Rod Extensometer

Rod Extensometer

Brand : Slope Indicator – USA

Aplikasi :

Rod extensometer digunakan untuk memantau perubahan jarak – pertambahan jarak antara satu angkur atau lebih dalam satu lubang/sumur.

 Tipikal penggunaan :

• Memantau penurunan struktur fondasi.
• Memantau penurunan disekitar atau diatas struktur Tunnel.
• Memantau timbunan pada aktivitas ekskavasi. Sekaligus memantau stabilitas Tunnel atau struktur lainnya.
• Memantau perubahan bentuk pada dinding atau struktur lainnya.

Prinsip operasi :

Komponen Rod Extensometer terdiri dari anchors(angkur), rods with protective tubing(batang dengan pelindung), dan reference head(kepala referensi). Angkur dengan batang yang terpasang dipasang pada lobang pantau. Batang – batang ekstensometer membentang dari angkur pada bagian bawah sampai kepada reference head(kepala referensi), which is installed at the borehole collar. Pengukuran didapat dari “reference head” yang dilengkapi dengan sensor “depth micrometer”, yang digunakan untuk mengukur jarak antara atas dan ujung batang dan permukaan.

A change in this distance, found by comparing the current measurement to the initial measurement, indicates that movement has occurred. Movement may be referenced to a downhole anchor that is installed in stable ground or to the reference head, which can be surveyed. The resulting displacement data can be used to determine the zone, rate, and acceleration of movements, or to calculate strain.

Multipoint Monitoring

The rod extensometer can monitor up to six points along the borehole. The number of monitored points is limited by the size of the borehole, the type of anchor used, the diameter of the rods, and the amount of tubing required for grouting and activating anchors. A two-point extensometer typically requires a 60 mm (2.4 in) borehole; a four-point extensometer requires a 76 mm (3 in) borehole; and a six-point extensometer requires a 96 mm (3.8 in) borehole. Borehole size for packer anchors depends on number of anchors.

Anchors

Two types of anchors are available: the groutable anchor is suitable for rock and the hydraulic anchor is suitable for soils.

Rods

Rods are made of fiberglass or stainless steel. Extensometers using 3/16-inch fiberglass rods can be pre-assembled at the factory, coiled, and shipped to the site, ready for installation. In general, fiberglass rods are easier to install in confined areas, such as tunnels. Fiberglass rods also resist corrosion and are preferred over stainless in alkaline environments. Extensometers using stainless rods must be assembled on site. Stainless rods are stiffer than fiberglass rods of the same diameter and are preferred when compression, rather than extension, is likely, or when longer lengths of rods are required. Protective tubing or protective pipe is installed with the rods to prevent bonding between the rods and grout.

Readout Options

Extensometer measurements can be obtained with a depth micrometer or a sensor. The depth micrometer is suitable when there is easy access to the reference head. However, when access to the reference head is difficult or where real-time or continuous monitoring is required, a sensor is the better option.

PERFORMANCE NOTES
System Accuracy: The main variables in system accuracy are site conditions and the quality of the installation. In general, the best performance is achieved when the borehole is straight and rods are held in tension to keep them straight while the grout backfill cures.
Maximum Recommended Rod Length: In general, rods in tension can be longer than rods in compression, and steel rods can be longer
than fiberglass rods. In non-vertical installations, friction between rods and the protective pipe becomes a limiting factor. The table below suggests maximum lengths for rods in tension and compression.
Number of Monitored Points: The rod extensometer can monitor up to six points. In practice, the number of monitored points is limited by the size of the borehole, the type of anchor used, the diameter of the protective pipe, and the amount of tubing required for activating anchors and grouting. A 76 mm (3″) borehole will accommodate six groutable or hydraulic anchors

Ordering Info :

ANCHORS
Groutable Anchor . . . . . . . . . . . . .51815852
Made from rebar, 19 x 365 mm (0.75 x 14.5″).
Hydraulic Anchor. . . . . . . . . . . . . .51703952
FIBERGLASS RODS
Fiberglass Rod . . . . . . . . . . . . . . . 51815855
Protective Tubing . . . . . . . . . . . . . 51815860
Rod Completion Kit . . . . . . . . . . . 51836240

STAINLESS STEEL RODS
Stainless Steel Rod. . . . . . . . . . . . 51704310
Protective Pipe. . . . . . . . . . . . . . . 51704321
Rod Completion Kit . . . . . . . . . . . 51836210

MECHANICAL REFERENCE HEAD
Single-Point Head . . . . . . . . . . . . 51836110
Multi-Point Head . . . . . . . . . . . . . 51836120
Digital Depth Micrometer . . . . . . 51809620

ELECTRIC REFERENCE HEAD
Single-Point Head . . . . . . . . . . . . 51836130
Multi-Point Head . . . . . . . . . . . . . 51836140
VW Sensor, 60 mm range . . . . . . . 52636305
VW Sensor, 100 mm range . . . . . . 52636325
Potentiometer, 60 mm range . . . . 51836152
Potentiometer, 100 mm range . . . 51836154

SIGNAL CABLE
Signal Cable, 4-Wire . . . . . . . . . . .50613524
For one VW sensor. Not required if 12 wire cable above is used.
Signal Cable, 6-Wire . . . . . . . . . . .53102900
For one potentiometer. Not required if 12 wire cable above is used.
Signal Cable, Multicore. . . . Contact Factory
Universal Terminal Box . . . . . . . . .57711600

INSTALLATION ACCESSORIES
Pipe Adapter . . . . . . . . . . . . . . . . .51835170
Optional adapter for anchoring reference head to 76mm (3″) diameter steel pipe installed at collar
of borehole.
Flange . . . . . . . . . . . . . . . . . . . . . .51836175
Optional adapter for anchoring reference head to concrete pad at borehole collar. 190 mm (7.5″) plastic flange with 152 mm (6″) bolt circle.
Grout Tubing . . . . . . . . . . . . . . . . .50721008
Used to deliver grout from the grout pump to the borehole. 12.7mm OD (0.5″) polyethylene tubing rated for 30 bar (425 psi).
Hydraulic Tubing . . . . . . . . . . . . . .51702701
Used to activate hydraulic anchors. 6.35mm (0.25″) nylon tubing filled with oil.
Hydraulic Anchor Tools . . . . . . . . .51704600
Hydraulic pump with gauge, T-connection, oil volume indicator, 1 gallon of oil, and adapter for filling hydraulic tubing.
Spare Nut & Ferrule. . . . . . . . . . . .51703950
Replacement hardware for connecting hydraulic tubing to anchor.

Catatan : Dalam permintaan penawaran mohon di tentukan untuk panjang Kabel/kedalaman lubang bor/pengamatan (mis : 50mtr(kebanyakan), 100mtr, dll), dan jumlah casing apabila dibutuhkan (panjang casing 3m/buah)

Info :

CP : Yudhistira

Mobile : 08111886845

0818 0816 0634 (WA)

email : naysite2@gmail.com