in a robust metal case and the matur- ity reading is displayed on a decade counter. A separate meter indicates battery state, and a key-operated switch begins operation and resets the
counter.
―
The maturity of concrete is defined as the product of the time in hours from mixing and the temperature of the mix in degrees Centigrade above a base temperature of 10 deg. C. The concrete maturity meter directly and automatically measures and records the maturity of a concrete sample by means of its temperature-sensitive probe which is embedded in the con- crete at the time of pouring, and takes account of variations in ambient tem- perature and internal heating of the sample.
From a knowledge of the concrete mix and maturity the engineer may then estimate the strength of the sample at any time after pouring and strike his shuttering at the earliest practical moment. The measuring temperature range of the probe, -10 to +85 deg. C., and the ambient-tempera- ture range of the electronic unit, -10 to +55 deg. C., are such that the instrument is suitable for use both in heat-cured and ambient-cured con-
cretes.
WASH BASIN
the
A new design of wash-basin Plymouth has been announced by Gerber Plumbing Fixtures Corp., Lin- colnwood, Ill., USA.
Made of vitreous china, it measures 19 x 17 in. and features straight sculp-
Plymouth wash basin
tured lines with two integral recessed self-draining soap dishes, anti-splash rim and concealed front overflow.
The basin has a one-piece fast align- ing hanger and is drilled for a 4in. centreset faucet.
WATERSTOPS
Expandite Ltd. have introduced a complete metric range of rubber and p.v.c. waterstops. The range includes rubber waterstops in widths from 115 to 305mm, p.v.c. centrally placed waterstops in widths from 100 to
240mm and p.v.c. Rearguard water- stops in widths of 190 and 240mm.
A 28-page booklet, available from the firms Civil Engineering Products Division, Chase Road, London, N.W.10, gives full dimensional details of all Expandite waterstops, together with performance figures, shuttering details, joint design recommendations and information on site jointing equip ment.
MEASURER
Electro-optical equipment which ensures pinpoint accuracy over long distances is being used by survey con- sultants working on Hong Kong's cross-harbour tunnel.
The equipment, the Distomat DI-10, transmits a sinusoidal modulat- ed infra-red beam, which is returned after reflection by a prism-reflector. With digital display read-out, it
Distomat D1-10 in use
measures distances of up to 1200 metres to an accuracy within 1 cm.
Sercel of France and Wild Heer- brugg Ltd., Switzerland, are the joint manufacturers.
FIXINGS
Two machine-bolt expansion an- chors, the Korker and the Forway, will secure medium and heavy loads in con- crete, brick or stone.
The Korker comprises a cylindrical lead-antimonial sleeve with a die-cast zinc cone held fast in its base. After the anchor has been set into a pre-drill- ed hole, the user has only to insert a bolt, engage it with the threaded cone in the base and then tighten it. This action pulls the cone upwards into the case, causing the latter to expand out- wards against the walls of the hole and lock securely into position.
Four available diameters of 4, 5/16, 3/8 and 1⁄2 in. have lengths of 7/8, 1, 14 and 11⁄2 in. respectively, with holding strengths in average con- crete of 3,000, 3,700, 6,500, 7,200 lb.
Based on a split shell of zinc alloy, incorporating gripping ridges on its sides and a captive zinc-alloy tapered nut in its base, the Forway anchor
Forway anchor
operates in much the same way as the Korker, except that it splits open in four directions.
The Korker lengths are longer at 1, 12, 1% and 24 in. with holding capacities of 4,000, 4,500, 7,300 and 9,200 lb. in average concrete.
The makers are U.S. Expansion Bolt Co. (GB) Ltd., Polesdon Lane, Ripley, Surrey, UK. Agents for S.E. Asia are Vaughan Engineering Co., Hong Kong.
LUMINAIRES
Surface-mounted, shallow, module. matched luminaires introduced by Sunbeam Lighting Co. Inc., 777 E. 14th Place, Los Angeles, USA, fit any ceiling construction.
The new series, known as Modulux 14000, comprises a total of seven basic modules with exact overall footage dimensions for perfect tile or grid alignment, especially in continuous rows. They bolt end to end.
The 1ft. wide and 2ft. wide units are available with three types of panel frames, including 'frameless' or plastic reinforced type, and flush and regress- ed aluminium, and with more than 15 acrylic prismatic panels and trans- lucent light diffusers. Hinging is from
Modulux luminaire
either side of the fixture for main- tenance convenience and is designed to prevent accidental displacement.
The luminaires have the following dimensions: 1 x 4ft., 1 x 8ft., 2ft. square, 2 x 4ft., 2 x 8ft., 3ft. square, and 4ft. square. The shapes use from two to eight lamps. Heavy guage weld- ed steel is used for the structure.
Far East BUILDER, June 1970
39