By precision

by structure

Set up instruments

rough leveling

Adjust the three foot screws to center the circular level bubble, which is called rough leveling

Focus and aim

Precise leveling

reading

By precision

Dial scale and reading method

Angle measurement: horizontal angle measurement and vertical angle measurement

Low precision measurement: sight distance measurement

centering

Leveling

Sight

reading

Large scale: 1: 500, 1: 1000, 1: 2000, 1: 5000, 1: 10000 [ten thousand]

Medium scale: 1: 25,000, 1: 50,000, 1: 100,000 [one hundred thousand]

Small scale: 1: 250000, 1: 500000, 1: 1000000 [millions]

right angle intersection method

polar coordinate method

angle intersection method

distance intersection method

Leveling method: parts where the error is required to be no more than ±10mm

Photoelectric ranging trigonometric elevation method

Analytical Trigonometric Elevation Method

sight distance method

When using a theodolite instead of a level for engineering stakeout, the distance between the stakeout point and the elevation control point must not be greater than 50m.

Original topographic map and original section map measurement of the excavation area

Excavation contour point stakeout

Excavation completed topography, cross-section measurement and engineering quantity calculation

case point

Instructions

Distance measurement can be performed according to conditions and accuracy requirements

Drawing selection

Scale selection

In the calculation of excavation engineering quantities, the area calculation method can be analytical method or graphical method (integrator).

When the difference between two independent measurements of the excavation work volume in the same area is less than 5% (rock) and 7% (earthwork), the middle value can be taken as the final value.

Measure and set the molding or filling outline points of various buildings

Check the shape and position of erected formwork and prefabricated (embedded) parts

Calculate the amount of filling work

The difference between the setting out and checking points should not be greater than 1.4m (m is the error in the measurement and setting out of the contour points)

Calculate selection

The amount of earth and stone filling should be calculated based on the actual measured dividing lines of various filling materials.

If the difference between two independent measurements of the same project is less than 3% of the volume, the middle value can be taken as the final value.

Landslide observation in construction areas

High slope excavation stability monitoring

Observation of Horizontal Displacement and Subsidence of Cofferdam

Temporary foundation settlement (rebound) and crack monitoring

The accuracy of the base point for deformation observation shall not be less than four decimal places.

The base point must be established on stable bedrock outside the deformation zone.

At least one group of base points for vertical displacement must be laid out, with each group having no less than three fixed points.

The measuring point should be firmly combined with the deformation body.

Landslide measuring points should be located in the axis direction with large sliding amount and fast sliding speed and in the landslide front area.

Observation points for cracks in mountains or buildings should be buried on both sides of the crack.

Landslide and high slope stability monitoring adopts intersection method

Horizontal displacement monitoring adopts sight line method (movable target method and small angle method)

For vertical displacement observation (settlement observation), the horizontal observation method should be used.

During the filling process of core wall, sloping wall and dam shell of earth and stone dam, every second layer of materials must be measured and the edge line measured and drawn into a chart for reference upon completion.

human reasons;

The reason for the instrument;

The influence of external environment.

System error: changes according to certain rules;

Accidental error: no regular changes;

Gross error: Carelessness or interference.

inclined structure

fold structure

fault structure

relaxation crack

Creep

collapse

landslide

Set a reasonable slope

Slope protection

Foundation pit support

lower water table

Purpose

method

The reservoir dam is a level 2 or level 3 permanent hydraulic structure according to the above regulations. If the dam height exceeds the index in the table below, its level can be raised by one level.

The barrage gate is rated as Level 2 and Level 3 according to the table. When the verified flood flow through the gate is greater than 5000m^3/s and 1000m^3/s respectively, the building level can be raised by one level.

Flood standards cannot be raised

The level of permanent hydraulic structures of flood diversion channels (channels), flood diversion and flood control gates should be no lower than the level of permanent hydraulic structures of the embankments where they are located.

Air-hardening cementitious materials

Hydraulic cementitious materials

metallic material

Asphalt materials, plant materials and synthetic polymer materials

Earth materials, sand and gravel, asbestos, wood, etc. and their simply collected and processed finished products

Lime, cement, asphalt, metal materials, geosynthetic materials, high molecular polymers

The soil materials of homogeneous earth dams are sandy clay and loam, and their permeability coefficient should not be greater than 1×10 ^-4cm/s

Clay, sandy loam, loam, clay soil and other materials

Blocks, gravel, and pebbles can be used, but weathered rocks are not suitable.

For external concrete in areas where water levels change and for concrete on overflow surfaces washed by water flow, Portland cement, ordinary Portland cement, and Portland dam cement should be given priority, and pozzolanic Portland cement should be avoided.

For concrete with frost resistance requirements, Portland cement, ordinary Portland cement, and Portland dam cement should be used first, and air-entraining agents or plasticizers should be added to improve the frost resistance of the concrete. When environmental water and sulfate attack occur, sulfate-resistant Portland cement should be preferred.

No cement

For concrete inside large-volume buildings, priority should be given to slag Portland dam cement, slag Portland cement, fly ash Portland cement, pozzolanic Portland cement, etc. to meet the requirements of low thermal properties.

For concrete located in water and underground, slag Portland cement, fly ash Portland cement, pozzolanic Portland cement, etc. should be used.

With cement

Manufacturer's factory quality certificate

28d strength certificate

Those who have any of the following circumstances should be retested and used according to the retest results

Commonly used to express sinking degree. The sinking degree is the depth to which the standard cone sinks in the mortar.

Water retention can be expressed by the bleeding rate, and the degree of stratification is an indicator that is often used in engineering.

Mortar with a degree of delamination greater than 2cm is prone to bleeding and should not be used. Therefore, the delamination degree of the mortar is preferably 1 to 2cm.

Plasma-to-bone ratio (W)

Water to cement ratio (W/C)

sand rate

Workability

strength

Durability

Concrete requirements for different parts

Fine aggregate of concrete: aggregate with a particle size between 0.16 and 5mm.

Coarse aggregate for concrete: Aggregate with a particle size greater than 5 mm.

Admixtures that improve the workability of concrete, including water reducing agents, air entraining agents, and pumping agents

Admixtures that adjust the setting time and hardening properties of concrete include accelerating agents, early strength agents, and retarders.

Admixtures that improve the durability of concrete include air-entraining agents, waterproofing agents, rust inhibitors, curing agents, etc.

1) Quality testing and control of raw materials

2) Detection and control of mixed concrete quality

3) Concrete detection and control during pouring

4) Detection of hardened concrete

5) Concrete construction quality assessment

Hot rolled plain round steel bar

Hot rolled ribbed steel bars

Cold drawn and hot rolled steel bars

Cold rolled ribbed steel bars

Waste heat treatment steel bars

Cold rolled twisted steel bar

steel wire

index

Mechanical properties

Have a factory quality certificate or test report, and each bundle (coil) of steel bars should be hung with a sign. The sign should be marked with the manufacturer, production date, brand, product batch number, specification, size, etc.

During the inspection, 60 tons of steel bars of the same furnace (batch) number and the same specification and size are considered as one batch. Randomly select 2 steel bars that have passed external quality inspection and diameter measurement, and take a tensile test piece and a cold bending test piece from each for inspection. Two or more test pieces for the same purpose are not allowed to be taken from the same steel bar. When sampling steel bars, the ends of the steel bars must be cut off by 500mm before taking samples. The tensile inspection items include three indicators: yield point, tensile strength and elongation. If any of the indicators does not meet the regulations, the tensile inspection item is deemed to be unqualified. There should be no cracks, peeling or breaks in the cold-bent specimen after bending.

Reinforcing steel bars with unknown steel numbers must be inspected and passed before they can be used. The number of test pieces taken during inspection shall not be less than 6 groups

Steel fibers of the same variety and specifications used in the same project shall be counted as one inspection batch for every 20t, and any less than 20t shall be counted as one inspection batch. Different batches or non-continuous supply of steel fibers that are less than one inspection lot shall be treated as one inspection lot.

The steel fiber sampling inspection items should include: fiber appearance, size, tensile strength, bending performance and impurity content.

Synthetic fibers of the same variety and specifications used in the same project shall be counted as one inspection batch for every 10 tons, and if less than 10 tons are used, one inspection batch shall be counted. Different batches or non-continuous supply of synthetic fibers that are less than one inspection lot shall be treated as one inspection lot.

The sampling inspection items for synthetic fibers should include: fiber appearance, size, breaking strength, initial modulus, elongation at break and alkali resistance.

The segregation and bleeding inspection of the hydraulic fiber concrete mixture should be sampled at the pouring site, and should be no less than 2 times per shift.

The quality inspection of hydraulic fiber concrete is mainly based on the compressive strength of the design age; the normal fiber concrete is based on the compressive strength of the 150mm cube specimen under standard curing conditions, and the sprayed fiber concrete is based on the compressive strength of the large plate specimen that has completed standard curing. The processed 100mm cube shall prevail. The sampling of hydraulic fiber concrete specimens is mainly done at the machine mouth. Each group of concrete specimens should be sampled and produced in the same storage hopper or transport compartment.

Soil particle shape, size, uneven coefficient and water temperature

Empirical method, indoor measurement method, field measurement method

K=(QL)/(AH)

The fine particles in non-cohesive soil move along the pore channels between coarse particles or are taken out by seepage, causing the formation of pores in the soil layer and the generation of concentrated water inrush.

Piping first starts from the seepage escape point and then gradually develops upstream. The hydraulic slope when individual fine particles in the soil begin to move within the pores under the action of seepage is called critical slope.

The phenomenon of simultaneous movement of particle groups in non-cohesive soil

Phenomenons such as uplift, fracture and floating of clay soil occur

The phenomenon of flowing soil mainly occurs at the seepage outlet of clay soil and relatively uniform non-cohesive soil.

Usually only used in rock masses

Set up horizontal and vertical anti-seepage bodies to increase the length of the seepage path, reduce the seepage slope or intercept the seepage flow

Set up drainage ditches or pressure relief wells to reduce the seepage pressure at the downstream seepage opening, and eliminate seepage water in a planned manner

For areas where piping is likely to occur, a filter layer should be laid to intercept fine particles that may be carried away by seepage.

For areas where flow soil is likely to occur, the cover weight at the seepage outlet should be increased. A reverse filter layer should also be laid between the cover weight and the protective layer.

The most reliable method is to build a seepage-proof wall in the permeable soil layer

Prevent the protected soil from seepage and deformation

The permeability is greater than that of the protected soil, and the seepage water can be discharged smoothly.

Will not be blocked by fine-grained soil and fail

Constant flow: water flow that does not change over time

Unsteady flow: water flow that changes with time

Uniform flow: The streamlines of water flow are straight lines parallel to each other.

Non-uniform flow: The streamlines of the water flow are not parallel straight lines.

Laminar flow: The liquid particles in each flow layer move in an orderly manner without mixing with each other.

Turbulent flow: The liquid particles in each flow layer form vortices and mix with each other during the flow process.

Rapid flow: When the water flow encounters an obstacle, it only causes local changes in the water surface, and this change does not propagate upstream.

Slow flow: When the water flow encounters an obstacle, the interference of the obstacle on the water flow can be propagated upstream.

It mainly relies on the strong turbulence, shearing and mixing between the surface roll generated by hydraulic jump and the bottom mainstream Mostly used in drainage buildings with low water head, large flow rate and poor geological conditions. Water gates basically adopt this energy dissipation method.

Also known as the nose bridge, there are two types: continuous type and differential type. Suitable for high and medium dams on hard rock foundations

Use the nose ridge to lift the mainstream of the high-speed water flow to the downstream water surface The high-velocity mainstream is located on the surface It is suitable for medium and low head projects where the tail water is deep, the flow rate changes range is small, the water level changes is small, or there are requirements for ice removal and drifting wood. Generally no need for protection

It is suitable for situations where the tail water is deep, the flow rate change range is small, the water level changes is small, or there are requirements for ice and driftwood removal. Generally no need for protection

Use the water cushion formed by the downstream water depth to consume water flow energy

The water jets from both sides create a collision in the air, consuming energy.