【Daily Discussion】Utilities - Civil Engineering - 20210504

1. Conversion of concrete mixing ratios: The mixing ratios determined in the laboratory should have no oversized particles in any of the aggregate fractions, and the aggregates should be in a saturated surface-dry state. However, during construction, various grades of aggregates often contain a certain amount of undersized particles, and their water content is usually above the saturated surface-dry state. Therefore, the laboratory mix ratio should be converted into a field mix ratio based on the measured content of oversized aggregates and the surface moisture content of sand and gravel. Its purpose is to accurately achieve the laboratory mix ratio, rather than changing it. Adjustment amount = (Sum of the excess and deficiency amounts for that grade) – (Excess amount of the next lower grade + Deficiency amount of the previous grade). 2. Adjustment of concrete mix proportions: The concrete mix proportions determined in the laboratory may not always be suitable for actual construction conditions; moreover, when there are changes in construction equipment, transportation methods, distance of transport, or construction climate, the required slump value of the concrete also changes. To ensure that the workability of the concrete meets the construction requirements, it is necessary to make appropriate adjustments to the concrete’s moisture content and water usage (while keeping the water-cement ratio constant). 3. The concrete mix proportion must meet the requirements regarding engineering technical performance and construction techniques, so as to ensure smooth concrete construction and that the concrete attains the required strength and other properties as specified in the project.

1. Conversion of concrete mixing ratios: The mixing ratios determined in the laboratory should have no oversized particles in any of the aggregate fractions, and the aggregates should be in a saturated surface-dry state. However, during construction, various grades of aggregates often contain a certain amount of undersized particles, and their water content is usually above the saturated surface-dry state. Therefore, the laboratory mix ratio should be converted into a field mix ratio based on the measured content of oversized aggregates and the surface moisture content of sand and gravel. Its purpose is to accurately achieve the laboratory mix ratio, rather than changing it. Adjustment amount = (Sum of the excess and deficiency amounts for that grade) – (Excess amount of the next lower grade + Deficiency amount of the previous grade). 2. Adjustment of concrete mix proportions: The concrete mix proportions determined in the laboratory may not always be suitable for actual construction conditions; moreover, when there are changes in construction equipment, transportation methods, distance of transport, or construction climate, the required slump value of the concrete also changes. To ensure that the workability of the concrete meets the construction requirements, it is necessary to make appropriate adjustments to the concrete’s moisture content and water usage (while keeping the water-cement ratio constant). 3. The concrete mix proportion must meet the requirements regarding engineering technical performance and construction techniques, so as to ensure smooth concrete construction and that the concrete attains the required strength and other properties as specified in the project.

1. Conversion of concrete mixing ratios: The mixing ratios determined in the laboratory should have no oversized particles in any of the aggregate fractions, and the aggregates should be in a saturated surface-dry state. However, during construction, various grades of aggregates often contain a certain amount of undersized particles, and their water content is usually above the saturated surface-dry state. Therefore, the laboratory mix ratio should be converted into a field mix ratio based on the measured content of oversized aggregates and the surface moisture content of sand and gravel. Its purpose is to accurately achieve the laboratory mix ratio, rather than changing it. Adjustment amount = (Sum of the excess and deficiency amounts for that grade) – (Excess amount of the next lower grade + Deficiency amount of the previous grade). 2. Adjustment of concrete mix proportions: The concrete mix proportions determined in the laboratory may not always be suitable for actual construction conditions; moreover, when there are changes in construction equipment, transportation methods, distance of transport, or construction climate, the required slump value of the concrete also changes. To ensure that the workability of the concrete meets the construction requirements, it is necessary to make appropriate adjustments to the concrete’s moisture content and water usage (while keeping the water-cement ratio constant). 3. The concrete mix proportion must meet the requirements regarding engineering technical performance and construction techniques, so as to ensure smooth concrete construction and that the concrete attains the required strength and other properties as specified in the project.

1. Conversion of concrete mixing ratios: The mixing ratios determined in the laboratory should have no oversized particles in any of the aggregate fractions, and the aggregates should be in a saturated surface-dry state. However, during construction, various grades of aggregates often contain a certain amount of undersized particles, and their water content is usually above the saturated surface-dry state. Therefore, the laboratory mix ratio should be converted into a field mix ratio based on the measured content of oversized aggregates and the surface moisture content of sand and gravel. Its purpose is to accurately achieve the laboratory mix ratio, rather than changing it. Adjustment amount = (Sum of the excess and deficiency amounts for that grade) – (Excess amount of the next lower grade + Deficiency amount of the previous grade). 2. Adjustment of concrete mix proportions: The concrete mix proportions determined in the laboratory may not always be suitable for actual construction conditions; moreover, when there are changes in construction equipment, transportation methods, distance of transport, or construction climate, the required slump value of the concrete also changes. To ensure that the workability of the concrete meets the construction requirements, it is necessary to make appropriate adjustments to the concrete’s moisture content and water usage (while keeping the water-cement ratio constant). 3. The concrete mix proportion must meet the requirements regarding engineering technical performance and construction techniques, so as to ensure smooth concrete construction and that the concrete attains the required strength and other properties as specified in the project.

1. Conversion of concrete mixing ratios: The mixing ratios determined in the laboratory should have no oversized particles in any of the aggregate fractions, and the aggregates should be in a saturated surface-dry state. However, during construction, various grades of aggregates often contain a certain amount of undersized particles, and their water content is usually above the saturated surface-dry state. Therefore, the laboratory mix ratio should be converted into a field mix ratio based on the measured content of oversized aggregates and the surface moisture content of sand and gravel. Its purpose is to accurately achieve the laboratory mix ratio, rather than changing it. Adjustment amount = (Sum of the excess and deficiency amounts for that grade) – (Excess amount of the next lower grade + Deficiency amount of the previous grade). 2. Adjustment of concrete mix proportions: The concrete mix proportions determined in the laboratory may not always be suitable for actual construction conditions; moreover, when there are changes in construction equipment, transportation methods, distance of transport, or construction climate, the required slump value of the concrete also changes. To ensure that the workability of the concrete meets the construction requirements, it is necessary to make appropriate adjustments to the concrete’s moisture content and water usage (while keeping the water-cement ratio constant). 3. The concrete mix proportion must meet the requirements regarding engineering technical performance and construction techniques, so as to ensure smooth concrete construction and that the concrete attains the required strength and other properties as specified in the project.

1. Conversion of concrete mixing ratios: The mixing ratios determined in the laboratory should have no oversized particles in any of the aggregate fractions, and the aggregates should be in a saturated surface-dry state. However, during construction, various grades of aggregates often contain a certain amount of undersized particles, and their water content is usually above the saturated surface-dry state. Therefore, the laboratory mix ratio should be converted into a field mix ratio based on the measured content of oversized aggregates and the surface moisture content of sand and gravel. Its purpose is to accurately achieve the laboratory mix ratio, rather than changing it. Adjustment amount = (Sum of the excess and deficiency amounts for that grade) – (Excess amount of the next lower grade + Deficiency amount of the previous grade). 2. Adjustment of concrete mix proportions: The concrete mix proportions determined in the laboratory may not always be suitable for actual construction conditions; moreover, when there are changes in construction equipment, transportation methods, distance of transport, or construction climate, the required slump value of the concrete also changes. To ensure that the workability of the concrete meets the construction requirements, it is necessary to make appropriate adjustments to the concrete’s moisture content and water usage (while keeping the water-cement ratio constant). 3. The concrete mix proportion must meet the requirements regarding engineering technical performance and construction techniques, so as to ensure smooth concrete construction and that the concrete attains the required strength and other properties as specified in the project.

1. Conversion of concrete mixing ratios: The mixing ratios determined in the laboratory should have no oversized particles in any of the aggregate fractions, and the aggregates should be in a saturated surface-dry state. However, during construction, various grades of aggregates often contain a certain amount of undersized particles, and their water content is usually above the saturated surface-dry state. Therefore, the laboratory mix ratio should be converted into a field mix ratio based on the measured content of oversized aggregates and the surface moisture content of sand and gravel. Its purpose is to accurately achieve the laboratory mix ratio, rather than changing it. Adjustment amount = (Sum of the excess and deficiency amounts for that grade) – (Excess amount of the next lower grade + Deficiency amount of the previous grade). 2. Adjustment of concrete mix proportions: The concrete mix proportions determined in the laboratory may not always be suitable for actual construction conditions; moreover, when there are changes in construction equipment, transportation methods, distance of transport, or construction climate, the required slump value of the concrete also changes. To ensure that the workability of the concrete meets the construction requirements, it is necessary to make appropriate adjustments to the concrete’s moisture content and water usage (while keeping the water-cement ratio constant). 3. The concrete mix proportion must meet the requirements regarding engineering technical performance and construction techniques, so as to ensure smooth concrete construction and that the concrete attains the required strength and other properties as specified in the project.

1. Conversion of concrete mixing ratios: The mixing ratios determined in the laboratory should have no oversized particles in any of the aggregate fractions, and the aggregates should be in a saturated surface-dry state. However, during construction, various grades of aggregates often contain a certain amount of undersized particles, and their water content is usually above the saturated surface-dry state. Therefore, the laboratory mix ratio should be converted into a field mix ratio based on the measured content of oversized aggregates and the surface moisture content of sand and gravel. Its purpose is to accurately achieve the laboratory mix ratio, rather than changing it. Adjustment amount = (Sum of the excess and deficiency amounts for that grade) – (Excess amount of the next lower grade + Deficiency amount of the previous grade). 2. Adjustment of concrete mix proportions: The concrete mix proportions determined in the laboratory may not always be suitable for actual construction conditions; moreover, when there are changes in construction equipment, transportation methods, distance of transport, or construction climate, the required slump value of the concrete also changes. To ensure that the workability of the concrete meets the construction requirements, it is necessary to make appropriate adjustments to the concrete’s moisture content and water usage (while keeping the water-cement ratio constant). 3. The concrete mix proportion must meet the requirements regarding engineering technical performance and construction techniques, so as to ensure smooth concrete construction and that the concrete attains the required strength and other properties as specified in the project.

1. Conversion of concrete mixing ratios: The mixing ratios determined in the laboratory should have no oversized particles in any of the aggregate fractions, and the aggregates should be in a saturated surface-dry state. However, during construction, various grades of aggregates often contain a certain amount of undersized particles, and their water content is usually above the saturated surface-dry state. Therefore, the laboratory mix ratio should be converted into a field mix ratio based on the measured content of oversized aggregates and the surface moisture content of sand and gravel. Its purpose is to accurately achieve the laboratory mix ratio, rather than changing it. Adjustment amount = (Sum of the excess and deficiency amounts for that grade) – (Excess amount of the next lower grade + Deficiency amount of the previous grade). 2. Adjustment of concrete mix proportions: The concrete mix proportions determined in the laboratory may not always be suitable for actual construction conditions; moreover, when there are changes in construction equipment, transportation methods, distance of transport, or construction climate, the required slump value of the concrete also changes. To ensure that the workability of the concrete meets the construction requirements, it is necessary to make appropriate adjustments to the concrete’s moisture content and water usage (while keeping the water-cement ratio constant). 3. The concrete mix proportion must meet the requirements regarding engineering technical performance and construction techniques, so as to ensure smooth concrete construction and that the concrete attains the required strength and other properties as specified in the project.

1. Conversion of concrete mixing ratios: The mixing ratios determined in the laboratory should have no oversized particles in any of the aggregate fractions, and the aggregates should be in a saturated surface-dry state. However, during construction, various grades of aggregates often contain a certain amount of undersized particles, and their water content is usually above the saturated surface-dry state. Therefore, the laboratory mix ratio should be converted into a field mix ratio based on the measured content of oversized aggregates and the surface moisture content of sand and gravel. Its purpose is to accurately achieve the laboratory mix ratio, rather than changing it. Adjustment amount = (Sum of the excess and deficiency amounts for that grade) – (Excess amount of the next lower grade + Deficiency amount of the previous grade). 2. Adjustment of concrete mix proportions: The concrete mix proportions determined in the laboratory may not always be suitable for actual construction conditions; moreover, when there are changes in construction equipment, transportation methods, distance of transport, or construction climate, the required slump value of the concrete also changes. To ensure that the workability of the concrete meets the construction requirements, it is necessary to make appropriate adjustments to the concrete’s moisture content and water usage (while keeping the water-cement ratio constant). 3. The concrete mix proportion must meet the requirements regarding engineering technical performance and construction techniques, so as to ensure smooth concrete construction and that the concrete attains the required strength and other properties as specified in the project.