Determination of mechanical properties for cement treated. Section 1 general sections are reserved in the standard specifications for correlation of special provisions and revised standard specifications with the standard specifications and for future expansion of the standard specifications the specifications are expressed in u. Road networks are most important infrastructure of our country. This was based on the philosophy that a thicker section. Cement treated base is an ideal solution for outdoor storage lots, parking lots, or industrial aggregate type yards. Cement treated base safety data sheet according to federal register vol.
Be alert for new or revised specifications that may affect the current manual guidance for contract administration. Improving the quality and strength of sub base and. Uses higher dosages of cement cement treated base ctb intended to create a structural base uses higher dosages of cement typically used for faa projects full depth reclamation fdr intended to create a structural base used widely to address existing pavement complete structural failures uses higher dosages. The using of ctab,binder and surface course present the best economical choice. The strength of cement treated aggregate base represented by california bearing ratio cbr and compressive strength with percent higher than those to base by 46% and 58% respectively. Cta consists primarily of base aggregate mixed with a specified percentage of hydraulic cement by weight and field compacted at moisture contents that are slightly greater than the optimum moisture content. Cement treated base ctb is a nonconventional method used in road bases materials to improve its engineering properties due to the hardening of cement when moisture is present and extends the. Cement modified soil cms is a soilaggregate material that has been treated with a relatively small proportion of portland cement in order to amend its undesirable properties so that they are suitable for use in subgrade or foundation construction. D020 partial panel concrete replacement 06202019 d521 trench repair reinforced concrete pavement 12202012 32 11 23 flexible base courses 12202012 32 11 29 lime treated base courses 12202012 32 11 33 cement treated base courses 08212015 32 11 37 liquid treated soil stabilizer 12202012 32 12 16 asphalt paving. Various military agenciesdepartments army, air force, navy, marine corps also allow the use of. Cement treated base is a mixture of aggregate material, granular soils combined with prescribed amounts of cement and water that hardens after compaction and curing to form a durable paving. The mixed material shall be spread, shaped, and compacted in accordance with these specifications and in. Cement treated base ctb is an intimate mixture of aggregate material andor granular soils combined with measured amounts of portland cement and water that hardens after compaction and curing to form a durable paving material. Interpretation of geotechnical properties of cement treated soils.
Mix and compact cement, water, and subgrade or base with or without asphalt concrete pavement in the roadway. There is one way to make road durable, it is by improving the pavement strength. The completed ctb must be adequately cured to both let the cement hydrate. Ufgs 32 11 34 portland cementstabilized base or subbase. More durable than aggregate surface, and can withstand heavy truck and equipment traffic with less dust. The goal of microcracking is to prevent severe, wide.
Pdf a study on cement treated base using crushed bricks as aggregate pritam debnath and mohini saha academia. The contractor shall remove the remaining portion of concrete pavement slab by lifting and placing directly into haul trucks. Cement treated bast ctb is a compacted mixture of graded aggregate, cement, and water, which is used as a base course for the construction of highways, airport runways and taxiways. Measurement by the cubic yard in final position and square yard is a plans quantity measurement. The aggregate shall be select granular materials, comprised of crushed or uncrushed.
The mixed material shall be spread and shaped with a. Service performance of cementtreated bases as used in. Michigan department of transportation bureau of aeronautics standard specification p304 cement treated base course description 1. This guide specification covers the requirements for portland cement stabilized base or subbase for airfields, roads and streets. Non treated, 5%, and 10% cement treated soils displayed ductile, planar, and splitting type of failure, respectively. Index terms cement treated sub base for bituminous pavement. Soil cement stabilization institute for transportation. Furnish uncontaminated materials of uniform quality that meet the requirements of the plans and specifications. This guide specification covers the requirements for portland cement stabilized base or subbase and lean concrete bases or subbases.
This test method does not purport to address all of the safety problems associated with its use. Ctb can be mixed inplace with onsite soils or mixed in a central plant or pugmill depending on the project requirements. Cementtreated base ctb is a strong, frostresistant base for a concrete or asphalt pavement wearing surface. A bituminous or portland cement concrete wearing course is placed on the ctb to complete the pavement structure. The strength of cement treated base should be kept within designated strength limits. The base course shall be built in a series of parallel lanes using a plan of processing that reduces longitudinal and transverse joints to a minimum. This section provides guidelines for inspecting cement treated base ctb. Cementtreated base ctb is a general term that applies to an intimate mixture of native soils andor manufactured aggregates with measured amounts of portland cement and water that hardens after compaction and curing to form a strong, durable, frost resistant paving material. The mixed material shall be spread, shaped, and compacted in accordance with these specifications and. Cementtreated base ctb is an intimate mixture of aggregate material andor granular soils combined with measured amounts of portland cement and water that hardens after compaction and curing to form a durable paving material. The contractor shall be solely responsible for the cement treated base either batched at andor delivered to the site. The strength of cement treated aggregate base represented by california bearing ratio cbr and compressive strength with percent higher than.
Service performance of cement treated bases as used in composite pavements ernest zube, c. Contact with powerful oxidizing agents may cause fire andor explosions see section 10 of sds. It not only saves money but also helps to increase life cycle of roads. Item section aggregate 10101, 10102 ncdot 2012 standard specifications. Cta could be used in both flexible and rigid pavement structures. The construction manual contains policies and procedures related to the duties of caltrans division of construction personnel, is for information only, and is intended as a resource for personnel engaged in contract administration. Section 301soil cement construction page 3 mix and place cement treated base or subbase only when the weather permits the course to be finished without interruption in the time specified. Revised and simplified definition of lot size and partial lot in p401, p403, p501, and. Treated base or soil cement specimens an arizona method 1. The goal of microcracking is to prevent severe, wide cracks from forming and thus reduce the risk of problematic.
Abstract reclaimed asphalt pavement rap and granular base materials were collected from stockpiles in six txdot districts to evaluate the feasibility of using high rap content mixes for base course applications. Total dust containing silica, respirable silicacontaining dust and respirable crystalline silica quartz levels should be monitored regularly to determine worker exposure levels. The primary difference between ctb and soil cement is that ctb usually utilizes a graded aggregate instead of the native soils. Factors that can influence shrinkage cracking in soil cement bases are. Adhere to ufc 002 unified facilities guide specifications ufgs format standard when editing. The versatility of cement is critical to the success in this pavement solution because site conditions and soil types from gravel to clays can easily change during or between projects and cement acts as a universal stabilizer. Microcracking for reduced shrinkage in cementtreated base. Description mix and compact cement, water, and subgrade or base with or without asphalt concrete pavement in the roadway. It is the responsibility of whoever uses this test method to consult and establish appropriate safety and health practices.
Cement treated base is a general term that applies to a mixture of native soils andor manufactured aggregates with measured amounts of portland cement and water that is compacted and cured to form a strong, durable, frostresistant paving material. A well designed, constructed, and properly maintained cement stabilized base will normally outlast several asphalt overlays, providing decades of low maintenance service. Materials furnish uncontaminated materials of uniform quality that meet the requirements of the plans and specifications. Ufgs 32 11 33 cement stabilized base subbase course at. Lreated base ctb pavements basically consist of a layer of. The contractor will not be allowed to use hydraulic rams on excavators that may damage the cement treated base below the pavement to be removed. This paper will look at the types and causes of reflective cracking in cement stabilized pavement bases and what techniques are available to minimize them for. Final draft update of item p304 cementtreated base course 105 description 3041. Guide to cementtreated base ctb 2 asphalt unstabilized cementstabilized figure 1. Added new p307 cement treated permeable base course ctpb. Cementtreated base safety data sheet according to federal register vol. Mix and place materials only when the moisture content of the soil to be used in the mixture meets the limits specified in this subsection.
Evaluation and mix design of cementtreated base materials. Ctb consists of native soils, gravels, or manufactured aggregates blended with prescribed quantities of cement and water. This guide specification covers the requirements for portland cementstabilized base or subbase for airfields, roads and streets. Minimizing reflective cracking in cementstabilized. Unstabilized bases have high deflection due to low stiffness, which results in high surface strains and eventual fatigue cracking. Cement treatment of an aggregate base layer is an enhancement to the road foundation support when poor subgrade conditions are encountered. Cement treated base will be measured by the ton, cubic yard, or square yard as a composite mixture of cement, flexible base, and recycled materials. In cementtreated base construction the objective is to obtain a thorough mixture of an aggregategranular material with the correct quantity of portland cement and enough water to permit maximum compaction. Characterization and structural design of cementtreated base k.
Mixes containing 100%, 75% and 50% rap treated with portland cement of 0%, 2%. The aggregate shall be select granular materials, comprised of crushed or uncrushed gravel andor stone, or recycled cement concrete. For 10% cement treated soils pore pressures rose rapidly to confining pressure s resulting in zero effective confining pressure at failure. Final draft update of item p304 cement treated base course 105 description 3041. Notify the engineer of the proposed material sources and of changes to material. Damage behavior of cementtreated base material sciencedirect. The higher stiffness provided by cementstabilized bases produces lower deflections, resulting in lower surface strains and. Cement modified soil cms is a soilaggregate material that has been treated with a relatively small proportion of portland cement in order to amend its undesirable properties so that they are suitable. Cement treated base ctb is a cement stabilized material which becomes more important to a modern road pavement under a better performance perspective. Cement treated base ctb has sufficient cement content to develop considerable cohesion and strength. Characterization and structural design of cementtreated base.