ITEM 100 – CLEARING AND GRUBBING
100.1 Description
This item shall consist of clearing, grubbing, removing and disposing all vegetation and debris as
designated in the Contract, except those objects that are designated to remain in place or are to
be removed in consonance with other provisions of this Specification. The work shall also include
the preservation from injury or defacement of all objects designated to remain.
100.2 Construction Requirements 100.2.1 General
The Engineer will establish the limits of work and designate all trees, shrubs, plants and other
things to remain. The Contractor shall preserve all objects designated to remain. Paint required
for cut or scarred surface of trees or shrubs selected for retention shall be an approved asphaltum
base paint prepared especially for tree surgery.
Clearing shall extend one (1) meter beyond the toe of the fill slopes or beyond rounding of cut
slopes as the case maybe for the entire length of the project unless otherwise shown on the plans
or as directed by the Engineer and provided it is within the right of way limits of the project, with
the exception of trees under the jurisdiction of the Forest Management Bureau (FMB).
100.2.2 Clearing and Grubbing
All surface objects and all trees, stumps, roots and other protruding obstructions, not designated
to remain, shall be cleared and/or grubbed, including mowing as required, except as provided
below:
1. (1) Removal of undisturbed stumps and roots and nonperishable solid objects with a
minimum depth of one (1) meter below subgrade or slope of embankment will not be
required.
2. (2) In areas outside of the grading limits of cut and embankment areas, stumps and
nonperishable solid objects shall be cut off not more than 150 mm (6 inches) above the
ground line or low water level.
3. (3) In areas to be rounded at the top of cut slopes, stumps shall be cut off flush with or
below the surface of the final slope line.
4. (4) Grubbing of pits, channel changes and ditches will be required only to the depth
necessitated by the proposed excavation within such areas.
5. (5) In areas covered by cogon/talahib, wild grass and other vegetations, top soil shall be
cut to a maximum depth of 150 mm below the original ground surface or as designated by
the Engineer, and disposed outside the clearing and grubbing limits as indicated in the
typical roadway section.
Except in areas to be excavated, stump holes and other holes from which obstructions are
removed shall be backfilled with suitable material and compacted to the required density.
If perishable material is burned, it shall be burned under the constant care of component
watchmen at such times and in such a manner that the surrounding vegetation, other adjacent
property, or anything designated to remain on the right of way will not be jeopardized. If permitted,
burning shall be done in accordance with applicable laws, ordinances, and regulation.
The Contractor shall use high intensity burning procedures, (i.e., incinerators, high
stacking or pit and ditch burning with forced air supplements) that produce intense burning with
little or no visible smoke emission during the burning process. At the conclusion of each burning
session, the fire shall be completely extinguished so that no smoldering debris remains.
In the event that the Contractor is directed by the Engineer not to start burning operations
or to suspend such operations because of hazardous weather conditions, material to be burned
which interferes with subsequent construction operations shall be moved by the Contractor to
temporary locations clear of construction operations and later, if directed by the Engineer, shall
be placed on a designated spot and burned.
Materials and debris which cannot be burned and perishable materials may be disposed
off by methods and at locations approved by the Engineer, on or off the project. If disposal is by
burying, the debris shall be placed in layers with the material so disturbed to avoid nesting. Each
layer shall be covered or mixed with earth material by the land-fill method to fill all voids. The top
layer of material buried shall be covered with at least 300 mm (12 inches) of earth or other
approved material and shall be graded, shaped and compacted to present a pleasing appearance.
If the disposal location is off the project, the Contractor shall make all necessary arrangements
with property owners in writing for obtaining suitable disposal locations which are outside the limits
of view from the project. The cost involved shall be included in the unit bid price. A copy of such
agreement shall be furnished to the Engineer. The disposal areas shall be seeded, fertilized and
mulched at the Contractor’s expense.
Woody material may be disposed off by chipping. The wood chips may be used for mulch,
slope erosion control or may be uniformly spread over selected areas as directed by the Engineer.
Wood chips used as mulch for slope erosion control shall have a maximum thickness of 12 mm
(1/2 inch) and faces not exceeding 3900 mm2 (6 square inches) on any individual surface area.
Wood chips not designated for use under other sections shall be spread over the designated
areas in layers not to exceed 75 mm (3 inches) loose thickness. Diseased trees shall be buried
or disposed off as directed by the Engineer.
All merchantable timber in the clearing area which has not been removed from the right of
way prior to the beginning of construction, shall become the property of the Contractor, unless
otherwise provided.
Low hanging branches and unsound or unsightly branches on trees or shrubs designated
to remain shall be trimmed as directed. Branches of trees extending over the roadbed shall be
trimmed to give a clear height of 6 m (20 feet) above the roadbed surface. All trimming shall be
done by skilled workmen and in accordance with good tree surgery practices.
Timber cut inside the area staked for clearing shall be felled within the area to be cleared.
ITEM 201 – AGGREGATE BASE COURSE 201.1 Description
This Item shall consist of furnishing, placing and compacting an aggregate base course on a
prepared subgrade/subbase in accordance with this Specificaton and the lines, grades,
thickness and typical cross-sections shown on the Plans, or as established by the Engineer.
201.2 Material Requirements
Aggregate for base course shall consist of hard, durable particles or fragments of crushed
stone, crushed slag or crushed or natural gravel and filler of natural or crushed sand or other
finely divided mineral matter. The composite material shall be free from vegetable matter and
lumps or balls of clay, and shall be of such nature that it can be compacted readily to form a
firm, stable base.
In some areas where the conventional base course materials are scarce or non-available, the
use of 40% weathered limestone blended with 60% crushed stones or gravel shall be allowed,
provided that the blended materials meet the requirements of this Item.
The base course material shall conform to Table 201.1, whichever is called for in the Bill of
Quantities
Pay Item Number Description Unit of Measurement
200 Aggregate Subbase Course Cubic Meter
41
Table 201.1 – Grading Requirements
Sieve Designation Mass Percent Passing
Alternate US
Standard, mm Grading A Grading B
Standard
50 2” 100
37.5 1-1/2” - 100
25.0 1” 60 – 85 -
19.0 3⁄4” - 60 – 85
12.5 1⁄2” 35 – 65 -
4.75 No. 4 20 – 50 30 – 55
0.425 No. 40 5 – 20 8 – 25
0.075 No. 200 0 – 12 2 – 14
The fraction passing the 0.075 mm (No. 200) sieve shall not be greater than 0.66 (two
thirds) of the fraction passing the 0.425 mm (No. 40) sieve.
The fraction passing the 0.425 mm (No. 40) sieve shall have a liquid limit not greater than
25 and plasticity index not greater than 6 as determined by AASHTO T 89 and T 90, respectively.
The coarse portion, retained on a 2.00 mm (No. 10) sieve shall have a mass percent of
wear not exceeding 50 by the Los Angeles Abrasion test determined by AASHTO T 96.
The material passing the 19 mm (3/4 inch) sieve shall have a soaked CBR value of not
less than 80% as determined by AASHTO T 193. The CBR value shall be obtained at the
maximum dry density (MDD) as determined by AASHTO T 180, Method D.
If filler, in addition to that naturally present, is necessary for meeting the grading
requirements or for satisfactory bonding, it shall be uniformly blended with the base course
material on the road or in a pugmill unless otherwise specified or approved. Filler shall be taken
from sources approved by the Engineer, shall be free from hard lumps and shall not contain more
than 15 percent of material retained on the 4.75 mm (No. 4) sieve.
201.3 Construction Requirements 201.3.1 Preparation of Existing Surface
The existing surface shall be graded and finished as provided under Item 105, Subgrade
Preparation, before placing the base material.
201.3.2 Placing
It shall be in accordance with all the requirements of Subsection 200.3.2, Placing.
201.3.3 Spreading and Compacting
It shall be in accordance with all the requirements of Subsection 200.3.3, Spreading and
Compacting.
201.3.4 Trial Sections
Trial sections shall conform in all respects to the requirements specified in Subsection
200.3.4.
201.3.5 Tolerances
Permitted variation from design ±10 mm
THICKNESS OF LAYER
Permitted variation from design +5 mm
LEVEL OF SURFACE -10 mm
Permitted SURFACE IRREGULARITY
Measured by 3-m straight-edge +5 mm
Permitted variation from design ± 0.20%
CROSSFALL OR CAMBER
Permitted variation from design ±0.10%
LONGITUDINAL GRADE over
25 m in length
201.4 Method of Measurement
Aggregate Base Course will be measured by the cubic meter (m3). The quantity to be paid
for shall be the design volume compacted in-place as shown on the Plans, and accepted in the
completed base course. No allowance shall be given for materials placed outside the design limits
shown on the cross- sections. Trial sections shall not be measured separately but shall be
included in the quantity of aggregate base course.
201.5 Basis of Payment
The accepted quantities, measured as prescribed in Section 201.4, shall be paid for at the
contract unit price for Aggregate Base Course which price and payment shall be full compensation
for furnishing and placing all materials, including all labor, equipment, tools and incidentals
necessary to complete the work prescribed in this Item.
Payment will be made under:
Pay Item Number Description Unit of Measurement
201 Aggregate Base Course Cubic Meter
