High performance granular base and subbase materials incorporating reclaimed asphalt concrete pavement by cong luo, b. The objective of this study is to establish a satisfactory method of determining maximum density of cohesionless material, such as subbase, that will provide compaction criteria for these materials and be compatible with current methods of density determinations in the field. The construction period of the contract will be 180 days. Granular a means a set of requirements for dense graded aggregates intended for use as granular base within the pavement structure, granular shouldering, and backfill. National competitive bidding will be conducted in accordance with adbs single. Maximum dry density and optimum moisture content 1. The surface shall be prepared at least one but not more than three kilometres in advance of placing granular base course. Sand granular material having at least 90 percent passing the no. Frost susceptibility of subbase gravel used in pearl. The present serviceability index psi is the primary measure of serviceability. Pdf determination of the adequate thickness of granular. Eng a thesis submitted to the school of graduate studies in partial fulfillment of.
Concrete shall be laid between the steel forms and a precast concrete rail acting, as a stop end and also rail to be used for surface vibration. Dirt, gravel, and low volume road program april, 2015. Application description granular base user guidelines. Gradation or distribution of different sized stones. Nov 25, 2019 all books are in clear copy here, and all files are secure so dont worry about it. Download fulltext pdf determination of the adequate thickness of granular subbase beneath foundations article pdf available january 2011 with 547 reads. Mechanistically, this configuration provides a stronger reaction platform than unbound subgrades or sub bases, allowing increased granular base compaction during construction, and it also has the potential to take advantage of the compressive stresses induced in the granular aggregate base owing to the presence of the stiff underlying layer.
Spread the subbase material evenly and compact to at least 95 percent of the maximum unit weight, at a less thanoptimum moisture content, for. Highways local services technical consultancy appendix b palette of materials outer area standard treatment. Trbs national cooperative highway research program nchrp. Aggregates for use as granular base tend to be densegraded with a maximum size of 50 mm 2 in or less, while granular subbase can have a nominal maximum size commonly up to 100 mm 4 in. Psi ranges from 0 to 5 where 0 means the existing road condition is. Additional clauses inserted to improve clarity on assessment of. Idot bureau of materials page 1 mistic payitemmaterial. When the source of material for a granular subbase has been approved by the. In highway engineering, subbase is the layer of aggregate material laid on the subgrade, on which the base course layer is located.
A guide to airfield pavement design and evaluation 3rd edition february 2011 construction support team. Surface preparation shall be performed on all existing unpaved surfaces prior to placing granular base course thereon. Densities for use in iowa department of transportation. Concentrated flow stabilization ditches, outlets ton. In addition to applications requiring graded aggregates, pit run blast furnace slag is extensively used for subbase construction in some areas. Granullar sub base after the earth work the subbase of the road is constructed with granular material. Aggregates are used for all types of base and subbase construction. The measured stresses, strains and deflections beneath a rolling wheel load were compared with the corresponding calculated values, to determine whether theory could be used for the design of pavements in which bituminious roadbase. Construct a granular subbase as a component of an optional base. All the resilient modulus loadtime history data files, shear strength and aggregate index properties. National competitive bidding will be conducted in accordance with adbs single stage. Figure 10 effect of granular sub base on the modulus of subgrade reaction k for. Psi serviceability is the ability of a specific section of pavement to serve traffic in its existing conditions.
Granular material for use in sub base courses shall be a naturally occurring gravel, blended as necessary with fine or coarse material and screened to produce the specified gradation. The current gradation specification for granular subbase material at the start of this. Granular b means a set of requirements for wellgraded aggregates intended for use as granular subbase within the pavement structure and granular backfill. This simple procedure consisted of coring out approximately a 411 diameter hole to a depth of 45, filling the hole with 1 liter of water, and timing how long it took to drain from the hole. Check with the district bureau of materials to see if this special provision should be used. If unstable material is to be excavated from the embankment or other specialized procedures. Application description granular base user guidelines for. Bound base material bbm any material equivalent to a granular subbase or better, which uses a cement or bituminous binder. The thickness of the unbound granular sub base layers is determined from the subgrade condition california bearing ratio andor resilient modu lus and design traffic including traffic during. Subbase and hydraulically bound materials hbm subbase and hydraulically bound materials hbm treat existing soil to make hbm subbaseballast application.
Points are awarded based on the percentage of pavement area for which sub. Secondly, if you have a base material with a cbr of 30, then you have a very poor base material the basis of the correlations is for a base cbr100. Relative density has often been used for foundation and earth dam construction control, but it has not been used extensively for compaction control of highway sub base materials. However, while base density is maximized at fines content between 6 and 20 percent, loadcarrying capacity decreases when the fines content exceeds about 9 percent. The following densities should be used for estimating quantities of granular material. Procedures for qc and qa and referee testing protocols are incorporated. Design guide for subgrades and subbases iowa state university.
Granular sub base gsb is constructed with well graded granular soil, maintaining suitable moisture content and compacted in layers not exceeding 100mm. Subbase is often the main loadbearing layer of the pavement. A guide to airfield pavement design and evaluation 3. Options 1 or 2 may be used for the following tests, if there is more than one option. Determination of the adequate thickness of granular subbase beneath foundations. This borrow area is located at offset distance of 2 km on lhs towards. Andersen atechnical university of denmark, brovej 118, dk2800 kgs.
Consultant materials for sub base and base course 3. Read chapter chapter three granular base and subbase construction practices. The work required for cement treated granular base and cement treated granular subbase is detailed in subsections 315. Its role is to spread the load evenly over the subgrade. It may be omitted when there will be only foot traffic on the pavement, but it is necessary for surfaces used by vehicles.
These specifications govern all operations necessary for and pertaining to the production of. All books are in clear copy here, and all files are secure so dont worry about it. Granular soil granular soil will be defined as soil that is noncohesive with 35 % or less passing the no. This site is like a library, you could find million book here by using search box in the header. Intended for the western area of district approximate dividing line.
Appendix b palette of materials part 02 x sections. The thickness of the unbound granular subbase layers is determined from the subgrade condition california bearing ratio andor resilient modu lus and design traffic including traffic during. This specification covers the material requirements for aggregates for use in base, subbase, select subgrade, granular surface, shouldering, and backfill material. Select one of the materials listed below and conform to the following. Granular backup and restore about docave granular backup and restore docave granular backup and restore for sharepoint 2010, sharepoint 20, and sharepoint 2016 ensures a resiliency of service in the event of a disaster and quickly recovers lost. Frost susceptibility of subbase gravel used in pearlchain bridges. Even though the figure shows a straight line correlation between the different test parameters, that is not so, particularly with respect to the resilient modulus vs. Granullar sub base pradhan mantri gram sadak yojana. Spread the subbase material evenly and compact to at least 95 percent of the maximum unit weight, at a less thanoptimum moisture content, for its entire thickness.
Base aashto design guide bender36 structural op 16 jun 10 08. Pdf serviceability design of granular pavement materials. Characterization of representative aggregate base and granular subbase. Chapter three granular base and subbase construction practices. Permeability of granular subbase materials iowa publications online.
Ctsb cement treated sub base includes all types of cement and chemical stabilized sub bases cvpd commercial vehicles per day dbm dense bituminous macadam fwd falling weight deflectometer gb granular base gdp gross domestic product ggrb gap graded mix with rubberized bitumen gsb granular sub base. Granular subbase gsb is constructed with well graded granular soil, maintaining suitable moisture content and compacted in layers not exceeding 100mm. For maximum base stability, the granular base should have sufficient fines to just fill the voids and the entire gradation should be close to its maximum density. Granular backup and restore about docave granular backup and restore docave granular backup and restore for sharepoint 2010, sharepoint 20, and sharepoint 2016 ensures a resiliency of service in the event of a disaster and quickly recovers lost or corrupted content with database or granular restores. A guide to airfield pavement design and evaluation. Nominal maximum andor minimum sized stone in mix the nominal size distribution of an aggregate specification is defined as the range of sieve openings through which 100% of the aggregate can pass. British standard bs a publication of the british standards institution.
The material is also suitable for all kind of embankment and backfill. Our specification says that a granular base bayer shall have a minimum cbr of 60% and a granular subbase layer of 30%. S4 granular base and aggregates page 7 of 7 final acceptance of the base course is at the authority of the city engineer and will immediately precede paving. Granullar sub base after the earth work the sub base of the road is constructed with granular material. Subbases may be constructed of granular materials, cementtreated materials, lean concrete, or opengraded, highlypermeable materials, which may be stabilized or unstabilized. Granular pavement base and subbase materials covers the requirements for the granular material comprising coarse and fine aggregate particles the proposed mix. Pdf design charts for drainage capacities of granular subbases. Procedures for qc and qa and referee testing protocols. A guide to airfield pavement design and evaluation dmg27. Pdf the main purpose of providing granular subbase gsb in highway pavements is to serve stability and drainage functions.
Chapter three granular base and subbase construction. Any pavement or structure placed on a base course without expressed city engineer approval is subject to removal at the contractors expense. Relative density has often been used for foundation and earth dam construction control, but it has not been used extensively for compaction control of highway subbase materials. Permeability of highway base and subbase material vtrans. Granular material for use in subbase courses shall be a naturally occurring gravel, blended as necessary with fine or coarse material. Best value granular material for road foundations mndot. This simple procedure consisted of coring out approximately a 411 diameter hole to a depth of 45, filling the hole with 1 liter of water, and timing how long it. Compaction is done till required density is achieved as per the design.
The measured stresses, strains and deflections beneath a rolling wheel load were compared with the corresponding calculated values, to determine whether theory could be used for the design of pavements in which bituminious roadbase is substituted for granular sub base. This work consists of constructing a granular subbase on a surface approved by the engineer. Dirt, gravel, and low volume road program april, 2015 summary. The department standard specifications, section 106. The contractor shall provide the engineer with at least six days advance notice of.
650 985 1419 332 1476 349 266 243 203 46 1043 1645 1052 1612 55 117 332 685 1606 41 1586 1153 773 1673 1394 885 823 406 739 1194 10 167 243 1540 578 318 313 1464 1025 702 910 69 357 48 1268 818 1038 1262 602