feat(result-contract-completion): step 0 — beam-element-end-recovery

2026-08-02 01:14:40 +09:00
parent 5618636f0d
commit 5fe57cb145
7 changed files with 341 additions and 11 deletions
@@ -22,6 +22,7 @@ constexpr double kShearAreaZ = 0.2;
 fesa::Beam3D2Input make_x_axis_input(const double length) {
    return {
        {{{0.0, 0.0, 0.0}, {length, 0.0, 0.0}}},
+        {fesa::NodeId{1}, fesa::NodeId{2}},
        {fesa::MaterialId{1}, "elastic", kYoung, kPoisson},
        {
            fesa::SectionId{1},
@@ -369,4 +370,191 @@ TEST(Beam3D2, PreservesGlobalEnergyUnderRigidCoordinateRotation) {
        4096.0 * std::numeric_limits<double>::epsilon());
 }

+TEST(BeamRecovery, RecoversPureAxialStrainAndForceAtBothEnds) {
+    fesa::Beam3D2Input input = make_x_axis_input(2.0);
+    input.node_ids = {fesa::NodeId{101}, fesa::NodeId{202}};
+    std::array<double, 12> displacement{};
+    displacement[6] = 0.4;
+
+    const auto results = fesa::recover_beam3d2(input, displacement, {});
+
+    ASSERT_EQ(results.size(), 2U);
+    EXPECT_DOUBLE_EQ(results[0].xi, -1.0);
+    EXPECT_EQ(results[0].end_node, fesa::NodeId{101});
+    EXPECT_DOUBLE_EQ(results[1].xi, 1.0);
+    EXPECT_EQ(results[1].end_node, fesa::NodeId{202});
+    for (const auto& result : results) {
+        expect_relative_near(result.section_strain[0], 0.2);
+        expect_relative_near(result.section_force[0], 16.8);
+        expect_relative_near(result.centroid_sigma_xx, 42.0);
+        for (std::size_t component = 1; component < 6; ++component) {
+            expect_relative_near(result.section_strain[component], 0.0);
+            expect_relative_near(result.section_force[component], 0.0);
+        }
+        EXPECT_TRUE(result.sigma_xx.empty());
+    }
+}
+
+TEST(BeamRecovery, RecoversPureTorsionAtBothEnds) {
+    fesa::Beam3D2Input input = make_x_axis_input(2.0);
+    input.node_ids = {fesa::NodeId{101}, fesa::NodeId{202}};
+    std::array<double, 12> displacement{};
+    displacement[9] = 0.6;
+    const double shear_modulus = kYoung / (2.0 * (1.0 + kPoisson));
+
+    const auto results = fesa::recover_beam3d2(input, displacement, {});
+
+    ASSERT_EQ(results.size(), 2U);
+    for (const auto& result : results) {
+        expect_relative_near(result.section_strain[3], 0.3);
+        expect_relative_near(
+            result.section_force[3],
+            shear_modulus * kTorsionJ * 0.3);
+        for (const std::size_t component :
+             std::array<std::size_t, 5>{0, 1, 2, 4, 5}) {
+            expect_relative_near(result.section_strain[component], 0.0);
+            expect_relative_near(result.section_force[component], 0.0);
+        }
+    }
+}
+
+TEST(BeamRecovery, UsesReducedIntegrationPointForShearAtBothEnds) {
+    fesa::Beam3D2Input input = make_x_axis_input(2.0);
+    std::array<double, 12> displacement{};
+    displacement[7] = 1.2;
+    displacement[5] = 0.2;
+    displacement[11] = 0.6;
+    displacement[8] = -0.4;
+    displacement[4] = 0.1;
+    displacement[10] = 0.5;
+    const double shear_modulus = kYoung / (2.0 * (1.0 + kPoisson));
+
+    const auto results = fesa::recover_beam3d2(input, displacement, {});
+
+    ASSERT_EQ(results.size(), 2U);
+    for (const auto& result : results) {
+        expect_relative_near(result.section_strain[1], 0.2);
+        expect_relative_near(result.section_strain[2], 0.1);
+        expect_relative_near(
+            result.section_force[1],
+            shear_modulus * kShearAreaY * 0.2);
+        expect_relative_near(
+            result.section_force[2],
+            shear_modulus * kShearAreaZ * 0.1);
+    }
+}
+
+TEST(BeamRecovery, UsesBeamFrameForGlobalDisplacements) {
+    fesa::Beam3D2Input input = make_x_axis_input(2.0);
+    input.coordinates = {{{0.0, 0.0, 0.0}, {0.0, 2.0, 0.0}}};
+    input.section.orientation = {0.0, 0.0, 1.0};
+    input.node_ids = {fesa::NodeId{101}, fesa::NodeId{202}};
+    std::array<double, 12> displacement{};
+    displacement[7] = 0.4;
+    displacement[10] = 0.6;
+    const double shear_modulus = kYoung / (2.0 * (1.0 + kPoisson));
+
+    const auto results = fesa::recover_beam3d2(input, displacement, {});
+
+    ASSERT_EQ(results.size(), 2U);
+    for (const auto& result : results) {
+        expect_relative_near(result.section_strain[0], 0.2);
+        expect_relative_near(result.section_force[0], 16.8);
+        expect_relative_near(result.section_strain[3], 0.3);
+        expect_relative_near(
+            result.section_force[3],
+            shear_modulus * kTorsionJ * 0.3);
+    }
+}
+
+TEST(SectionForce, RecoversPureBendingAboutLocalYAtBothEnds) {
+    fesa::Beam3D2Input input = make_x_axis_input(2.0);
+    input.node_ids = {fesa::NodeId{101}, fesa::NodeId{202}};
+    std::array<double, 12> displacement{};
+    displacement[4] = -0.4;
+    displacement[10] = 0.4;
+
+    const auto results = fesa::recover_beam3d2(input, displacement, {});
+
+    ASSERT_EQ(results.size(), 2U);
+    for (const auto& result : results) {
+        expect_relative_near(result.section_strain[4], 0.4);
+        expect_relative_near(result.section_force[4], 2.52);
+        for (const std::size_t component :
+             std::array<std::size_t, 5>{0, 1, 2, 3, 5}) {
+            expect_relative_near(result.section_strain[component], 0.0);
+            expect_relative_near(result.section_force[component], 0.0);
+        }
+    }
+}
+
+TEST(SectionForce, RecoversPureBendingAboutLocalZAtBothEnds) {
+    fesa::Beam3D2Input input = make_x_axis_input(2.0);
+    input.node_ids = {fesa::NodeId{101}, fesa::NodeId{202}};
+    std::array<double, 12> displacement{};
+    displacement[5] = 0.25;
+    displacement[11] = -0.25;
+
+    const auto results = fesa::recover_beam3d2(input, displacement, {});
+
+    ASSERT_EQ(results.size(), 2U);
+    for (const auto& result : results) {
+        expect_relative_near(result.section_strain[5], -0.25);
+        expect_relative_near(result.section_force[5], -2.625);
+        for (const std::size_t component :
+             std::array<std::size_t, 5>{0, 1, 2, 3, 4}) {
+            expect_relative_near(result.section_strain[component], 0.0);
+            expect_relative_near(result.section_force[component], 0.0);
+        }
+    }
+}
+
+TEST(SectionForce, PreservesBiaxialBendingSignsAtBothEnds) {
+    fesa::Beam3D2Input input = make_x_axis_input(2.0);
+    input.node_ids = {fesa::NodeId{101}, fesa::NodeId{202}};
+    std::array<double, 12> displacement{};
+    displacement[4] = -0.4;
+    displacement[10] = 0.4;
+    displacement[5] = 0.25;
+    displacement[11] = -0.25;
+
+    const auto results = fesa::recover_beam3d2(input, displacement, {});
+
+    ASSERT_EQ(results.size(), 2U);
+    for (const auto& result : results) {
+        expect_relative_near(result.section_force[4], 2.52);
+        expect_relative_near(result.section_force[5], -2.625);
+    }
+}
+
+TEST(CentroidStress, UsesAxialStressAndPreservesRecoveryPointOrder) {
+    fesa::Beam3D2Input input = make_x_axis_input(2.0);
+    input.node_ids = {fesa::NodeId{101}, fesa::NodeId{202}};
+    std::array<double, 12> displacement{};
+    displacement[6] = 0.2;
+    displacement[4] = -0.2;
+    displacement[10] = 0.2;
+    displacement[5] = 0.3;
+    displacement[11] = -0.3;
+    const std::array<std::array<double, 2>, 3> recovery_points{{
+        {2.0, 3.0},
+        {-1.0, 4.0},
+        {5.0, -2.0},
+    }};
+
+    const auto results = fesa::recover_beam3d2(
+        input,
+        displacement,
+        recovery_points);
+
+    ASSERT_EQ(results.size(), 2U);
+    for (const auto& result : results) {
+        expect_relative_near(result.centroid_sigma_xx, 21.0);
+        ASSERT_EQ(result.sigma_xx.size(), recovery_points.size());
+        expect_relative_near(result.sigma_xx[0], 273.0);
+        expect_relative_near(result.sigma_xx[1], 126.0);
+        expect_relative_near(result.sigma_xx[2], 252.0);
+    }
+}
+
 }  // namespace