JPH0623657B2 - How to measure the height of structures under water - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for measuring the height of a structure or a sea bottom under water depth, particularly under deep water depth.

[Prior Art] When constructing a caisson foundation rubble mound, the uppermost layer of the foundation rubble mound on which the caisson is installed reduces the unevenness of the leveling surface and prevents the concentrated load from acting on the bottom of the caisson. (Japanese Patent Application Laid-Open No. 54-70586), Japanese Patent Application Laid-Open No. 56-6827, Japanese Patent Application Laid-Open No. 60-105713) This base surface leveling condition is "leveling accuracy". ± 5 cm, water depth 30
m, averaged area 1,600 m ² ", which is extremely severe. How to install the underwater girder (screed machine) to the level of the foundation surface of the foundation rubble mound (accuracy after compacting rubble stones ± 20 cm), and how to accurately install it at the reference height, in order to secure the leveling surface accuracy. Will be the most important point of. Since the underwater girder is installed independently on the bottom of the sea, it is necessary to have a measuring device that can check the height from the land, but conventional ground leveling equipment has an appropriate measuring device that can check the height from the land. It was not provided.

For example, Japanese Unexamined Patent Publication No. 52-131758 discloses a technique for measuring the water depth by rotating the drum in the forward and reverse directions even when the ship rises and descends due to changes in tide. However, such a known technique does not support the rope with a constant tension but allows the rope to follow the vertical movement of the ship due to the tide level, and therefore cannot be optically accurately measured.

[Problems to be Solved by the Invention] By the way, when the height is checked from the land and the height of the underwater girder is measured from the berth, the problem is that the ship sways due to wind waves. Is a method for accurately measuring the height of an underwater girder irrespective of the motion of a ship due to wind waves, and providing a method of measuring the height of a structure under water.

The present invention is not limited to the measurement of the height of the underwater girder of the base surface leveling facility, but can be carried out for a finished shape inspection of the leveling accuracy of the base surface leveling.

[Means for Solving the Problems] According to the present invention, a string-shaped body is hung on a pulley provided on a support stand erected on a ship, and one end of the string-like body is fixed to a structure or the like under water. , A weight is attached to the other end so that the string-like body always has a constant tension, and a reflective prism that serves as a target is attached to the vertical portion of the string-like body on the water surface, and the string-like body is under water. And a reflection prism are piano wires, and the weight between the reflection prism and the weight is made of stainless wire. By collimating, the height of the reflecting prism is measured, and the height of the structure under the water is measured based on the measured height of the reflecting prism.

[Explanation of Action and Effect] Therefore, first, the piano wire is attached while positioning the pontoon on the structure, and a certain tension is applied to the piano wire by the support stand to absorb the movement due to the sway of the ship and make the reflecting prism stand still. . Then, measure the height of the reflecting prism from land.

As described above, according to the present invention, since the reflection prism is held with a constant tension, the reflection prism is located at a constant height position regardless of the sway of the ship due to the wind wave, and therefore the measurement can be easily performed.

[Embodiment] In FIGS. 1 and 2, a support base 2 is mounted on a barge 1.
Is erected, and a pulley, for example, an aluminum sheave 3 is attached to the support base 2 thereof. One end of a piano wire 5a is connected to an underwater girder (screed machine) 4 on the sea bottom, and the other end of the piano wire 5a is connected to a reflecting prism 6 as a target. Also, stainless wire 5b
Has one end connected to the reflection prism 6, its stainless wire 5b is hung on the pulley 3 of the support base 2, and the other end is connected to a weight, for example, a weight 7 of 60 kg, which is always connected to the piano wire 5a. It brings constant tension. The reflecting prism 6 serving as a target is located on a vertical portion of the piano wire 5a on the sea surface as illustrated. The length of the piano wire 5a is measured when a constant tension is applied. An electronic theodolite and a lightwave rangefinder 8 are set at a base point on land.

In FIG. 1, BL: Bench (point O) KL: Machine point DL: Base surface TL: Target SL: Top of underwater girder HI: Height of underwater girder H: Specific height difference from bench to machine axis l1: Specific height difference from bench to DL h1: Specific height difference with machine axis target l2: Piano wire length h2: Underwater girder bottom surface and DL specific height difference From Fig. 1, l1 + H = h1 + l2 + H1 + h2 Therefore, h2 = l1 + H- h1-l2-H1 Here, l1, l2, H, and H1 are known numbers, and the unknown number is h.
Since it is 1, h2, h2 can be obtained by finding h1.

The reflection prism 6 is collimated by the optical distance meter 8 set at the base point, and the oblique distance d between KL and TL and the vertical angle α are measured,
A specific height difference h1 between KL and TL is obtained.

h1 = dsinα This calculation is automatically processed by the electronic theodolite and h1 is displayed on this display.

The submersible girder installation procedure will be described with reference to FIG. In FIG. 3, 1 is a base leveling boat, 2 is a wire tensioning device (supporting platform), 4 is an underwater girder, 5 is a piano wire, 9 is a leveling machine, 10 is a jack-up leg, and 11 is an extra. A high-wave sounding device is shown.

(1) Hoist the underwater girder from the pontoon using a winch.

(2) After the positioning of the barge is completed, suspend the underwater girder with the underwater girder lifting winch and set it down.

(3) After bottoming the underwater girder, remove the underwater girder lifting wire.

(4) While positioning the ship directly above the underwater girder, attach the piano wires to the four corners of the underwater girder.

(5) A fixed tension (60 kg) is applied to the piano wire on the support base, and the movement caused by the sway of the ship is absorbed by the wire tension device, and the reflecting prism is stopped.

(6) Measure the heights of the four reflecting prisms from land.

(7) Wirelessly report the measurement results to the ship.

(8) Attach the jack-up legs to the four corners of the underwater girder,
Adjust the mound's unevenness and height after the slow bottom with the hydraulic jack operation. After adjustment, mechanically lock with the manual lock mechanism.

(9) The height of the screed machine should be set to 1 even during the base surface leveling work.
Measure every m to understand the deflection of the underwater girder.

INDUSTRIAL APPLICABILITY The measurement system according to the present invention can be used not only for measuring the height of the underwater girder for leveling equipment, but also for performing a quality inspection of the leveling accuracy of the leveling and a quality inspection of the mound surface after truncation.

Fig. 4 shows an example of a finished shape inspection with a leveling accuracy of the base surface.
Wire tensioning device (supporting stand) 2 on the base leveling ship 1.
6 of them are attached, the base surface smoothing surface 13 is dropped to the red wire 14 connected to the stainless wire 5 at a pitch of 5 m, and the height of the base surface smoothing surface is measured. 12 shows a rubble mound.

[Effects of the Invention] As described above, the present invention has the following excellent effects.

(I) Since the height of the reflecting prism provided on the ship from land is optically measured, the measurement result is accurate.

(Ii) Accurate measurement is possible because the reflection prism installed on board is not affected by wind waves.

(Iii) Since the piano wire and the stainless steel wire are thin and durable, it is easy to hold the reflecting prism and does not interfere with light.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a method of measuring the height of a structure under water according to the present invention, FIG. 2 is a detailed view of a supporting frame portion of FIG. 1, and FIG. FIG. 4 is a diagram showing a mode of measuring the height of the underwater girder of the equipment, and FIG. 4 is a diagram showing a mode of inspecting a finished form with a leveling precision of a base surface leveling according to the present invention. 1 ... Boat, 2 ... Supporting platform, 3 ... Aluminum sheave, 4
...... Underwater girder, 5a ...... Piano wire, 5b ...... Stainless wire, 6 ...... Reflecting prism, 7 ...... Weight, 8 ...... Light wave range finder

Claims (1)

[Claims] 1. A cord-like body, in which a string-shaped body is hung on a pulley provided on a support stand erected on a ship, one end of which is fixed to a structure under water and a weight is attached to the other end. A constant amount of tension is always applied to, and a reflective prism that serves as a target is attached to the vertical portion of the string-like body above the water surface.The string-like body is a piano wire between the structure under water and the reflecting prism, When measuring the height of a structure under water, in which the space between the prism and the weight is made of stainless steel wire, collimate the reflecting prism with an optical distance meter installed at the base point on land, and measure the height of the reflecting prism. A method for measuring the height of a structure, etc. under the water, which comprises measuring and measuring the height of the structure, etc. under the water based on the measured height of the reflecting prism.