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Showing posts from May, 2020

Concrete works

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Concrete ; A homogeneous mixture of -- • Concrete compaction must attained to reduce entrapped air content and flow concrete mixture. Not more than 2% air content acceptable in fresh concrete. • Compaction executed by needle vibrator rpm varies from 1000 to 15000. • Vibrator immerge in concrete vertically and retain in concrete  from 30 second to 2 minutes. • Vibrator must placed  not more than @ 600mm or  8-10 times diameter of needle. • Needle are available for concrete compaction 40 to 100 mm diameter. • Concrete pour by layer wise and in no cases layer not be more than 600 mm thick. To feed bonding hydration process concrete curing immediately need to attain on hardened surface. Impervious sheeting or burlap cloth @ 290gm/ sqm , membrane  curing compound or potable water can be used for the purpose according to availability and approval. Continuous curing upto 72 hrs minimum required and at least 7 days proposed as per ...

Asphalt paved road construction guide

s ampling Loose asphalt mixture sample to be collect @ every 300 tons or once in a day at least. Checking parameter as follows-- Temperature, minimum 139 degree C. Asphalt binder content Mineral aggregate gradation Theoretical maximum specific gravity Marshal stability and flow Air voids in compacted mixture Compacted core sample of 100 mm dia @ 1 per 300 Rmtr or once in a day at least. Checking parameter as follows—        a)Thickness of specimen must be within (+-)10 mm for base course and (+-)6mm for wearing course        b)Degree of compaction 93-95% of max. theoretical specific gravity for base course and 93-96% for wearing course        c)Bulk specific gravity and bulk density        d)Air voids in compacted mixture        e)Marshal stability and flow Laboratory report for above to be submit within 24 hours fr...

Non-Conformance Report

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Non Conformance Report : Non conformance is an instance when a product does not meet product specifications — irrespective of  nonconformity is major or minor. It is the policy that processes , activities, products which do not conform to plans and specifications shall be identified, documented and dis-positioned in a formal and consistent manner. Construction field shouldn't conflict with-- Quality Action Notice /Corrective Action Request : The essence of CAR is to conduct investigation on a problem which already happened and needs root cause analysis and resolution to prevent recurrence. NCR subjected to as follows-- Closure of Non Conformance report Re-inspection and work check according to disposition  If  acceptable  then sign ,date and close Unacceptable  : “Engineering concurrence”  stated-- only after ensuring that adequate measures have been taken to prevent inadvertent use of the unacceptable item. Work shall be re performed ...