The firm under takes the following specialist work but not limited to this scope of work only, but expands in other civil Works.
We specialize in:
- Piling over Land & Water.
- Underpinning of Buildings.
- Retaining Wall Piling.
- Sheet Piling.
- Construction of Jetty’s.
- Static Pile Load Testing
- Ground Investigation Works.
- Rotary Boreholes
- Over-water Investigations
Piling
The company offers various types of PILE FOUNDATION as and where conventional foundation cannot support the dead and live load of the structure.
The firm provides:
- Pre-cast concrete Piles of 300mm to 600mm diameter.
- Driven steel Piles may it be “H” section, Tubular section or Sheet piles.
- Bored Cast In-situ Piles ranging from 300mm to 1500mm diameter.
- Driven Cast In-situ Piles with Enlarged Base. Commonly known as “FRANKI PILE”.
- Secant Piles form 500mm to 800mm diameter.
Such foundations are generally for Bridges, Harbors and High Rise Buildings etc.
Soil Investigation
Land and Marine
This service is offered for all types of construction and production lines. This can cover soils (clay, sand, silts, gravels, boulders etc.) and Rocks.
The firm is equipped with Percussion and Rotary rigs, field test equipment to cover the requirements to satisfy International Standards. Work can be undertaken covering Roads, Bridges, Water Dams, High Rise Buildings, Airports, Raw Material exploration. The service of Lab Testing and Engineering Report can be arranged and provided by the firm under one roof.
Grouting
The firm under takes all kinds of grouting works. May it be for Foundation, Sealing Water, Protection and Retaining non supporting soils etc. The firm is fully equipped for such works.
Water Well Drilling
The firm has specialized in installing High Yield Shallow Wells as large as 1000mm dia and over, for bulk production line. The firm also undertakes to install deep-water wells in any part of the country.
The company not only undertakes the above specialized works, but is now expanding into construction of small scale Bridges, Buildings and Roads etc. In short the field of work is vast and wide and the firm is ready to take any challenging scope of work, may it be Land or Over Water (Marine).
- Ground Anchor installation may it be Horizontal, Vertical or at an inclination angle. In order to improve and reinforcement to the existing structure and soil strata.
- Grouting and Guniting of porous and poor concrete and structural concrete.
- Water proofing of basement, foundation sub-soil and sealing leakage by drilling and pumping sikament component.
Below are a few examples of such specialized works carried out by the Company.
- Water proofing of Kenyatta Conference Hall Basement by drilling into the concrete slab and pumping sika waterproofing component step by step till all the leakage area was sealed.
- Anchorage and Tensioning of soil structure for Posta Bank Building and Kimathi House etc. by drilling at an angle to six meters, installing anchor bars of 32mm to 40mm diameter. Grouting the same and Tensioning the same against 600mm x 600mm x 25mm plate.
Guniting poor or exposed concrete structure for K.P.A. Mombasa Port and the Oil Refinery. The exercise was carried out to restore sound concrete by exposing decomposed and poor concrete up to the reinforcement and spray fresh concrete.
Bored Cast Insitu-Piles
This type of Piles are installed by using Light Tripod Rigs.
This plant is light and suited to congested or remote Sites, or Sites with uncertain ground conditions. Bored Pile is a versatile pile with an enlarged base and compacted pile shaft, which ensures efficient utilization of materials of construction and soil.
Method
Soil is removed by means of percussion tools working off light tripod rigs where necessary, the holes are temporary cased by 300mm, 400mm, 500mm, 600mm, 800mm and 1,000mm diameter tubes, screw coupled. In some cases large size piles are used upto 1,500mm Dia.
On reaching a suitable foundation material, a bulbous base is formed below the excavated depth, by expelling semi dry concrete with direct blows of a hammer of mass 600 kgs to 1500 kgs, depending on the dia of the Pile. Consolidation of the base is sufficient.
This is followed by introducing the needed reinforcing cage and the shaft is formed by successive charges of Concrete, mixed in the proportion by volume of 1 part cement, 2 ½ parts sand, 3 ½ parts aggregate (20mm) being discharged and consolidated with the hammer, which works within the reinforcement cage, concurrent with the withdrawal of any temporary casing.
In soil conditions where difficulty is experienced in sealing off the ingress of water into the piling tube, special techniques are resorted to, so as it seal the tubes, depending on soil conditions.
We have seven Rigs of this type and various sizes of casing. Please see the photocopy of such rig at work.
In case of large diameter and where the scope of work is big, than we go for Rotary Augured Piles, in this case we need heavy plant such as crane, Watson, various sizes of Augers, Temporary Casing and Tools. Usage of such plant is not economical for a small Piling job, remote area and restricted working space.
Driven Piles
There are various types of driven piles, such as pre-cast concrete pile, H Steel pile, B.S.P cased Driven Cast insitu Piles.
Features of these piles are small displacement of materials during driving with the result that penetration of dense material the facility to extend piles by welding on site, in case of H sections and tube piles. While in case of pre-cast concrete piles, one needs much heavier crane, specially leveled casting and curing yard, specially lifting and loading and handling arrangement to avoid cracking.
Method
Pre-casted Concrete piles, H section Universal piles or open-ended or close-ended steel tubes, are top driven with either Drop Hammer or self-acting Diesel Hammer to suitable resistance. Successive lengths are butt welded in the field and driven, while in case of concrete piles special connections are pre casted in concrete.
On reaching the required depth or suitable driving resistance the piles are cut to the required cut-off level and in corporate into concrete cap.
Such piles are driven using a piling leader to suit the selected Hammer.
We have the needed Plant and carnage as well as various hammers.
Labor Intensive application
The firm has experienced in applying Labor Intensive Method of work in Construction. The company personnel have applied this method on some of our completed projects.
For Example
In 1992 motorable access road was made to lower Kihansi Falls Site, near Morogoro Tanzania with a labor force of over 600 persons. In six weeks 15 km . of road, through a steep forested area was made ready in order to move our machines. This included 112 Nos. of Temporary Bridge made by cutting big trees.
Similarly an approach access road for our Low Loader carrying 40 Tons Crawler Crane from Malindi to Baricho Wellfield Site was made by Labor Force. This included access to move our heavy machines between the Wellfield area.