JPH0452808B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a top measuring device during concrete placement in a continuous underground wall construction method.

Conventional technology In the continuous underground wall construction method, concrete is poured between trench walls filled with muddy water, so it is difficult to grasp the top position of the concrete, and we have experience in construction management such as adjusting the amount of concrete poured. I had no choice but to rely on my intuition.

Problems to be Solved by this Invention Therefore, this invention aims to solve the problems of concrete using a continuous underground wall construction method, which enables accurate grasping of the top position of concrete, rational construction management such as concrete placement amount and muddy water management, and good work efficiency. The purpose of this invention is to provide a pouring top measuring device.

Structure of the Invention The concrete pouring top measuring device for continuous underground wall construction according to the present invention uses a cable/wire winding device installed at the upper end of the trench wall opening to lift the casing in muddy water and unsolidified concrete using a hanging wire. A plurality of pressure sensors connected to the cable from the cable/wire winding device are installed at predetermined intervals in the longitudinal direction of the casing, and the detected values of these pressure sensors and wire feeding are Equipped with a control unit that calculates and displays the pressure gradient in the longitudinal direction of the casing by inputting the length, and determines the top of concrete pouring, which is the interface between concrete and muddy water, from the difference in pressure gradient with respect to depth between muddy water and concrete. It is characterized by the point it is configured to measure.

Embodiments The present invention will be explained below with reference to illustrated embodiments. FIG. 1 is a perspective view showing the overall view of the embodiment, in which a cable/wire winding device 7 is installed on a guide wall 2 formed at the upper end of the opening of the groove wall 1. .

This cable/wire winding device 7 allows the hanging wire 8 and the cable 9 to be wound up by paying out the hanging wire 8 and the cable 9 from a drum which is rotatably operated by a suitable drive mechanism (not shown). A cylindrical casing 10 is suspended from the tip of the hanging wire 8, and when the hanging wire 8 is paid out and wound up by the cable/wire winding device 7, muddy water 5 and concrete 6 before hardening are removed.
The inside can be raised and lowered freely. As shown in FIGS. 1 and 2, this casing 10 has four pressure gauges arranged at predetermined intervals in the longitudinal direction of the cylindrical casing 10.
PG1-4 are installed. Pressure gauge PG1~4
The strain gauge type pressure transducer 13 is attached to the mounting flange 12.
are connected to the cables 9, and are capable of detecting the pressure at each point in the depth direction of the muddy water 5 and the concrete 6 where the casing 10 is located. Further, a vibrating body 11 is attached to the lower end of the casing 10 and is configured to vibrate by being supplied with power from a cable 9', so that it can easily penetrate into the concrete 6.

A calculation indicator 3 is arranged near the cable/wire winding device 7 on the ground, and a length measuring device (not shown in the figure) of the hanging wire 8 consisting of a pulse generator, etc. provided in the cable/wire winding device 7 is installed. The configuration is such that length measurement (depth) signals from the pressure gauges PG1 to PG4 are inputted via the cable 9. The calculation indicator 3 can calculate and indicate the pressure gradient at the depth at which the casing 10 suspended between the groove walls 1 and 1 is suspended from these input data.

In the above configuration, when measuring the top of concrete placement with this measuring device, the hanging wire 8 is let out from the cable/wire winding device 7, and the measured values P1 to 4 of the four pressure gauges PG1 to PG4 are separately measured. Pressure gradient characteristics are calculated from the input depth data.

Here, if the casing 10 is located in muddy water 5, the characteristic diagram will be as shown in FIG. 3a, and if it is located in concrete 6, the characteristic diagram will be as shown in FIG. a,
It is possible to determine which state b.

Therefore, the measured values of the four pressure gauges PG1 to PG4 are compared simultaneously, and the pressure gradient α1 due to the measured values P1, 2 of the upper two pressure gauges PG1, 2 and the pressure gradient α1 of the lower two pressure gauges PG1, 3 are calculated. By comparing the absolute values of the slope α2 of the measured values P3 and 4, the pressure gauge PG2 is determined as shown in Figure 3b.
The cable/wire winding device 7 is used to wind the casing 10 so that the intersection point of the slope (the casting surface) is between the casing 10 and the PG3.
Manipulate position.

Perform these casing position operations while observing the output of the calculation indicator 3, and calculate 1-2 from 1 obtained from the payout length of the hanging wire 8 and the length of the casing 10 and the calculated value 2 of the calculation indicator 3, and then calculate the concrete Measure the pouring surface.

Here, the calculation indicator 3 displays the measured values P1 to 4 of each pressure gauge PG1 to PG2 and the casing tip depth in digital values or directly displays a characteristic graph.
It can also be a CRT type.

Effects of the Invention The embodiment of the concrete pouring crest measuring device for the continuous underground wall construction method according to the present invention is as described above, and the following effects can be mentioned.

In the continuous underground wall construction method, the concrete top position can be accurately grasped, and construction management such as the amount of concrete placed and muddy water management can be performed rationally and with good work efficiency.

[Brief explanation of the drawing]

FIG. 1 is a cutaway perspective view showing an embodiment of the present invention;
Figure 2 is an enlarged view of the casing, Figure 3 a, b, c
is a pressure gradient characteristic diagram according to the casing position with respect to muddy water and concrete. DESCRIPTION OF SYMBOLS 1...Groove wall, 2...Guide wall, 3...Calculating indicator, 4...Reinforcing bar, 5...Muddy water, 6...Concrete, 7...Cable wire winding device, 8...
... Hanging wire, 9, 9'... Cable, 10... Casing, 11... Vibrating body, 12... Mounting flange, 13... Pressure transducer, PG1-4... Pressure gauge.

Claims (1)

[Claims] 1. A cable/wire winding device that is installed at the upper end of the groove wall opening and is capable of letting out and winding up cables and hanging wires to arbitrary lengths; A casing that is suspended from the tip of a hanging wire that can be moved up and down through the muddy water between the trench walls and concrete before solidification, and is equipped with a plurality of pressure sensors connected to the cable at predetermined intervals in the longitudinal direction. and a control unit connected to the other end of the cable of the cable/wire winding device to calculate and display the pressure gradient in the longitudinal direction of the casing from the hanging wire payout length and the detected value of each pressure sensor. Concrete pouring top measuring device.