۴۸-۲۴-Inch-Manhole-No-Step منهول بدون پله ۲۴ الی ۴۸ اینچ NOTES: UNLESS OTHERWISE SPECIFIED. ۱. ALL DIMENSIONS ARE IN DECIMAL INCHES. ۲. PRECAST MATERIALS AND MANUFACTURING METHODS SHALL CONFORM TO ASTM C-478. ۳. CONCRETE SHALL HAVE A MINIMUM COMPRESSIVE STRENGTH F C= 4000 PSI AT 28 DAYS. ۴. THE PORTLAND CEMENT USED IN THE PRECAST SECTIONS SHALL […]