Foundation Construction

Introduction to foundation construction of electronic truck scales

As a common large electronic weighing equipment product, electronic truck scales have various different installation and usage modes, can choose a foundation-pit-free ground scale installation mode and a shallow foundation pit platform scale installation mode, and are suitable for occasions with different weighing requirements. Our company provides design drawings for users according to user requirements. Users can design construction drawings in combination with field geological conditions according to the provided basic design drawings.

Basic construction process and precautions of electronic truck scales

1. Engineering construction order of electronic loadometer:

Setting out→checking→excavation of foundation trenches→trench cleaning→fill exchanging, macadam grinding→C15 concrete bedding→L1.L2.L3 and bottom plate steel bar binding→form bracing→concrete pouring

2. Measurement and setting out:

Elevation: ±0.00 is equivalent to the absolute elevation 34.50m.

Axis net: be led in from J1.J2 point.

3. Trench cleaning

Stop mechanical excavation until more than 100m higher than the designed elevation has been reached, and then take hand excavation.

Clean up the base tank, elevation requirements to meet the design requirements of the standard, the error control in the specification of the range of +30-50MM.

4. Fill exchanging:

Remove mixed backfill soil and cultivation soil under foundation within the range of 1,700mm under basement; adopt 1,300mm macadam and 750mmC15 concrete bedding, and roll macadam by a 18T road roller. Carry out layered pavement and layered compaction, with 200mm-300mm pavement on each layer.

5. Concrete bedding:

Processes: foundation trench cleaning→form bracing at the periphery of the bedding, and watering to wet the trench bottom→approach checking of concrete→concrete pouring, vibration, floating→concrete curing

6. L1.L2.L3 and steel bar binding

6. Mark off the position line of steel bars: work out the number of steel bars actually needed by bottom plates according to the steel bar distance indicated by drawings; generally, the steel bar close to the template edge of the bottom plate is 5cm away from the edge of the template, and eject the position line of steel bars on the bottom plate.

Foundation construction and foundation bottom plate steel bars of electronic truck scales:

1. Pave steel bars according to the ejected position line of steel bars. Bind steel bars according to drawings.

2. Every cross point on two rows close to the periphery should be bound in the process of binding steel bars. Cross points in the middle can be bound at a distance in a staggered way; steel bars stressed in two directions must be totally bound at the cross points of steel bars.

3. Arrange mortar cushion blocks for bottom plate concrete protection layers: the thickness of cushion blocks is equal to that of protection layers; carry out plum blossom type arrangement at intervals of about 1m.

4. When double-layer steel bars are applied to foundation bottom plates, arrange the steel bar bracket after steel bars on the lower layer are bound, and arrange a horizontal positioning steel bar and a longitudinal positioning steel bar on the steel bar bracket; the upper/lower order and binding method of steel bars are the same as those of steel bars on the lower layer of the bottom plate.

5. The positions of straight screwed joints of steel bars should also accord with the stipulations of construction specifications.

6. The positions of steel bar joints on upper and lower layers of the foundation bottom plate should meet the design requirements.

Other problems needing attention in foundation construction of electronic truck scales

1. The plain soil bearing capacity (earth bearing capacity) under foundation is required to be not less than 20t/m2. Reinforcement treatment is essential if field geological conditions cannot meet this requirement.

2. Do excavate to the line below the local frozen soil line during foundation excavation.

3. A drainage channel must be designed for shallow foundation pit basis. Surrounding drainage problems should also be taken into consideration without foundation pit basis, to ensure that truck scales cannot be submerged into water in rain.

4. Longitudinal and horizontal steel bar nets in foundation concrete should be bound at over 50% cross points by 16# iron wires, and be connected to all the iron bottom plates by steel bars (to be used as ground wires of weighing sensors).

5. Embedded parts (iron bottom plates, foundation bolts, angle iron safe edges, etc.) in foundation construction should be prepared by users. Measures must be taken in construction, to ensure correct positions of foundation bolts and iron bottom plates. Therefore, a secondary grouting method is suggested to be used for positioning, to ensure that cavities must not be formed between iron bottom plates and concrete. The levelness and elevation of all the iron bottom plates in construction must be ensured to meet the requirements of basic design drawings. The equation of equal altitude in the centers of all the iron bottom plates should be less than 2mm, the horizontal inclination of iron bottom plates should be less than 1/500, and the diagonal deviation of the center distances of all the iron bottom plates should be less than 2mm.

6. Do pay attention to maintenance after the completion of foundation construction. Weighing platforms are forbidden to be mounted if concrete does not reach the design strength. “Early strength agent” and other measures are allowed to be added into concrete during construction, to shorten the construction period and maintenance time.

Importance of foundation construction of electronic truck scales

Electronic truck scales are taken as main measurement means for automobile load weighing; with rapid development of automobile technologies and automobile industry, increasing enlargement of vehicle models as well as constant increase of deadweight tonnage, the measurement accuracy and measurement stability of truck scales are one of important subjects in front of every measurement workers. However, the basic part construction of truck scales seams especially important, that is to say, the only way of best ensuring the measurement accuracy and stability of electronic truck scales is well construction of basic parts.