bridge. To address this problem, the widened part of the bridge is constructed a period of time (say 6-9 months) prior to stitching to the existing bridge so that shrinkage of the new bridge will take place within this period and the effect of shrinkage stress exerted on the new bridge is minimized.
Traffic vibration on the existing bridge causes adverse effect to the freshly placed stitches. To solve this problem, rapid hardening cement is used for the stitching concrete so as to shorten the time of setting of concrete. Moreover, the stitching work is designed to be carried out at nights of least traffic (Saturday night) and the existing bridge may even be closed for several hours (e.g. 6 hours) to let the stitching works to left undisturbed.
Sometimes, longitudinal joints are used in connecting new bridge segments to existing bridges. The main problem associated with this design is the safety concern of vehicles. The change of frictional coefficients of bridge deck and longitudinal joints when vehicles change traffic lanes is very dangerous to the vehicles. Moreover, maintenance of longitudinal joints in bridges is quite difficult.
In incremental launching method of bridge construction, what are the measures adopted to enhance sufficient resistance of the superstructure during the launching process?
In incremental launching method of bridge construction, what are the measures
adopted to enhance sufficient resistance of the superstructure during the launching
process?
- During the launching process the leading edge of the superstructure is subject to a large hogging moment. In this connection, steel launching nose typically about 0.6-0.65 times span length is provided at the leading edge to reduce the cantilever moment. Sometimes, instead of using launching nose a tower and stay system are designed which serves the same purpose.
- The superstructure continually experiences alternative sagging and hogging moments during incremental launching. Normally, a central prestress is provided in which the compressive stress at all points of bridge cross section is equal. In this way, it caters for the possible occurrence of tensile stresses in upper and lower part of the cross section when subject to hogging and sagging moment respectively. Later when the whole superstructure is completely launched, continuity prestressing is performed in which the location and design of continuity tendons are based on the bending moments in final completed bridge condition and its provision is supplementary to the central prestress.
- For very long span bridge, temporary piers are provided to limit the cantilever moment.
What is “preset” during installation of bridge bearings?
What is “preset” during installation of bridge bearings?
“Preset” is a method to reduce the size of upper plates of sliding bearings in order to save the material cost. The normal length of a upper bearing plate should be composed of the following components: length of bearing + 2 x irreversible movement + 2 x reversible movement. Initially the bearing is placed at the mid-point of the upper bearing plate without considering the directional effect of irreversible movement. However, as irreversible movement normally takes place at one direction only, the bearing is displaced/presetted a distance of (irreversible movement/2) from the mid-point of bearing in which the length of upper plate length is equal to the length of bearing + irreversible movement + 2 x reversible movement. In this arrangement, the size of upper plate is minimized in which irreversible movement takes place in one direction only and there is no need to include the component of two irreversible movements in the upper plate. Note: “Preset” refers to the displacement of a certain distance of sliding bearings with respect to upper bearing plates during installation of bearings.
“Preset” is a method to reduce the size of upper plates of sliding bearings in order to save the material cost. The normal length of a upper bearing plate should be composed of the following components: length of bearing + 2 x irreversible movement + 2 x reversible movement. Initially the bearing is placed at the mid-point of the upper bearing plate without considering the directional effect of irreversible movement. However, as irreversible movement normally takes place at one direction only, the bearing is displaced/presetted a distance of (irreversible movement/2) from the mid-point of bearing in which the length of upper plate length is equal to the length of bearing + irreversible movement + 2 x reversible movement. In this arrangement, the size of upper plate is minimized in which irreversible movement takes place in one direction only and there is no need to include the component of two irreversible movements in the upper plate. Note: “Preset” refers to the displacement of a certain distance of sliding bearings with respect to upper bearing plates during installation of bearings.
Civil engineering Short Question
What is the purpose of the gap in the road on this bridge?
Purpose of the gap in the road is to allow the road to expand and contract with temperature changes without causing damage or deformation to the road.
What is a projection line?
Projection line is the way, in which the earth is shown on a flat piece of Paper.
What are moment of inertia and its importance in civil engineering?
The moment of inertia measures the opposition any kind of body will have against a certain momentum (along that same axis) trying to rotate that body.
What is the absolute pressure scale?
Absolute pressure is calculated from a vacuum (0 PSI) and atmospheric pressure is14.7PSIa or 14.7 PSI above a vacuum 1PSI on a tire pressure gauge is called 1PSIg = 15.7PSIa 10PSIg=24.7PSIa 100PSIg=114.7PSIa etc.
What is diversion tunnel in a dam?
When a dam is to be built, a diversion tunnel is usually bored through solid rock next to the dam site to byPAss the dam construction site. The dam is built while the river flows through the diversion tunnel.
How do you maintain water pressure?
If you have water pressure and wish to maintain it, do not cause flow in the line, which will reduce pressure due to friction. To keep pressure up, reduce friction by increasing the line size or eliminating some other restriction.
Why does the pressure increase under soil?
Soil pressure increases with depth due to the overburden or self-weight of the soil and due to loads imposed upon the soil.
For example, the pressure variation below the depth of soil is linear and the relation is given by pressure = unit wt * depth. As depth increases, there will be a linear increase in the soil pressure.
For example, the pressure variation below the depth of soil is linear and the relation is given by pressure = unit wt * depth. As depth increases, there will be a linear increase in the soil pressure.
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