JPS6335963A - Warm heat curing type slip form device - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention applies to slip form construction methods for variable cross sections or sliding form construction methods for constant cross sections that are widely adopted in the construction of reinforced concrete cylindrical structures (hereinafter referred to as these methods). The sliding formwork equipment (hereinafter referred to as slipform equipment) used in the slipform construction method (hereinafter referred to as slipform construction method) is a heat-cured type that is heated and cured through steel formwork, especially in winter and cold seasons. Regarding slip form construction site.

2. Description of the Related Art In the past, various slip form construction methods, slip form devices, and similar construction methods and devices have been known (for example, Japanese Patent Publication No. 52-19702, Japanese Patent Publication No. 59-337).
No. 48, as described in the Special Publication Sho Go-28911)
.

By the way, in the construction of the slip form method,
The initial compressive strength of concrete required for the frame to slide (sliding) is approximately 0.1 (kg/cm2). The speed of construction depends on how well the work is carried out, which in turn affects the completion of the process and the amount of construction work per day.

However, in the case of slip form construction in the winter when the temperature is low1 For example, when the outside temperature is after 5°Ci'i7I, even if early-strengthening concrete is used, the initial compressive strength of the concrete will be low because the mixing temperature of the concrete is low. 0.
It is a fact that it takes 5 to 6 hours to obtain ffkg/c■2, and the progress of the construction work will not progress at all.

In other words, how quickly the initial strength of concrete can be developed during winter will improve the workability of slip form construction, shorten the construction period, and reduce costs.

■ Conventionally, we focused on the fact that the relationship between curing temperature and curing time has a large effect on the strength development of concrete.
For example, as shown in Fig. 5, the entire outer periphery of the slipform device is surrounded by concrete curing sheets A and B, and a rotary kerosene stove warmer C... The practice is to heat the concrete by setting it up, burning it, and then shaking it around to heat the concrete.

(2) Alternatively, as additionally described in FIG. 5, floodlights D... are installed inside and outside the formwork 4 to mainly heat the formwork 4 for thermal curing.

■ In addition, methods are being implemented to increase the mixing temperature of concrete during the winter. In other words, hot concrete is used as the mixing water to make hot concrete.

In FIG. 5, 1 is a climbing rod, 2 is a hydraulic jack, 3 is a yoke, 4 is a steel formwork supported by the yoke, and 5 is a constructed concrete wall (cylindrical body).

Problems to be Solved by the Invention (I) In the case of curing using jet heaters and sheets as described in (1) above, although it is possible to slightly increase the temperature inside the slipform device, it is not possible to raise the curing temperature of concrete. In particular, the formwork 4 is made of steel.

The temperature of the formwork is the same as the outside temperature, and it is difficult to raise the temperature of the steel formwork 4 even if the temperature inside the curing sheets A and B rises a little. ,
This is because the upper part of the slipform device is structurally open-aired, and warm air is rapidly dissipated upward.

However, in the case of thermal curing method in which hot air from the jet heater C is directly applied to the steel formwork 4, hardening of the concrete is accelerated locally, and although it is possible to increase the initial strength, it causes variations in the strength of the concrete. The formwork 4 cannot be raised until it has a certain level of strength as a whole. Otherwise, the problem of raising the formwork 4 (which may cause local dripping of concrete after being raised) is not possible. be.

([) In the case of thermal curing using a floodlight as described in (2) above, it is difficult to adjust the heat source and heat 1. For example, excessive heating may cause temperature cracks in the concrete. In addition, there is also the problem that the floodlights near the formwork 4 are damaged by concrete that has fallen during concrete pouring.

(m) If hot concrete is used as described in (■) above, equipment and equipment for that purpose are required.

This is often not installed in normal raw kelp tents, and there is a problem in that it costs a lot of money to install a new one.

Means for Solving the Problems As a means for solving the problems of the above-mentioned prior art, a thermal curing type slip form device according to the present invention is provided, examples of which are shown in FIGS. 1 to 4 of the drawings. Street.

In the slipform device, linear heaters 6 are arranged on the outer surface of the steel formwork 4 at approximately equal pitches, and are adhered to the steel formwork 4 with aluminum tape 7, and the heaters 6 are insulated. The structure is such that it is covered with material 8.

Operation When performing slip form construction in winter or cold season, when it is necessary to develop the initial strength of the concrete at an early stage, a heat source is supplied to the heater 6 to heat the steel formwork 4 and increase the strength of the concrete 5. When heat curing is carried out, the steel formwork 4 in contact with the concrete is heated, so the concrete is directly and efficiently cured by heat, and it reliably develops its initial strength in the hard stage. Therefore, the period of sliding of the formwork 4 is shortened, and the construction speed is improved.

In addition, in the case of slipform equipment, in order to make the radius, circumference, wall thickness, and inclination adjustable, parts of the formwork are overlapped so that they can slide over each other, but it is necessary to expand and contract the amount of overlap. In this case, the heater 6 can be attached and detached using aluminum tape 7, and the heat insulating material 8 can be adjusted to ensure adaptability.

Embodiment Next, a preferred embodiment of the invention shown in one drawing will be described.

1 to 4 show the structure of a steel formwork 4 in a slipform device such as that shown in FIG. 5, by way of example.

That is, on the outer surface of a steel formwork 4 with a thickness of about 4 mm, heating wires (hotbed wires) 6 as heaters are meandered in the vertical direction at a pitch of about 30 Illll and arranged evenly over the entire surface, and these are arranged in two upper and lower rows. It is adhered to the steel tA formwork 4 with aluminum tape 7.7.

It should be noted that the heating wire 6 expands and contracts in the lap length 'fA'! in the lap part 9 of the steel formwork 4. An extra length portion 10 having a length that allows for Ii is secured, the extra length portion 10 is made flexible, and is bundled so as not to overlap. In other words, when the wrap length of the wrap portion 9 becomes long, the heating wire 6 as long as the length of the wrap portion 9 is extended from the steel formwork 4 and the extra length lO
When recessing or shortening the wire, take out the heating wire 6 of the required length from the extra length 10 on the exposed outer surface of the steel formwork 4, and attach it with aluminum tape 7. This is how we deal with it.

A foamed polystyrene plate 8 having a thickness of, for example, 50 mm is attached and covered as a heat insulator over the heating wire 6 attached to the outer surface of the steel formwork 4 as described above, to prevent wasteful dissipation of heat generation. ing.

The heating wire 6 is connected to a power source 12 via a temperature controller 11.
is connected to.

Therefore, when constructing the slip form method using a slip form device to which formwork having the above configuration is applied, the steel formwork 4 can be efficiently processed at the temperature set by the temperature controller 11 during winter or cold seasons. By heating the concrete and curing it with heat, the initial compressive strength of the concrete can be reduced to 0. [Ikg/cm7 can be ensured at an early stage to shorten the construction period and reduce costs.

By the way, in order to examine the effect of curing temperature, we compared the cumulative outside temperature and the cumulative temperature of poured concrete for each 4-hour period for 4 days from late February to early March. In the case of 1flT'T(4°CX4
time), whereas in the case of the formwork of the present invention, BIT'
T (15,25°C x 4 hours), and a remarkable curing effect was observed.In other words, the period until the poured concrete develops the specified initial strength is at least 4 hours at outside temperature.
It was confirmed that the average temperature was maintained at 15°C even at 15°C.

Note that the type of heater and its heat source is not limited to the above-mentioned heating wire 6; for example, it is also possible to apply a pipe heater that passes hot water or Z inlet air.

The effects of the present invention are as described in detail in Section 2 together with Examples, and according to the thermal curing type slip form device of the present invention, concrete cast especially in winter and cold seasons can be removed from steel molds. The concrete is heated directly and efficiently and reliably through the frame 4 for thermal curing, thereby increasing the initial strength of the concrete (0.6 kg/slip at the time of slipping).
c+s2) can be expressed early, reliably, and without any irregularities on the whole, so the period of raising the formwork 4 can be shortened, and as a result, the construction period can be significantly shortened and costs can be reduced.

In addition, since the poured concrete is directly heated through the steel formwork 4 in contact with it, thermal loss is small and thermal efficiency is high, so thermal curing can be performed at low cost.

In addition, since the concrete is heated directly through the steel formwork 4, and the temperature during curing can be easily and reliably controlled as the formwork temperature, the concrete can be kept at an appropriate temperature without causing temperature cracks. It is possible to perform thermal curing by adjusting or controlling the temperature to the appropriate temperature according to conditions such as outside temperature, concrete mixing, and mixing temperature, which in turn contributes to the construction of concrete structures of high quality and precision. be.

[Brief explanation of the drawing]

FIG. 1 is a front view showing a part of the formwork applied to the thermally cured slipform device according to the present invention, FIGS. 2 and 3 are a side view and a plan view of the former formwork, and FIG. The figure is an enlarged detailed view of the part (■) in FIG. 3. Figure 5 is an elevational view of the slipform device.

Claims (1)

[Scope of Claims] [1] In a slipform device, its steel formwork (
A heater (6) is installed on the outer side of the frame (4), which is adhered to the steel formwork (4) with aluminum tape (7), and the heater (6) is covered with a heat insulating material (8). A thermal curing type slipform device characterized by: [2] Heater (6) according to claim 1
is arranged in a meandering manner on the outer surface of the steel formwork (4), and the lap part of the steel formwork (4) has an extra length part (10) of a length that allows for expansion and contraction of the amount of wrap. A thermal curing type slipform device characterized by the following: