1. Saudi Electricity Company
Distribution Services Sector
CONSTRUCTION STANDARD FOR
UNDERGROUND DISTRIBUTION NETWORK
PART 17: CABLE TRENCHES
Issue Date: 8/2019 Page: 1 of 45
SDCS-02-17 REV.01
SDCS-02-17
Rev.01
CONSTRUCTION STANDARD FOR UNDERGROUND
DISTRIBUTION NETWORK
PART 17: CABLE TRENCHES
This document contains proprietary information developed by and for exclusive use of Saudi Electricity
Company (SEC) Distribution Network. Your acceptance of the document is an acknowledgment that it
must be used for the identified purpose/application and during the period indicated. It cannot be used or
copied for any other purposes nor released to others without prior written authorization of SEC
Distribution Sector. SEC shall assume no responsibility for any type of misuse and/or misapplication,
and any arm resulting there from. SEC also reserves the right take any necessary actions to protect its
interest against unauthorized use.
2. Saudi Electricity Company
Distribution Services Sector
CONSTRUCTION STANDARD FOR
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PART 17: CABLE TRENCHES
Issue Date: 8/2019 Page: 2 of 45
SDCS-02-17 REV.01
SDCS-02-17
Rev.01
CONSTRUCTION STANDARD FOR UNDERGROUND
DISTRIBUTION NETWORK
PART 17: CABLE TRENCHES
3. Saudi Electricity Company
Distribution Services Sector
CONSTRUCTION STANDARD FOR
UNDERGROUND DISTRIBUTION NETWORK
PART 17: CABLE TRENCHES
Issue Date: 8/2019 Page: 3 of 45
SDCS-02-17 REV.01
Table of Contents
1 INTRODUCTION .............................................................................................................4
2 SERVICE CONDITIONS AND CONSTRUCTION PARAMETERS ............................4
3 REVISION AND ADDITIONS ........................................................................................4
4 DEFINITIONS...................................................................................................................4
5 RIGHT-OF-WAY..............................................................................................................4
6 DIRECT BURIED CABLE INSTALLATION.................................................................5
7 SOIL CLASSIFICATION: ..............................................................................................15
8 SOIL AND ASPHAILT TEST........................................................................................16
9 Specification of Installation of Duct Bank at Road Crossing..........................................21
9.1 General:...................................................................................................................21
9.2 Excavation: .............................................................................................................21
9.3 Duct Bank construction ...................................................................................... 22
9.4 Backfilling and reinstatement............................................................................. 23
9.5 Duct cleaning and inspection .............................................................................. 23
9.6 Concrete Specification ....................................................................................... 24
10 General notes on Medium voltage HDD works...............................................................25
4. Saudi Electricity Company
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CONSTRUCTION STANDARD FOR
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PART 17: CABLE TRENCHES
Issue Date: 8/2019 Page: 4 of 45
SDCS-02-17 REV.01
1 INTRODUCTION
This standard specifies the design, and installation practices to be applied in the
construction of MV and LV cable of underground distribution system. It is intended to
assist the engineers and field personnel to achieve standardization in construction and to
ensure a satisfactory and economical level of service without operating restrictions so
that the operational errors should be minimum for safety and reliability.
2 SERVICE CONDITIONS AND CONSTRUCTION
PARAMETERS
For construction and operation of underground cable distribution network, the service
conditions and system requirements shall be as given in the latest revision of SEC
General Specification No.01-SDMS-01.
3 REVISION AND ADDITIONS
This standard is subject to revision as new materials and methods of construction are
developed. The latest revision of this standard shall be applicable. Revised sheets shall
be issued from time to time and should be inserted as soon as these are received.
Superseded or obsolete sheets shall be removed immediately upon receipt of revised
sheets. The date of the latest issue of each sheet is printed at the top corner under the
standard number.
4 DEFINITIONS
Ultimate strength is the maximum load which a material will sustain when the load is
gradually increased until the rupture or failure takes place.
5 RIGHT-OF-WAY
If required by the local authority, the right-of-way (R-O-W) for the proposed route of an
underground cable must be obtained from the concerned authority-
(e.g. municipality, ministry of communication) during engineering stage of the project.
Given below is the procedure to be followed in obtaining R-O-W:
a. Prepare R-O-W drawing proposed showing proposed route of the underground
cable, cross-section of the trench or duct bank (if required) and location of other
utilities (e.g. telephone, water, sewer) lines along proposed route (if known).
b. Submit R-O-W drawing to the relations section in the concerned operating area.
c. The actual construction work shall not be started until the digging permit from
relevant authorities is obtained.
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SDCS-02-17 REV.01
Note: Being the most economical way, direct earth buried cable laying has been
standardized except where the cable route intersects road, street and other utility mains.
The major activities associated with direct buried cable installation are trench excavation,
cable laying, are described in the following sections. through is trench constructions for
direct buried cable.
6.4 Trench Excavation
Before proceeding with actual work of trench excavation, following preparations should
be completed:
a. Review the cable route drawings, R-O-W drawings, digging permit, and inspect
the cable route from end to end.
b. Decide locating where cable drums shall be unloaded at site, keeping in view the
actual cable lengths on drums.
c. Decide locations of cable joints. Avoid street intersections. Joints should
preferably be made no closer than 10 meters from edge of any street
intersections.
d. Obtain necessary permissions from the traffic police for the work schedule,
warning and lights and design of detours.
e. Keep ready the necessary number of night warning lamps, stands, wooden/steel
bridges for maintaining pedestrian
f. Arrange necessary manpower keeping in view the work schedule and expiry date
of digging permit.
6.4.1 Trench Specification
الحفريات مواصفات:-
1.ينبغيأبالكابالت الحفريات تكون نواإل قدر مستقيمة المواسيرأ و مكانو فقيةو عموديةتحويل وجود حالة في
يجبأبتدرج يكون نالمواصفات حسببا الخاصة.للضرر الكابل لتعرض منعا لكابالت
2.يجب الحفرياتأتمدد نإ( لى111مليمالكي تحت من ) تريقل ما على للسماح الماسورة أو بلمن(111مليمتر)
منو حول الناعم الرمل. الكابل تحت
3.( بعمق تكون ان يجب الحفريات651مليمتر( و المنخفض الضغط كابالت لحفريات )811مليمترلحفريات )
و المتوسط الضغط كابالتيجب العمق هذا عن زيادة الحفر حالة فيأالردم إعادة تتم نإالعمق لىبمواد المطلوب
د ( بنسبة مختارة55حسب ) %ASDM( على المحتوية للتربة15# ( رقم المنخل من ) مار %211(أو
(85( أقل على المحتوية الصرف لحرية المستخدمة الصقة الغير للتربة نسبية كثافة ) %15الغير للمادة ) %
الترب بالستيكيةة# ( رقم المنخل من المارة211.)
4.األيجب الحفرية في الضعيفة أو اللينة جزاءأأو سبق ما حسب تد نأبموا الضعيفة التربة تغيير يتم نردم د
مختارةالمواصفات حسب جيدة.
5.يكون أن يجب الحفرية أسفلمتساويوو الصخور من خالالحادة الموادالتيبالكابل تضر أن يمكن.
6.الحفرية عرضالمتوسط الجهد لكابالت العادية(411مليملكي ) ترو واحد بلعرض(611مليمتر)و للكابلين(
511مليمتر)و كابالت لثالثيتمإضافة(311مليمتر)كي لكلإضافي بل.
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CONSTRUCTION STANDARD FOR
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SDCS-02-17 REV.01
جدول2:.الحفريات لتدعيم القياسات
7.يجبأ( عمقها يبلغ التي الخنادق في تستعمل ن1.2)مترأ( األقل على تمتد ساللم أكثر و1.51سطح فوق )متر
في الساللم هذه توضع ان ويجب .الخندقأيزي ال بحيث ماكند( االخر عن السلم بعد7.6)متر.
8.المستعرضة الركائزأ:يجب الخندق رافعات و
a.أوضعية في توضع نأ.صحيحة فقية
b.أعمودية فراغات بينها تتر ن
c.أبربطا (تربط بإحكام تثبت نتنزلق ال بحيث )تأ.تسقط و
5.صناديق استخدام يمكنالخنادقالمتنقلةأوأغطيةالخنادقاالنزالقيةبدالمنتدعيمالجوانبوعند ،إمالتها أو
و تصمم ان يجب استعمالهاو تنشاتصانبحيثتوفرمنالحمايةالالزمةلذلكالخندقماهوأو معادلأمما فضل
أ باأللواح التغطية توفرهوالجوانب تدعيم.
11.يجبأالردم يسير نوإزالةدعاماتالخندقمعبعضهماويتمالعملمنقاعالخندقإلىأعلىوالرافعات تحرر
واأل.ببطء كتاف
مالحظة:
الصلبة الصخور من الجوانب تدعيم يلزم الأالبركانية الصخور وأالصلصال من المشكلة الصخور وأاستبدال يمكن و
الخشببالركائزالفوالالمستعرضة ذيةوالركائزذاتالمقاومةحسب المعادلةالرغبة.
6.4.3 Sand Bedding/Cover and Cable Tiles
A bedding of Clean, fine sand shall be placed at the bottom of the trench. After laying
the cable, all stone and rubble that have fallen in to the trench during the cable laying
shall be removed. A cover of clean, fine sand shall be placed over the cable. The
thickness of sand bedding/cover shall be as per the relevant trench construction drawing.
The sand bedding and cover shall be spread by hand tools to maintain an even thickness.
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الناع الرملم:
يتم( بسمك الكابل وحول أسفل ناعم رمل وضع111مليمترللمواصفات مطابقا الرمل ويكون الكابل وأعلى أسفل )اآلتية:
مقاسحجم:المنخل
جدول3.المنخل مقاسات :
بلكالحماية:
يجبحمايةالكابالتالمطمورةللجهود٣٣.فوذلكالرئيسة المحطات بين الربط عندفقطبواسطةبلكالحمايةمقاس
51* مم211* مم411يتم و مموضعهفوقرملالحماية.
6.4.4 Backfilling and Reinstatement
Backfilling and reinstatement of the trench shall be in accordance with the requirements
of the authority (e.g. municipality. MOC, etc.) under whose jurisdiction the area falls.
Warning tapes shall be laid in the backfill.
والدك الردم:
1.يتموزارة أو والقروية البلدية الشئون وزارة مواصفات حسب مختارة بمواد ردمها المطلوب األماكن في الردم
و المواصالتاإلخالل عدم معه في ورد بماذ.المواصفات ه
2.( من أكثر بعمق الطبقات في611مليمترسمكها يزيد ال بحيث طبقات علي الردم يتم ،األساس تحت ما طبقة من )
عن(311مليمترأقصى كحد )وو بالماء ترش أن يجبالنسب حسب الحفرية في توضع أن قبل ًاجيد تخلط
للوصول المقررةإلىبموجب كثافة أحسنو المعدلة برمتو تجربةللوصول تهرسإلى( نسبة51الكثافة من ) %
ال العظمى الجافةالمعدلة بركتو تجربة بموجب مقررة.
3.الط فيعلى أعاله الطبقات تلي التي بقات( من أقل عمق611مليمترعلى فتردم األساس تحت من )،ًاأيض طبقات
و( عن يزيد ال طبقة كل سمك211مليمترو )يجبو بالماء ترش أنحتى تهرسإلى الوصول(55من ) %
و ، العظمى الجافة الكثافة.للمواصفات ًاطبق المواد تكون أن يجب
4.و الصخور قطع أو المكسرة الحصمة من متجانس مخلوط من تتكون المتدرج الحجري األساس تحت ما طبقة
و الرملو ،الطمي:اآلتي حسب الطبقة هذه مواد تدرج أن يجب
14. Saudi Electricity Company
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CONSTRUCTION STANDARD FOR
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PART 17: CABLE TRENCHES
Issue Date: 8/2019 Page: 14 of 45
SDCS-02-17 REV.01
6.4.5 Concrete:
:كاآلتي الواحد المكعب للمتر الخرسانة خلطات تتكون
1.( العادية الخرسانة811مليمتر2
بحصى،متدرج411مليمتر2
،نظيف رمل251أسمنت كجم.)
2.( المسلحة الخرسانة811مليمتر2
بحصى،متدرج411مليمتر2
،نظيف رمل351أسمنت كجم.)
3.الحص من عينات تقديمىو.المشرف المهندس قبل من لالعتماد الرمل
1. All concrete surfaces in contact with ground shall be provided with two (2) layers of
polyethylene vapor barrier / Each layer shall be six (6) Mil Thickness and in
Accordance with ASTM-2103.
2. Concreting shall not be allowed without vibration at any time.
3. Curing of concrete shall be done by gunny bags for curing compound.
4. Cement shall be type 1 and in areas having water logging and salinity, Sulphate
resistant cement type 5 may be used. SEC Engineer shall direct to the type of
cement to be used.
5. Water shall be free from silt, organic matter, alkalies or other impurities.
6. The average grain size of sand is 0.35mm and the mud content shall not be more
than 5%.
7. Forms to be used, these shall be sufficiently tight to prevent loss of mortar from
concrete and shall be maintained rigidly in position until concrete has hardened
enough to prevent damage by the removal.
8. If required by SEC Engineer, the concrete foundation sample test of Pole and anchor
shall be carried out. The concrete sample to be crushed after seven days.
9. All lean concrete under reinforced base to be premixed from factory with 250 kg
cement/m2
of concrete minimum strength 14 N/mm2
.
10. Lean concrete 15 cm thick shall be used all around the 15 Cm Dia P.V.C Pipes
running underground.
11. All R.C.C to be premixed from factory with 350 kg cement/m2
of concrete minimum
strength 21 N/mm2
(3000 P.S.I).
12. Sand should be coarse grained, clean and free from all foreign matter.
13. Aggregate should be well graded (19mm Max size), clean and free from all foreign
matter.
14. All steel reinforcing bar to be high yield deformed type conforming to metric BS
444.9 Min yield strength 410 N/mm2
.
15. Reinforcement covers with in concrete to be as follows: Roof Slab 20 mm, Footing
60mm, others 40 mm.
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7 SOIL CLASSIFICATION:
The soils are classified according to the A. B. Chance test probe method. The chance test
probe is a mechanical tool to identify soil in a simple and quick way from the earth
surface without core samples. To find out the soil bearing capacity the soil test probe is
screwed into the soil. As it displaces the soil, probe torque readings are measured in
inch-pounds on a torque gauge. The torque values obtained are translated into soil
classification using the chance Soil Classification Data chart. The table below shows the
soil classification as per A.
B. Chance method and the relevant SEC soil classification to be followed.
Class Description of Soil Type
Probe Values Ibs
(N-m)
SEC Soil
Type
Classification
0 Sound hard rock, un-weathered N. A.
Rock / Dense
Soil
1
Very dense and / or cemented sands coarse
gravel and cobbles
750-1600
(90-208)
2
Dense fine sand, very hard silts and clays
(may be preloaded)
600-750
(78-98)
3
Dense clays, sands and gravel, hard silts
and clays
500-600
(65-78)
4
Medium dense coarse sandy gravel, very
stiff to had silts and clays
400-500
(52-65) Medium
Soil
5
Medium dense coarse sand & sandy
gravels, stiff to very stiff silts and clays
300-400
(39-52)
6
Loose to medium dense fine to coarse
sand, firm to stiff clays & silt
200-300
(26-39) Loose
Soil
7
Loose fine sand, alluvium, loess, soft firm
clays, varied clays, fill
100-200
(13-26)
Table 6: BREAKING CAPACITY OF SOIL IS 1.5 KG/CM2
21. Saudi Electricity Company
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9 Specification of Installation of Duct Bank at Road Crossing
9.1 General:
This specification gives requirements for installation of underground duct banks at road
crossings The. duct bank consists of PVC conduits direct buried in compacted sand or
encased in concrete.
9.2 Excavation:
The excavation for a duct bank shall be completed to its full length at crossing before
any conduit is laid. Possible obstructions might be encountered which would make it
difficult to maintain proper grading or drainage of the duct run.
الحفر مسار
شارع
شارع
الحالة هذه في اختبارات ثالثة احتساب يتم شارع إلى شارع من الحفر اتجاه تغير :) 6 ( رقم مسار
.) فرعي أو رئيس ( الشارع ونوعية العمق حسب دك طبقة لكل
شارع
ثالثة احتساب يتم الحالة هذه في جانب إلى جانب من الواحد الشارع في الحفر تغير : ) 6 ( رقم مسار
طبق لكل اختبارات.الشارع ونوعية العمق حسب دك ة
الحفر مسار
شارعواحد
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Asphalt shall be cut by a motor driven saw. Excavated materials shall be immediately
removed from site and hauled to an approved municipal dumping yard.
Manual digging shall be used at locations where existing underground facilities (e.g.
water pipes, sewage lines, cables etc.) are encountered. Existing facilities uncovered
during excavation shall be protected, shored, braced, and supported, as necessary.
All protective covers, warning tapes, position markers, etc. pertaining to existing
underground utilities shall be preserved during excavation and restored in position during
backfilling.
The excavation shall be properly sheeted and braced, as necessary, to prevent the sides
from caving in due to soft or sandy soil, traffic vibration, etc. All excavations exceeding
1.5 meter depth shall be properly sheeted and braced.
The depth of the duct bank shall be in accordance with the requirement of the
municipality or ministry of communication ( as applicable ) and it shall provide a
minimum cover of 500 mm. The excavation for the duct banks shall provide a minimum
grade or slope of 250 mm per 100 m. The bottom of the excavation shall be carefully
finished to the exact grade required for the duct bank and shall have a minimum bearing
capacity of 140 kpa.
The width of the duct bank shall be as per the figures
Multiple layer duct banks shall be constructed if there is any difficulty to temporarily
cover with steel plate the very wide ( greater than 1300 mm ) open duct banks.
Where the earth walls of the excavation are firm enough to sustain themselves, they may
be used to serve as the forms for a concrete encased duct bank.
9.3 Duct Bank construction
General:
Direct buried concrete encased duct banks shall be constructed with Type DB PVC
conduit.
In laying PVC conduit, each piece of conduit shall be inspected for breakage. Where
jointing conduits, the conduit end without socked only shall be coated with solvent
cement and the conduits joined with a twisting motion to spread the cement.
As far as possible, conduits shall be so installed that the cable will enter and leave
through the socket ends of the conduits. In case of difficulty in arranging this, a straight
coupling shall be installed on the plain end of the conduit and cable shall be pulled
through this coupling.
Direct buried duct bank:
Constructing a direct buried duct bank shall consist of installing conduits with compacted
sand around the conduits. The sand shall be clean, fine, free from organic matter, and
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compacted in 150 mm layers to 85%. Relative density ( ASTM-D-2049 ) at a moisture
content not less than 80%.
Reinforced concrete bulkheads ( precast or cast at site ) shall be installed at each end of
the duct bank. Bulkheads shall be as per the figures concrete shall conform to the
specification of section 6 of this clause and shall be colored or painted red on the top of
the surface.
Concrete encased duct bank:
Construction of a concrete encased duct bank consists of installing the conduits on
spacers or fixing them to the reinforcing steel bars driven inside the ground along the
trench length and pouring the concrete encasement. Spacers or bars for supporting the
conduit are installed at intervals or approximately 2.5 meters.
If the concrete mix is sloppy it may be necessary to weight or brace the duct assembly to
prevent it from floating. Sandbag or other weights can be placed over the conduit spacers.
This is not required if conduits are already fixed to the reinforcing steel bars.
If it is necessary to interrupt the concrete pouring for any appreciable time, as from one
work day until the next, the joint between the pouring shall be made as near vertical as
possible and shall be reinforced with 12 mm dia. Concrete reinforcing bars which extend
in to the concrete at least 600 mm on each side of the joint. Bars shall be placed at each
corner of the duct bank and they shall have a minimum cover of 80 mm of concrete.
Concrete for duct bank construction shall conform to the specification given on section 6
and shall be colored or painted red on the top surface.
9.4 Backfilling and reinstatement:
Backfilling of the duct back excavation shall be in accordance of the requirements of the
municipality or ministry of communications (as applicable). If not specified, backfill
shall be clean, fine sand, free from organic matter, compacted in 250 mm layers to 95%
maximum dry density ( modified Proctor ).
Warning tape shall be laid in the backfill between the duct bank and the base layer of the
roadway. The spacing between the duct bank and the warning tape shall be as large as
site conditions permit up to 500 mm.
Reinstatement of sidewalks, streets, and roads shall be in accordance with the
specification of municipality or ministry of communications ( as applicable ).
9.5 Duct cleaning and inspection:
On completion of a duct bank, a test mandrel and wire brush cleaner shall be pulled
through each conduit. The test mandrel shall be 6mm less in diameter than the nominal
inside diameter of the conduit while the wire brush shall be slightly larger than the
conduit.
The testing and cleaning of a concrete encased duct bank shall be done the day after the
concrete has been poured to eliminate any concrete which may have seeped in to the
ducts.
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A nylon pull line shall be installed in each conduit after cleaning. All conduits shall
remain plugged until cables are installed through them.
9.6 Concrete Specification:
Portland Cement:
Type V ( Sulphate resistant ) conforming to ASTM specification C-150
Aggregates:
All Aggregates shall conform to ASTM specification C-33 and the following:
a. Coarse aggregate – round maximum sized 20 mm.
b. Fine Aggregate – percent of total, 40% to 55%; fineness modulus, 2.6 to 2.9.
Water:
Must be potable, clean and free from deleterious amounts of acids, alkalis or organic
materials . salt water or sea water shall not be used.
Strength:
Minimum strength, 21.0 MPA ( 3,000 psi ) in 28 days.
Slump:
Shall not exceed 150 mm ( based on standard 150 mm dia. test cylinder ).
Ready mixed concrete:
Ready mixed concrete shall be mixed in an approved plant, using approved materials as
specified. Water shall be added at the mixing plant except where haul is greater than one
hour from mixing plant, in which case water shall be added at the jobsite.
Job mixed concrete:
Job mixed concrete shall be mixed in an approved manner, using approved materials as
specified. Each batch must be mixed not less than one minute after all materials are in
mixer.
Reservations:
SEC reserves the right to inspect and/or test all materials and equipment concerned with
the concrete covered by this specification.
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10 General notes on Medium voltage HDD works:
10.1 All dimensions are in millimeters unless indicated otherwise noted.
10.2 The contractor shall submit a directional drilling package containing the
justification for the proposed cable formation/ spacing, PVC conduit , fill
compound ( if any ) and pipe size that will attain the required cable MVA rating
for technical review and approval of SEC.
10.3 Site condition shall be investigated by the contractor. The contractor shall take
full responsibility for maintaining and protecting all existing site utilities, soil
condition and stability.
10.4 It is contractor’s responsibility to provide and install a de- watering system if
found necessary due to high ground water table. The de watering system shall be
reviewed and approved by SEC. contractor shall be also responsible for disposing
off the ground water using water tankers.
10.5 PVC conduit shall be terminated with end bells.
10.6 A minimum of one circuit run of spare ducts shall be provided in every directional
drilling installation. All spare ducts shall have a 13 mm (112’’1 Nylon ) rope
installed inside all cable ducts shall be sealed with the use of duct sealing units.
10.7 Test mandrel ( 6mm less in diameter than the normal inside diameter of the duct )
and wire brush cleaner ( 6mm larger than the duct ) shall be pulled thru to each
duct. A nylon pull line ( 13 mm diameter ) should be installed in each duct line (
power and communication ) after cleaning, construction drawings which indicate
duct line, length and routing shall be verified and field noted in conjunction with
duct testing operation.
10.8 The two ends of every directional drilling installation shall be marked by a sign
post , warning sign applicable arrow sign, another log, a voltage rating plate shall
also be provided, the material, size, paint and color of the voltage rating plate
shall be identical to that of the arrow signs.
10.9 Upon completion of duct bank installation, the contractor shall provide As- built
drawings, showing duct bank location and details to include in the duct bank
location mark. Location shall be referenced from permanent ( existing ) objects.
10.10 End cups shall be provided for all spare ducts.
10.11 Directional drilling shall be used only if other alternative means of crossing are
not possible.
10.12 Ampacity adequacy shall be verified where directional drilling is required.
10.13 backfilling _and reinstatement shall be in accordance of the requirements of
appropriate authority.
10.14 The process of directional drilling shall be as per contractor’s methods of
construction procedures and requirements.
26. Saudi Electricity Company
Distribution Services Sector
CONSTRUCTION STANDARD FOR
UNDERGROUND DISTRIBUTION NETWORK
PART 17: CABLE TRENCHES
Issue Date: 8/2019 Page: 26 of 45
SDCS-02-17 REV.01
10.15 The number of directional drilling conduits shall also depend on required number
of cable circuits and available right of wa
10.16 The details of the directional drilling method tone with description of the
machinery that will. Be used shall be submitted for company review and approval.
the contractor shall explain in details how the required clearance between each
circuit, other circuit and other utilities will be maintained.
10.17 Prior to commencement of any directional drilling work, the contractor shall get
approval and permission from the concerned row approving agencies.
10.18 All the above requirements shall be submitted for company review and approval.
10.19 The joints of the pipes shall be flexible. the pull applied on_ the curved pipes shall
be prescribed by the manufacturer and contractor has to work within these limits.
10.20 The drilling angle from the horizontal shall be with respect to property of site
material.
10.21 The contractor ‘s responsible for damaging any existing underground facility /
relocating & reinstating any existing underground facility for his work.
The typical dimensions for spacing & depth are shown in the section drawing below.
27. Saudi Electricity Company
Distribution Services Sector
CONSTRUCTION STANDARD FOR
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PART 17: CABLE TRENCHES
Issue Date: 8/2019 Page: 27 of 45
SDCS-02-17 REV.01
Cable Trenches Figures
1. Normal trench single LV cable --- Fig. 1
2. Normal trench double LV cable --- Fig. 2
3. Normal trench 3 LV cables --- Fig. 3
4. Micro trench LV cable --- Fig. 4
5. Micro trench MV cable --- Fig. 5
6. Normal trench MV single cable --- Fig. 6
7. Normal trench MV double cable --- Fig. 7
8. Normal trench MV 3 cables --- Fig. 8
9. Normal trench single MV cable 33KV for interconnection between
2 primary substations --- Fig. 9
10.Normal trench double MV cable 33KV for interconnection
between 2 primary substations --- Fig. 10
11.Normal trench MV 3 cables 33 KV for interconnection between 2
primary substations --- Fig. 11
28. Saudi Electricity Company
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CONSTRUCTION STANDARD FOR
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PART 17: CABLE TRENCHES
Issue Date: 8/2019 Page: 28 of 45
SDCS-02-17 REV.01
1-Normal trench single LV cable ---- Fig. 1
2-Normal trench double LV cable ---- Fig. 2
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CONSTRUCTION STANDARD FOR
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PART 17: CABLE TRENCHES
Issue Date: 8/2019 Page: 29 of 45
SDCS-02-17 REV.01
3-Normal trench 3 LV cables ---- Fig. 3
4-Micro trench LV cable ---- Fig. 4
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Issue Date: 8/2019 Page: 30 of 45
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5-Micro trench MV cable ---- Fig. 5
6-Normal trench MV single cable ---- Fig. 6
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PART 17: CABLE TRENCHES
Issue Date: 8/2019 Page: 31 of 45
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7- Normal trench MV double cable ---- Fig. 7
8- Normal trench MV 3 cables ---- Fig. 8
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Distribution Services Sector
CONSTRUCTION STANDARD FOR
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PART 17: CABLE TRENCHES
Issue Date: 8/2019 Page: 32 of 45
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9-Normal trench single MV cable 33KV for interconnection between 2 primary substations ---- Fig. 9
10- Normal trench double MV cable 33KV for interconnection between 2 primary substations --- Fig. 11
33. Saudi Electricity Company
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CONSTRUCTION STANDARD FOR
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Issue Date: 8/2019 Page: 33 of 45
SDCS-02-17 REV.01
11- Normal trench MV 3 cables 33 KV for interconnection between 2 primary substations ---- Fig. 11
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Distribution Services Sector
CONSTRUCTION STANDARD FOR
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PART 17: CABLE TRENCHES
Issue Date: 8/2019 Page: 34 of 45
SDCS-02-17 REV.01
TYPICAL DETAILS OF DIRECT BURIED CABLE AT
CROSSOVER /Figures
1. PVC Conduit ---- Fig. 12
2. PVC Conduit Accessories ---- Fig. 13
3. Typical Cannal Crossing ---- Fig. 14
4. Direct Buried Cable at Crossover ---- Fig. 15
5. Direct Buried Duct Bank 1 of 2 ---- Fig. 16
6. Direct Buried Duct Bank 2 of 2 ---- Fig. 17
7. Concrete Encased Duct bank 1 of 2 ---- 18
8. Concrete Encased Duct bank 2 of 2 ---- 19
9. Service Cable Post ---- Fig. 20
10.Sign Post ---- Fig. 21
11.Medium voltage horizontal directional drilling (HDD) and
installation of Hope (high density polyethylene on road crossing) --
-- Fig. 22
35. Saudi Electricity Company
Distribution Services Sector
CONSTRUCTION STANDARD FOR
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PART 17: CABLE TRENCHES
Issue Date: 8/2019 Page: 35 of 45
SDCS-02-17 REV.01
1- PVC Conduit ---- Fig. 12
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Issue Date: 8/2019 Page: 36 of 45
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2- PVC Conduit Accessories ---- Fig. 13
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Issue Date: 8/2019 Page: 37 of 45
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3- Typical Cannal Crossing ---- Fig. 14
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Issue Date: 8/2019 Page: 38 of 45
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4- Direct Buried Cable at Crossover ---- Fig. 15
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CONSTRUCTION STANDARD FOR
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Issue Date: 8/2019 Page: 39 of 45
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5- Direct Buried Duct Bank 1 of 2 ---- Fig. 16
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Issue Date: 8/2019 Page: 40 of 45
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6- Direct Buried Duct Bank 2 of 2 ---- Fig. 17
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CONSTRUCTION STANDARD FOR
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Issue Date: 8/2019 Page: 41 of 45
SDCS-02-17 REV.01
7- Concrete Encased Duct bank 1 of 2 ---- Fig.18
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CONSTRUCTION STANDARD FOR
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Issue Date: 8/2019 Page: 42 of 45
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8- Concrete Encased Duct bank 2 of 2 ----Fig. 19
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9- Service Cable Post ---- Fig. 20